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THES‘S IIIIIIIIIIIIIIIIIIIIIIIIIIIII

31293 01710 2868

This is to certify that the

thesis entitled

THE USE OF PREHARVEST INTERVALS, POSTHARVEST WASH
TREATMENTS, AND PROCESSING IN THE REMOVAL OF
PESTICIDES FROM APPLE FRUIT,

presented by

MATTHEW DELL SILER

has been accepted towards fulfillment
of the requirements for

M.S. degreeinFOOD SCIENCE

 

Q/7 MCW/

/ /Majorroessopf

[hue MAY 08; 1998

0-7639 MS U is an Affirmative Action/Equal Opportunity Institution

 

 

 

 

 

LIBRARY

Mlchlgan State
Unlverslty

 

 

 

PLACE IN RETURN BOX
to remove this checkout from your record.
To AVOID FINES return on or before date due.

 

DATE DUE DATE DUE DATE DUE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

mo mus-am

 

THE USE OF PREHARVESTS INTERVALS, POSTHARVEST
WASH TREATMENTS, AND PROCESSING IN THE
REMOVAL OF PESTICIDES FROM APPLE FRUIT

By

Matthew Dell Siler

A THESIS
Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of
MASTERS OF SCENCE
Department of Food Science & Human Nutrition

1998

ABSTRACT

THE USE F0 PREHARVEST INTERVALS, POSTHARVEST WASH
TREATMENTS, AND PROCESSING IN THE
REMOVAL OF PESTICIDES FROM APPLE FRUIT
By

Matthew Dell Siler

The objective of this study was to determine the effectiveness of preharvest intervals
(PHI), postharvest wash treatments, and processing on pesticide residues in raw and
processed apple fruits.

Field studies conducted over a three year period, sprayed Golden Delicious apples with
label rates of the pesticides captan and azinphosmethyl Spray treatments were altered to
study the effects of PHI on residue levels. Treated apples were subjected to Six different
postharvest wash treatments: (1) 21° C and pH 7; (2) 21° C and pH 11; (3) 43° C and
pH 7; (4) 43° C and pH 11; (5) 21° C and pH 7, 500 ug/g Chlorine; (6) 21° C and pH 7,
2% Sodium Dodecyl Sulfate (SDS). This was followed by processing into four difl‘erent
products (peeled and unpeeled applesauce, juice, and slices).

The following postharvest wash variables were found most effective in the removal of
the two pesticides: pH 11, 43° C, chlorine, SDS, and a longer wash time. The
combination of postharvest wash treatments and processing resulted in high reductions of

both pesticides for all products.

DEDICATED TO
My parents, Lorraine and Dell Siler, and my Grandmother, Mrs. Ethelyn Siler,

for thier love, support and guidance through the years

ACKNOWLEDGENIENTS

I wish to express my sincere gratitude to all those people who have in one way or
another contributed to the successful completion of my Masters program I would truely
like to thank my Major Professor, Dr. Jerry N. Cash, for his support, guidance, and
confidence in me throughout the entire program. To Dr. Gale Strasburg for being on my
committee, reviewing this manuscript and providing his guidance. To Dr. Matthew J.
Zabik for serving on my committee and providing support, guidance, and his technical
expertise which has proven invaluable.

I would like to thank my co-worker, Chris Vandervoort, for her advice, support, and
fiiendship through the completion of my thesis (paper). To Glenn Dickmann for his
advice and technical assistance. To co-workers in Dr. Jerry N. Cash’s laboratory for
helping with three years of sample processing.

Acknowledgement is made to the Michigan Agricultural Experiment Station, Gerber
Products Company, Miles Inc., and the Michigan Apple Industry for their support for this
research.

I want to give special thanks to my parents, my sister Marti, my brother Lee and his
family, and my Grandmother Siler for their love, support, and belief in my abilities. To
Rayan Ray for her help and support. Oh ya, thanks to John “Emmer” Hayden, we’ll see

you the next time your up.

TABLE OF CONTENTS

Page
LIST OF TABLES ..................................................................................................... viii
LIST OF FIGURES ...................................................................................................... ix
LIST OF APPENDICES ............................................................................................ xiv
INTRODUCTION ......................................................................................................... 1
LITERATURE REVIEW .............................................................................................. 4
A. Pesticide Use and Monitoring ............................................................................ 4
B. Pesticides Involved ............................................................................................ 8
1. Azinphosmethyl .......................................................................................... 8
2. Captan ........................................................................................................ 9
C. Pesticide Residues in Raw Fruits and Vegetables ............................................ 10
D. Pesticide Residues in Processed Fruits and Vegetables ................................... 15
B. Common Pathways of Pesticide Residue Degradation ..................................... 17
1. Physical .................................................................................................... 18
2. Chemical ................................................................................................... 20
F. Effect of Processing on the Degradation and Removal of
Pesticide Residues .......................................................................................... 22
1. Temperature ............................................................................................. 23
2. Detergents ................................................................................................ 24
3. pH ............................................................................................................ 25
4. Chlorine .................................................................................................... 26
MATERIALS AND METHODS ................................................................................. 28
A. Orchard Study ................................................................................................. 28
l. Orchard Applications ................................................................................ 28
2. Sampling and Harvesting .......................................................................... 32
3. Fruit Post Harvest Treatments .................................................................. 32
a. Post Harvest Wash Preparation .......................................................... 33
b. Post Harvest Wash Treatment ............................................................ 34
4. Fruit Processing ........................................................................................ 35
a. Apple Slices ....................................................................................... 35
b. Apple Juice, 1993 Method ................................................................. 35

c. Apple Juice, 1993 and 1994 Method .................................................. 36

d. Applesauce, Peeled and Unpeeled ...................................................... 36

B. Sample Extraction and Cleanup ....................................................................... 36
1. Reagents ................................................................................................... 36

2. Chemicals ................................................................................................. 37

3. Glassware ................................................................................................. 37

4. Extraction and Cleanup ............................................................................. 37

5. Gas Chromatographic Analysis ................................................................. 38

a. Azinphosmethyl ................................................................................. 38

b. Captan ............................................................................................... 39

6. Calculation of Pesticide Residue Concentration ......................................... 39

7. Method Recovery Study ........................................................................... 40

8. Method Detection Limit Study .................................................................. 4O

9. Statistical Analysis .................................................................................... 40
RESULTS AND DISCUSSION .................................................................................. 41
A. Chromatographic Analysis ............................................................................... 41
1. Azinphosmethyl ........................................................................................ 41

2. Captan ....................................................................................................... 44

B. Pesticide Residues in Unprocessed Apples ...................................................... 47
1. Preharvest Interval Study .......................................................................... 47

2. Residue Levels in Raw Apples .................................................................. 53

3. Product Yield ........................................................................................... 54

C. Azinphosmethyl Residue Study ...................................................................... 56
l. Postharvest Wash Treatment Variables ..................................................... 56

a. Effect of Postharvest Wash pH at 21°C .............................................. 56

b. Effect of Postharvest Wash pH at 43°C .............................................. 61

c. Effect of Postharvest Wash Temperature at pH 7 ............................... 66

d. Effect of Postharvest Wash Temperature at pH 11 ............................. 71

e. Efl‘ect of 500 ug/g Chlorine in Postharvest Wash ................................ 76

f. Effect of 2% Sodium Dodecyl Sulfate in Postharvest Wash ................. 81

2. Comparison of Postharvest Wash Treatments ............................................ 87

3. Comparison of Raw Apple and Processed Apple Residues ...................... 100

4. Comparison of Residue Levels between Products .................................... 104

D. Captan Residue Study .................................................................................. 106
1 Postharvest Wash Treatment Variables ................................................... 107

a. Effect of Postharvest Wash pH at 21°C ............................................ 107

b. Effect of Postharvest Wash pH at 43°C ............................................ 110

c. Effect of Postharvest Wash Temperature at pH 7 ............................. 113

(1. Effect of Postharvest Wash Temperature at pH 11 ........................... 113

e. Effect of 500 ug/g Chlorine in Postharvest Wash .............................. 118

f. Effect of 2% Sodium Dodecyl Sulfate in Postharvest Wash ............... 118

2. Comparison of Postharvest Wash Treatments .......................................... 124

3. Comparison of Raw Apple and Processed Apple Residues ...................... 124

4. Comparison of Residue Levels between Products .................................... 134

SUWARY AND CONCLUSION ........................................................................... 136

FUTURE WORK ...................................................................................................... 140
APPENDICES .......................................................................................................... 14 l
BIBLIOGRAPHY ..................................................................................................... 160

vii

*Ffl'ii

Table 1.

Table 2.

Table 3.

Table 4.

Table 5.

Table 6.

Table 7.

Table 8.

Table 9.

LIST OF TABLES

1993 Spray Schedule for Golden Delicious Apples Fag;
1994 Spray Schedule for Golden Delicious Apples ........................................ 30
1995 Spray Schedule for Golden Delicious Apples ........................................ 31
Postharvest Wash Treatment Samples ........................................................... 34
Azinphosmethyl and Captan Recovery Study ................................................. 44
Azinphosmethyl and Captan Residues in Raw Apples .................................... 52
Yield Data for 1993-1995 .............................................................................. 55
Percent Reduction in Azinphosmethyl Residues Following Postharvest
Washing and Processing .............................................................................. 103
Percent Reduction in Captan Residues Following Postharvest

Washing and Processing ............................................................................... 133

viii

LIST OF FIGURES

Page

Figure 1. Structure of Azinphosmethyl .......................................................................... 8
Figure 2. Structure of Captan ..................................................................................... 10
Figure 3. GC Chromatogram of an Azinphosmethyl Standard ..................................... 42
Figure 4. GC Chromatogram of an Azinphosmethyl Sample ........................................ 43
Figure 5. GC Chromatogram of a Captan Standard ..................................................... 45
Figure 6. GC Chromatogram of a Captan Sample ........................................................ 46
Figure 7. Azinphosmethyl Residues in Raw Apple ....................................................... 49
Figure 8. Captan Residues in Raw Apple ..................................................................... 50
Figure 9. Effect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 21°C in Peeled Applesauce ....................................................................... 57
Figure 10. Effect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 21°C In Unpeeled Applesauce ................................................................. 58
Figure 11. Efi‘ect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 21°C in Apple Juice ................................................................................. 59
Figure 12. Effect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 21°C in Apple Slices ................................................................................ 60
Figure 13. Effect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 43°C in Peeled Applesauce ...................................................................... 62
Figure 14. Effect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 43°C in Unpeeled Applesauce ................................................................. - 63

ix

 

Figure 15.

Figure 16.

Figure 17.

Figure 18.

Figure 19.

Figure 20.

Figure 21.

Figure 22.

Figure 23.

Figure 24.

Figure 25.

Figure 26.

Figure 27.

Figure 28.

Figure 29.

Efl‘ect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 43°C in Apple Juice ................................................................................. 64
Efl‘ect of Postharvest Wash pH on the Removal of Azinphosmethyl

at 43°C in Apple Slices ................................................................................ 65
Effect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 7 in Peeled Applesauce ............................................ 67
Effect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 7 in Unpeeled Applesauce ........................................ 68
Efl‘ect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 7 in Apple Juice ....................................................... 69
Efiea of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 7 in Apple Slices ...................................................... 70
Efi‘ect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 11 in Peeled Applesauce .......................................... 72
Efl‘ect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 11 in Unpeeled Applesauce ...................................... 73
Effect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 11 in Apple Juice ..................................................... 74
Effect of Postharvest Wash Temperature on the Removal of

Azinphosmethyl at pH 11 in Apple Slices .................................................... 75
Effect of 500 ppm Chlorine on the Removal of Azinphosmethyl

at 21°C and pH 7 in Peeled Applesauce ....................................................... 77
Effect of 500 ppm Chlorine on the Removal of Azinphosmethyl

at 21°C and pH 7 in Unpeeled Applesauce .................................................. 78
Effect of 500 ppm Chlorine on the Removal of Azinphosmethyl

at 21°C and pH 7 in Apple Juice .................................................................. 79
Effect of 500 ppm Chlorine on the Removal of Azinphosmethyl

at 21°C and pH 7 in Apple Slices ................................................................ 80

Effect of 2% SDS on the Removal of Azinphosmethyl at 21°C
and pH 7 in Peeled Applesauce ................................................................... 82

 

Figure 30. Efi‘ect of 2% SDS on the Removal of Azinphosmethyl at 21°C
and pH 7 in Unpeeled Applesauce ................................................................ 83

Figure 31.Effect of 2% SDS on the Removal of Azinphosmethyl at 21°C
and pH 7 in Apple Juice ............................................................................... 84

Figure 32. Efi‘ect of 2% SDS on the Removal of Azinphosmethyl at 21°C
and pH 7 in Apple Slices .............................................................................. 85

Figure 33. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Peeled Applesauce, 1993 Data .................................................... 88

Figure 34. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Peeled Applesauce, 1994 Data .................................................... 89

Figure 35. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Peeled Applesauce, 1995 Data .................................................... 90

Figure 36. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Unpeeled Applesauce, 1993 Data ................................................ 91

Figure 37. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Unpeeled Applesauce, 1994 Data ................................................ 92

Figure 38. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Unpeeled Applesauce, 1995 Data ................................................ 93

Figure 39. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Apple Juice, 1993 Data ............................................................... 94

Figure 40. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Apple Juice, 1994 Data ............................................................... 95

Figure 41. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Apple Juice, 1995 Data ............................................................... 96

Figure 42. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Apple Slices, 1993 Data .............................................................. 97

Figure 43. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Apple Slices, 1994 Data .............................................................. 98

Figure 44. Comparison of Postharvest Wash Treatments - Azinphosmethyl
Residue in Apple Slices, 1995 Data99

 

 

Figure 45. Percent Reduction of Azinphosmethyl Residues in Peeled

Applesauce ................................................................................................ 101
Figure 46. Percent Reduction of Azinphosmethyl Residues in Unpeeled

Applesauce ................................................................................................ 101
Figure 47. Percent Reduction of Azinphosmethyl Residues in Apple Juice .................. 102
Figure 48. Percent Reduction of Azinphosmethyl Residues in Apple Slices ................. 102
Figure 49. Comparison of Azinphosmethyl Residues in Apple Products ...................... 105

Figure 50. Effect of Postharvest Wash pH on the Removal of Captan
at 21°C in Apple Juice ............................................................................... 108

Figure 51. Efl‘ect of Postharvest Wash pH on the Removal of Captan
at 21°C in Apple Slices ............................................................................... 109

Figure 52. Effect of Postharvest Wash pH on the Removal of Captan
at 43°C in Apple Juice ................................................................................ 111

Figure 53. Effect of Postharvest Wash pH on the Removal of Captan
at 43°C in Apple Slices ............................................................................... 112

Figure 54. Efl‘ect of Postharvest Wash Temperature on the Removal
of Captan at pH 7 in Apple Juice ................................................................ 114

Figure 55. Effect of Postharvest Wash Temperature on the Removal
of Captan at pH 7 in Apple Slices .............................................................. 115

Figure 56. Effect of Postharvest Wash Temperature on the Removal
of Captan at pH 11 in Apple Juice .............................................................. 116

Figure 57. Effect of Postharvest Wash Temperature on the Removal
of Captan at pH 11 in Apple Slices ............................................................. 117

Figure 58. Effect of 500 ppm Chlorine on the Removal of Captan
at 21°C and pH 7 in Apple Juice ................................................................. 119

Figure 59. Effect of 500 ppm Chlorine on the Removal of Captan
at 21°C and pH 7 in Apple Slices ............................................................... 120

Figure 60. Effect of 2% SDS on the Removal of Captan at 21°C .
and pH 7 in Apple Juice ............................................................................. 121

xii

 

Figure 61. Effect of 2% SDS on the Removal of Captan at 21°C

and pH 7 in Apple Slices ............................................................................ 122
Figure 62. Comparison of Postharvest Wash Treatments - Captan Residue

in Apple Juice, 1993 Data .......................................................................... 125
Figure 63. Comparison of Postharvest Wash Treatments - Captan Residue

in Apple Juice, 1994 Data .......................................................................... 126
Figure 64. Comparison of Postharvest Wash Treatments - Captan Residue

in Apple Juice, 1995 Data .......................................................................... 127
Figure 65. Comparison of Postharvest Wash Treatments - Captan Residue

in Apple Slices, 1993 Data ......................................................................... 128
Figure 66. Comparison of Postharvest Wash Treatments - Captan Residue

in Apple Slices, 1994 Data ......................................................................... 129
Figure 67. Comparison of Postharvest Wash Treatments - Captan Residue

in Apple Slices, 1995 Data ......................................................................... 130
Figure 68. Percent Reduction of Captan Residues in Apple Juice ................................ 131
Figure 69. Percent Reduction of Captan Residues in Apple Slices .............................. 131
Figure 70. Comparison of Captan Residues in Apple Products ................................... 135

xiii

 

LIST OF APPENDICES

Page
Appendix 1. Field Plot Diagram ................................................................................ 141
Appendix 2. A Typical Standard Curve for Azinphosmethyl Standards ...................... 142
Appendix 3. A Typical Standard Curve for Captan Standards .................................... 143
Appendix 4. Raw Data for Azinphosmethyl Residues in Peeled Applesauce ............... 144
Appendix 5. Raw Data for Azinphosmethyl Residues in Unpeeled Applesauce .......... 146
Appendix 6. Raw Data for Azinphosmethyl Residues in Apple Juice ......................... 148
Appendix 7. Raw Data for Azinphosmethyl Residues in Apple Slices ........................ 150
Appendix 8. Raw Data for Captan Residues in Peeled Applesauce ............................ 152
Appendix 9. Raw Data for Captan Residues in Unpeeled Applesauce ........................ 154
Appendix 10. Raw Data for Captan Residues in Apple Juice ...................................... 156
Appendix 11. Raw Data for Captan Residues in Apple Slices ..................................... 158

xiv

 

INTRODUCTION

Consumer demand for food with good sensory quality has continued to sustain the use
of pesticides and made them a key component of agricultural technology. Pesticide use
provides numerous benefits in terms of increased production and product quality but can
also be expected to result in residues in food (Lombardo, 1989). It is therefore necessary
to confirm that fiesh and processed fiuits and vegetables are fiee of excessive pesticide
residues.

Fruits and vegetables are often subjected to a number of different processing
operations to clean, eliminate waste, and to make the raw materials more palatable. While
these procedures may actually help reduce or remove pesticide residues, other processing
methods have been specifically designed for such purposes. Washing including rinsing is,
perhaps, the one unit operation common to the preparation of nearly all fiuits and
vegetables for processing (Geisman, 197 5). While washing is a common practice among
the processing industry, the specific methodologies used varies among processors.
Chemical and physical aspects of wash treatments (i. e. temperature, detergents, pH,
chlorine, wash time) are often manipulated to produce optimum results. Washing of the
fiuits and vegetables is most often followed by further physical manipulation of the items

into a desired product. Commonly encountered technigues include peeling, trimming, _

blanching, juicing, and slicing. The net influence of processing almost always results in
residue levels in processed foods well below tolerance for the raw product (Elkins, 1989).

Apple (Malus x domestica Borkh.) is considered to be a major agricultural product
with substantial economic value. In terms of annual tonnage produced, apples are the
third most important fiuit corp grown in the United States (Downing, 1989). Michigan is
one of the nation’s most important apple producing states, with 9% of the total US.
production in 1987-1990 (Ricks and Hull, 1992). As a result of its high economic value as
well as the large number of plant diseases (apple scab, powdery mildew, and sooty
blotch), insects (codling moth, apple maggot, scales, and apple aphids), and mites (spider
mites) that infest apples during their growth, significant quantities of pesticides are often
necessary for the protection of this crop. This leads to residues on or in the fiuit at
harvest. Although these residue levels are generally below establishes tolerances,
consumer wariness warrants efforts to further reduce pesticide residues.

The two pesticides selected for this study were: Captan and Guthion®
(azinphosmethyl). The selection of these two pesticides was based on their importance in
the apple industry for control of major plant disease, insects, and mites. The pesticides
were also selected for their non-carcinogenic potential as indicated by the EPA.
Azinphosmethyl is a nonsystemic organophosphorus insecticide which works as a contact
or ingestion poison. Captan is a broad spectrum, non-systemic fungicide. Both pesticides
are widely used on both fruits, vegetables, and other field crops. Application of these
pesticides before harvest is often necessary for the proctection of fiuits during the

preharvest period.

The objective of the present study was to determine the efi‘ectiveness of preharvest
intervals (PHI), postharvest wash treatments, and processing on pesticide residues in raw

and processed apple fiuits.

LITERATURE REVIEW

A. Pesticide Use and Monitoring

The post-World War II introduction of synthetic organic chemicals such as DDT and 2,4-
D brought in a new era of farming that promised effective management of insects and
other destructive diseases and pests in a wide variety of crops (Lichtenberg and Zilberman,
1986). Since then, other chlorinated hydrocarbons along with newer, safer, and less
persistent pesticides have been developed. Such pesticides include the organophosphates,
carbamates, and the synthetic pyrethroids The total use of these pesticides in the US has
climbed dramatically, increasing fiom 250 million kilograms to 500 million kilograms
between 1964 and 1980. Of theses pesticides, those used for agricultural purposes more
than doubled, increasing from 150 million kilograms in 1964 to about 400 million
kilograms in 1980 (Aspelin and Ballard, 1980).

In the US, an estimated third of all crops is lost to pests prior to harvest, with an
additional 9% lost to pests after harvest (Pimental, 1976). The increased use of pesticides
has resulted in a significant reduction in crop loss due to insects and disease. The value of
harvest losses by pest, disease, and weeds is estimated worldwide to be about 35% of the
potential total harvest (Shrbamoto and Bjedanes, 1993 ). The consumers demand for food
with good sensory quality has continued to sustain the use of pesticides. Pesticides have

clearly become a key component of agricultural technology.

The use of pesticides in agriculture has provided numerous benefits in terms of
increased production and product quality. At the same time, pesticides are toxic chemicals
or in fact are poisons, and to avoid the toxic efi‘ects or to protect the health of human
beings, most countries have introduced laws governing not only the use of pesticides, but
also setting limits for the levels of pesticide residues which may be tolerated in foods
(Maybury, 1989). The US. is no exception and has been regulating the use of pesticides
since 1910: first by the US. Department of Agriculture; then by the Food and Drug
Administration under the 1938 revisions to the Food, Drug, and Cosmetic Act; again by
USDA under the 1947 Federal Insecticide, Fungicide and Rodenticide Act; and beginning
in 1970, by the Environmental Protection Agency. Although, the EPA regulates pesticide
use and sets residue tolerances, it is the FDA and USDA which monitor pesticide residues
in the food supply. The USDA is responsible for meat, egg, and poultry products only.

The role of pesticides in modern society has become an emotional and contentious
issue (Shibamoto and Bjedanes, 1993). Pesticide residues and microbial contaminants
head the list of consumer fears concerning the food supply. The public was very alarmed
by such incidents as the 1989 Alar scare, followed the same year by cyanide contaminated
grapes fiom Chile. The use of pesticides in agriculture can be expected to result in
residues in food (Lombarbo, 1989). It is therefore necessary to confirm that fresh and
processed fiuits and vegetables are free of excessive pesticide residues.

On August 3, 1996 a landmark pesticide food safety legislation was officially Signed
into law by President Clinton. This, the Food Quality Protection Act (FQPA), provides

some of the most significant changes in food safety and pesticide law in decades. The act

includes major revisions in the Federal Food, Drug, and Cosmetic Act (FFDCA) related to
food safety, as well as to pesticide registration and use provisions in the Federal
Insecticide, Fungicide, and Rodenticide Act (FIFRA). Key changes to the FFDCA
include: Repeal of the Delaney Clause; new procedures for approving tolerances and
modifying or revoking existing pesticide tolerances; added protection for infants and
children; consumer information is established; and EPA has the given option to consider
benefits in determining a safe tolerance. Key changes to FIFRA include: Reregistration of
pesticides on a 15-year cycle; faster review of reduced-risk pesticides; incentives to
develop and maintain minor uses; and a new definition of minor use. How this law will
impact current practices is not fully understood. Only time can tell

Increased public concern has led to increased monitoring of pesticide residues in fiesh
produce and processed foods. The National Food Processors Association (NFPA) has
long been serving the food processing industry and consumers by helping to assure the
safety, wholesomeness, and nutritional value of the nation’s food supply (Elkins, 1989).
The NFPA Protective Screen Program, introduced in 1960, was created to prevent illegal
and unnecessary residues in processed foods. Since then, NFPA in cooperation with the
food processing industry, has shown that residues are very infrequently encountered in
processed foods and when found they are present at levels lower than in the raw
agricultural product (Chin, 1991).

Since the 19605, the FDA has also been carrying out its own pesticide monitoring
program. The program has 2 principal approaches: (1) Regulatory or Commodity

Monitoring, to measure residue levels in domestic and imported foods to enforce

tolerances and other regulatory limits; and (2) the Total Diet Study, to determine intakes
of pesticides in foods prepared for consumption (Lombardo, 1989). Regulatory
Monitoring has focused on the raw agricultural commodity and annually collects and
analyzes about 15,000 samples for 253 different pesticides. The Total Diet Study
examines foods as eaten, covers only selected pesticides, and makes possrble the
determination of dietary intakes. The 1987 residue findings showed that out of 253
pesticides only 113 were detected. 'Less than 1% exceeded tolerances, and no residues
were detected in half the samples. The 1987 Total Diet Study determined that the
calculated dietary intakes were below the Acceptable Daily Intakes (ADI) established by
the World Health Organization (WHO).

In 1991 the Agricultural Marketing Service of the USDA implemented the Pesticide
Data Program (PDP) to collect objective, comprehensive data on pesticide residues for
fresh fiuits and vegetables (USDA, 1992). This program was designed to provide
government agencies with an improved data base to respond more effectively to food
safety issues. The primary recipient of the program’s data will be the EPA, which will use
the information to support its risk assessment process. The 10 most prevalently consumed
fruit and vegetable commodities in the U. S. were chosen as samples. Samples were
collected fiom six representative states, 25 other states, and 13 foreign countries. During
the first six months of 1992, a total of 2,859 samples were collected and analyzed. A total
of 42 different pesticides were detected in 1,664 (58%) of the samples. In general, the

levels of pesticide residues detected were substantially below tolerances.

B. Pesticides Involved

The two pesticides selected for this study were: Captan, a fungicide, and Guthion®, an
insecticide. The selection of these two pesticides was based on their importance in the
apple industry for control of major plant disease, insects, and mites. The pesticides were
also selected for their non-carcinogenic potential as indicated by the EPA

(l) Azinphosmethyl

Guthion® is the commercial name for azinphosmethyl The chemical name for
azinphosmethyl is 0,0-dimethyl S-[(4-oxo- l,2,3-benzotriazen-3(4H)-yl)methyl]
phosphorodithioate.

Azinphosmethyl is a nonsystemic organophosphorus insecticide which works as a
contact or ingestion poison. Azinphosmethyl was first introduced for use on cotton in
1956 in the US. It has since come into widespread use on fiuit as well as various field
crops and many vegetables. Azinphosmethyl’s wide use pattern requires it to be applied in
various formulations. It is used primarily for foliage applications and is applied mainly as a

spray (Chemagro Division Research Staff, 1974).

Figure 1 : Structure of Azinphosmethyl

Azinphosmethyl is also applied in combination formulations with other pesticides and
many important commercial formulations have been produced. Azinphosmethyl is known
to be compatible with most insecticides and fimgicides, including captan (Chemagro
Division Research Staff 1974). The pesticide products based on azinphosmethyl, alone or
in combination, have a broad spectrum of activity, especially against lepidopterous larvae,
bugs, sawfly larvae, fleas, scale insects, and aphids (FAO, 1991).

In terms of deciduous fiuits, azinphosmethyl has proved so effective against North
American insects that it often has been the only insecticide applied by many fiuit growers.
It should also be of great interest that despite its widespread use, few insects have shown
tolerances or resistance to azinphosmethyl (Chemagro Division Research Stafl‘, 1974).

(2) Captan

Captan is the common name for (N-trichloromethylthio-4-cyclohexane-1,2-
dicarboximide). It is a broad spectrum, non-systemic ftmgicide. Captan was first
introduced in the 1950s and since has attained very wide use on fiuit, vegetable,
ornamental, turf, and seeds. It is recommended for more diseases on deciduous fiuit than
any other fungicide (Vettorazzi, 1977). As a surface fungicide it is widely used for control
of scabs, blotches, rots, mildew, and other diseases on fiuits, vegetables, and flowers
(Wolfe et al., 1976). Captan is used in general purpose pesticide mixes and approximately
600 federally registered products contain captan as an active ingredient (Gilvydis et al.,
1986)

Captan has also been the subject of an EPA Special Review since 1980 because of
concerns over possible oncogenicity, mutagenicity, and other chronic efl‘ects (Gilvydis _et

al. , 1986).

Figure 2 : Structure of Captan

Captan has also been the subject of an EPA Special Review since 1980 because of
concerns over possible oncogenicity, nmtagenicity, and other chronic effects (Gilvydis et

al., 1986).

C. Pesticide Residues in Raw Fruits and Vegetables

The importance of pesticide use and the potential risk it poses has made information on
the presence of pesticide residues very important. Much of the data available regarding
residues in fruit and vegetable crops is obtained through large and small scale monitoring
programs and controlled field studies. Data fiom government pesticide monitoring
programs show that detectable residues are present in raw agricultural commodities.
Although most residues are within established tolerances, some are not, often because
there are no established tolerances for a specific chemical on that food (Petersen et al.,
1996)

Residue tolerances have been established for both captan and azinphosmethyl on a

great number of raw agricultural commodities in many different countries. In the US.
these tolerances are determined by the EPA under Section 408 of the Federal Food Drug

and Cosmetic Act (FFDCA). The maximum residues, from preharvest and postharvest

11

use or combinations of such uses, in or on apples is 2.0 ug/g for azinphosmethyl and 25
ug/g for captan (Code of Federal Regulations, 1996).

A pesticide is registered to control specific pests on specific crops as long as certain
conditions, such as application and timing, are met. The legal conditions for a pesticide
use are on the label and it is illegal to apply a pesticide in a manner not specified on the
label Residues that exceed tolerance values generally indicate pesticide misuse (Beall et
aL,l99l)

Residue levels in crops are dependent on a number of factors such as rate and
fiequency of application, nature of the plant surface, and weather conditions such as
rainfall, temperature, humidity, Stmlight, and wind. The pesticide and formulation in which
it is applied also greatly afl’ects the residues which are observed. The chemical makeup of
the pesticide may determine if it is loosely or tightly bound to the surface of the
commodity or if it will penetrate the surface and be translocated to inner tissues (Ritchey,
1986)

The preharvest interval (PHI), which is the time interval between the last spray
application and harvest, has been shown to affect residue levels. The PHI employed will
vary with the pesticide as well as the commodity. The pesticide manufacture will often
recommend a specific PHI, as well as rates and intervals in which to apply the pesticides,
in order to reduce the chance of residues on a commodity exceeding federal tolerances.
The label recommended preharvest interval (PHI) for azinphosmethyl, using 50 %
wettable powder (SO-WP) formulation, is 7 days for apples. The label specifies that
captan, using the 50 % wettable powder (SO-WP) formulation, may be applied to apples

up to the day of harvest (Crop Protection Reference, 1996).

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Azinphosmethyl does not penetrate to any appreciable extent into the physiological
processes of the plant (Chemagro Division Research Stafi, 1974). The compound does,
however, have an afinity for the cuticle waxes and oils which has a definite impact on the
various half-life values which have been observed The half-life for azinphosmethyl on
vegetable and forage crops grown under field conditions ranges fiom three to five days.
Azinphosmethyl persists on tree fiuits somewhat longer than on field crops. The average
half-life of azinphosmethyl on apples is six days.

Captan is a nonsystemic fungicide with low water solubility which results in it
remaining as superficial deposits on the surface of treated crops. This allows it to be
partly removed by water, especially on non-waxy crops such as strawberries (Vettorazzi,
1977)

In the 1992 PDP Report (USDA, 1992), which collected a total of 309 apple samples,
70 of the samples contained azinphosmethyl residues. The mean of the residues found was
0.1 ug/g which is only 5 % of the US. tolerance. Of the same 309 apple samples, 30 of
the samples contained captan residues with a mean residue level of 0. 15 ug/g or 0.60 % of
the US tolerance. The PDP Report also found that most of the pesticides detected were
below tolerance levels, but a high proportion of the samples had detectable residues
(Petersen et al. , 1996). This has been attributed to the use of much more sensitive
analytical methods.

Between 1978 and 1986, Ontario-grown apples were monitored for residues of a wide
range of pesticides used in their production (Frank et al., 1989). A total of 305 samples

were collected from both flesh market sources and fiom controlled atmosphere (CA) .

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storage. Both captan and azinphosmethyl were among the pesticides detected and were
used in production of 94.3 % and 91.2 % of the samples, respectively. Only 1.3 % of the
samples had detectable azinphosmethyl residues with levels averaging 0.26 i 0.10 ug/g
with 0.45 ug/g being the highest level detected. Captan residues were detected in 45.9 %
of the samples and averaged 0.089 :I: 0.119 ug/g with 1.00 ug/g the highest level detected.
A11 observed captan and azinphosmethyl residues were well below maximum residue limits
(MRL) permitted under the Canadian Food and Drug Act.

Frank et a1. (1991) studied the persistence of captan on apples, grapes, and pears in
Ontario, Canada. Captan was applied at 1.7, 2.8, or 3.4 kg ha'1 for 1-15 applications with
residues monitored over a 14-day period following the last application. Residues declined
significantly in seven of nine experiments. A correlation between rainfall and captan
residues was observed. The longest period required for residues to decline below 5 pg/g,
the maximum residue limit permitted under the Canadian Food and Drug Act, was 5 days
for grapes, 3 days for pears, and 7 days for apples.

Captan was sprayed 7 times at 7 day intervals and 4 times at 15 day intervals to
examine the degradation behavior on greenhouse tomatoes (El-Zemaity, 1988). Results
showed that captan sprayed at 7 day intervals was more persistent than sprayed at 15 day
intervals. Captan residues at 0 and 7 days after last application were determined to be
2.73, 1.96 ug/g for the 7 day interval and 1.84, 0.53 ug/g for the 15 day interval spray
program

Rashid et al.(1987) looked at captan residues on Golden Delicious apples when applied

at 2.4 g/l in a single treatment or as part of a standard treatment program with eight

14

applications. Samples were taken at midseason, 56 days after single treatment application,
and at harvest, 56 days following. Captan residues in the fiuit at midseason were 0.02,
5.7ug/g and at harvest were 0.01, 1.2 ug/g for the single and standard treatment,
respectively.

Fresh strawberries and grapes grown in Michigan and Indiana were surveyed for
captan residues (Gilvydis et al., 1986). Captan was applied by a number of difl'erent
methods and at amounts ranging from 0.5 to 6 lb formulation/acre. Last application dates
ranged fiom 2 days to nearly 5 months. Captan residues were found in all 28 of the
strawberry samples collected, ranging fiom <0.01 to 1.5 ug/g. Captan residues were
found in only 6 of the 15 grape samples treated’with captan, ranging fiom <0.0l to 0.082
ug/ g. Residue levels were found to be inconsistent with amount and dates of application,
most likely because of variations in weather conditions, especially rainfall.

Hansen et al. (1978) examined the pesticide residues found on apple and peach foliage
in an orchard spray program Azinophosmethyl and captan, the two pesticides of interest,
showed a 69% and 50% reduction, respectively, of residues following the tenth day of
post-application. There was no evidence of a buildup of either azinphosmethyl or captan
on treated foliage as the season progressed.

Azinphosmethyl residues were reported fiom several supervised trials with apples in
both the US. and Europe (FAO, 1991). Azinphosmethyl (50WP) was applied at a rate of
1.12-1.68 kg ai/ha in the US. rials and reported residues ranged from 0.07-1.69 ug/g after

a 7 day PHI.

15

Belanger et al. (1991) determined azinphosmethyl residues on apples in Canada at
different plant stages. Residue analysis revealed detectable residues on the foliage tmtil
mid season. However, negligible residue levels were found on the peel and the whole fiuit
at harvest.

Azinphosmethyl (50WP) was applied to field- grown grapes at maximum recommended
rate of pest control in Fresno County, California (Winterlin et al., 1974). Azinphosmethyl
residues were found on leaves at approximately 20% of their original levels 42 days after
initial application. Residue levels on the fiuit were 12, 14, and 4.4 ug/g after 28, 31, and

42 day PHI, respectively.

D. Pesticide Residues in Processed Fruits and Vegetables
The US. EPA, under Section 409 of the FFDCA, specifies tolerances for pesticide
residues in processed food. Section 409 tolerances are established only when a pesticide
is added indirectly or directly to a processed form of a food or concentrated to levels
exceeding those of the raw agricultural cormnodities as a result of processing. Ifthe
residues remaining in a processed food have been removed to the extent possible in good
manufacturing practices and do not exceed the tolerance on the raw product, the
processed product complies with Section 408 for raw agricultural commodities.
Concerns expressed about residues in processed foods frequently reflect a lack of
knowledge about food processing operations and their efl‘ect on residue levels. Processing
has been interpreted as any operation performed on a food, food source, or food product

from the point of harvest through consumption (Ritchey, 1981). Unit operations in

16

processing typically include washing the raw product with fairly large volumes of water,
frequently using high pressure sprays and often incorporating surfactants or other washing
aids; peeling the product mechanically with knives, abrasive discs or water; blanching with
hot water or steam; and in the case of canned foods, the cooking of the product at
temperatures at or above that of boiling water. Thus, the chemicals which may be present
are subject to not only physical removal by washing or peeling, but also acid or base
hydrolysis and thermal degradation (Chin, 1991). In almost all cases the net effect of
these operations is to reduce residues which may be on the raw product.

The amount of pesticide removed , if any, depends largely on the specific pesticide, the
commodity, and the severity of the processing operation. Pesticide residues loosely held
to the surface may be removed by washing or blanching, but residues which penetrate the
surface (systemic) are more dificult to remove (Ritchey, 1981). Peeling may also remove
residues confined to the surface but is often ineffective against those below the surface.
Systemic pesticides are typically registered for use early in the growing season so that
residual amounts at harvest are below tolerance (Beall et al., 1991). The extent to which
residues can be dislodged is also dependent upon the weathering of the residue on the
crop. Following the label recommended use of a pesticide along with the various food
processing methods available can help to achieve the desired residue levels.

The common consensus among those familiar with food processing methods is that
pesticide residues decrease, often dramatically, during processing and food preparation.
The NFPA has long been interested in the effect of commercial processing on pesticide

residues in food. Residue data, assembled in 1988 by the NFPA, on processed products

17

showed that of the 20,310 samples analyzed, 93% had no detectable residues (Chin,
1991). NFPA continues to collect data fiom the food industry in order to develop a sound
database on pesticide residues in processed foods.

The FDA Total Diet Study determines the intake of pesticides in processed foods or
table-ready foods. The study helps to determine dietary intakes of pesticides and then
compares these intakes with acceptable daily intakes (ADIs), as established by the WHO,
to identify trends. ADI refers to the level of daily exposure to a pesticide which, over a 70
year human life span, will have no negative efl‘ect. According to the 1987 Total Diet
Study report, the dietary intakes calculated were well below the established ADIs and by a
significant amount in most cases (Lombardo, 1989). The FDA continues to update this
program to reflect more recent food consumption trends and to continue providing
information necessary for the reassessment of pesticide uses and tolerances.

Pesticide residue data in foods are continually criticized for having too few samples,
covering too few pesticides, or having inadequate quality assurance documentation.
However, when taken as a whole, all of the databases consistently demonstrate that

pesticide residues are infiequently encountered in processed foods (Chin, 1991).

E. Common Pathways of Pesticide Residue Degradation

The degradation of pesticides can be classified as physical, chemical, and biological with a
combination of these factors influencing their breakdown over time (Coats, 1991). The
relative importance of these factors is highly dependent on a pesticide’s use pattern,

physical properties, and chemical structure as well as the nature of the treated plant

18

including physical characteristics of its surface, rate of growth, and factors causing erosion
of surface deposits. The degradation mechanisms affecting a pesticide in the field, when
applied to a crop for pest control, may difler from those affecting it during postharvest
treatment of the crop, as well as during processing. The following discussion of the
degradation of captan and azinphosmethyl will focus on the physical and chemical
pathways.

(1) Physical

The degradation or disappearance of a pesticide through physical means is of particular
importance to a pesticide in the field and may include wind, rain, heat, and light
(photolysis). Such environmental forces can have a significant eflect on a pesticide, the
sum of which has been termed ‘Sveathering”.

Frank et al. (1987) studied the effect of rainfall on the disappearance of captan fiom
tomatoes by comparing field grown tomatoes to greenhouse grown. Captan residues
declined significantly faster in the field and was directly correlated to rainfall Captan
residue study by Frank et al. (1985) showed similar results.

The eflects of sunlight on the degradation of azinphosmethyl were examined by Liang
and Lichtenstein (1976). Azinophosmethyl was applied to corn and bean leaves. The
control, exposed to darkness, was compared to samples exposed to Stmlight for 8 hours.
Results showed an 88% and 94% recovery of azinphosmethyl in the controls and an 86%
and 72% recovery in the light samples, respectively. The leaves exposed to darkness
showed no degradation products while those exposed to sunlight indicted the appearance

of N-methylbenzazimide on the corn leaves and N-methylbenzazimide sulfide,

19

benzazimide, and the oxygen analogue of azinphosmethyl on both corn and bean leaves.
Liang and Lichtenstein (1972) also showed that azinphosmethyl in aqueous solutions
formed organosoluble and water-soluble breakdown products in the presence of UV light
and to a lesser extent sunlight. The organosoluble products were identified as
benzazimide, anthranilic acid, methyl benzazimide sulfide, and N-methyl benzazimide,
whereas the water-soluble products remained unidentified.

Climatic conditions were shown to have a considerable influence on disappearance rate
of azinphosmethyl in or on oranges. Florida experiments (Chemagro Division Research
Stafl; 1974) showed a half-life of 46 days for oranges exposed to an average rainfall of 10
to 15 inches compared to a half-life of 340 to 400 days under the arid conditions
prevailing in California and Arizona (Gunther et al. , 1963 ). Gunther (1963) indicated
these results agreed with those reported by Williams in 1961 who demonstrated a
significant loss of azinphosmethyl from apple foliage with as little as 0.13 inch of rain.

The effect of wind and rain on emulsion sprays of selected organophosphate pesticides
(malathion, toxaphene, phosdrin, methyl parathion) was reported in 1958 by I-Iightower
and Martin using cotton plants (Ebling, 1963 ). Artificial wind was applied at 5 mph for 24
hours with 1/2 inch of artificial rain applied in three minutes. The percent reduction
resulting fiom wind ranged fiom 10% for nmlathion to 73% for phosdrin, respectively.
The percent reduction resulting fiom rain ranged fiom 25% for toxaphene to 76% for
malathion.

Work reported by Decker in 1950 and 195 8, on deciduous fiuits and forage crops

formd, with other factors being equal, there is a definite correlation between the vapor.

20

tensions of pesticides and the rates of the residue losses (Ebling, 1963). A majority of the
loss of more volatile compounds occurred in the course of their passage through the air
fiom the spray nozzle to the plant, as well as on the plant surface.

(2) Chemical

Pesticides may undergo a number of chemical transformations to include: hydrolysis and
other nucleophilic reactions, oxidation, isomerization, reduction, and free radical reactions
(Goring et al. , 197 5). Chemical oxidation and hydrolysis, two of the more commonly
observed chemical degradation pathways will be discussed further.

Chemical degradation of azinphosmethyl is assumed to occur primarily by hydrolysis,
but oxidation is also possible (Eto, 1974). Hydrolysis has been shown to be an important
mechanism of organophosphate degradation in both soil and aqueous environments (Freed
et al. , 1979). The hydrolysis of azinphosmethyl in sohrtion may proceed under acid,
neutral, and alkaline pH, but is generally more persistent under alkaline conditions (Faust
& Gomma, 1972). It was observed to have its greatest stability under acidic conditions
with an increasing rate of hydrolysis at higher pH. At pH 1.0, 3.0, 5.0, 7.0, and 9.0, the
tm values for azinphosmethyl were 24, 9, 8.9, 4.8, and 0.6 hours, respectively. Laing and
Lichtenstein (1972) reported azinphosmethyl to be relatively stable mrder neutral and
acidic conditions but at pH 11, 97% of the pesticide was converted to degradation
products such as anthranilic acid, benzazimide and 3 unidentified compounds.

Oxidation of azinphosmethyl dislodgeable residues on southern California citrus
foliage was reported by Gunther et al. (197 7). Azinphosmethyl-oxon levels never

exceeded 1.0% of the azinphosmethyl present. The oxon formed was more stable, but

21

dissipated rapidly following rainfall Degradation of azinphosmethyl through oxidation
was not found to be of significance during the relatively wet and humid summer months
normally experienced in the temperate eastern United States. Azinphosmethyl can be
converted to analogous phosphorothiolate by oxidizing agents (Zweig, 1964).

Wolf et al. (1976) reported on the susceptibility of captan to hydrolysis in water,
having a maximum half-life of 7 10 minutes in water. The hydrolysis of captan was pH
independent over the pH range 2-6 and pH dependent from pH 6 to 9. At pH 6,7 and
8.25, the half-life of captan was 250, 175, and 10 minutes, respectively. The products of
the reaction were identified as sulfur, chloride, and 4-cyclohexene-1,2-dicarboximide.
Aizawa (1982) similarly indicates the formation of 4-cylclohexene- 1,2-dicarboximide from
captan which is easily hydrolyzed via very unstable intermediates. Frank et al. (1983)
reported a half-life of less than one hour for captan at a pH of 8.5 in 22° C water and 13
hours at 5° C. At pH 5.5 the half-life was 13 hours at 22° C and 208 hours at 5° C.

Literature indicates that captan undergoes reactions of a hydrolytic nature or with
cellular thiols resulting in N-S bond cleavage and the release of tetrahydrophtalirnide
(THPI), tetrahydrophthalamic acid, and o-aminotetrahydrophthalimide. Epoxides of
captan and tetrahydrophthalimide are possible alteration products which may form under
conditions of weathering or degradative metabolism (Buyanovsky et al., 1988). The fate
of captan residues on Golden Delicious apples during normal processing procedures was
reported (FAO, 1991). Captan was converted to THPI during cooking in the production
of apple sauce or warm juice. In the preparation of cold apple juice, captan and THPI

partitioned into the pomace, with only minor residues remaining in the juice. Some of the

22

captan residue was converted to THPI during the production of dried apples. Captan and
THPI residue levels, measured in raw apples during a supervised field trial (FAO, 1991)
showed levels of 0.45, 0.87, and 1.5 ug/g for captan and < 0.05 ug/g for THPI following

28, 21, and 14 day PHI, respectively.

F. Effect of Processing on the Degradation and Removal of Pesticide Residues
Fruits and vegetables are often subjected to a number of different processing operations to
clean, eliminate waste, and to make the raw materials more palatable. While these
procedures may actually help reduce or remove pesticide residues, other proceSsing
methods have been specifically designed for such purposes. It is important to note that the
eflecfiveness of various processing operations in the removal of residues is dependent on
numerous vectors which include: the nature of the commodity being processed; the
pesticide used and its chemical properties, fornmlation applied, method of application,
rate of application; and the interaction of the pesticide with the commodity in terms of
contact time (Geisman, 1975). The net influence of processing almost always results in
residue levels in processed foods well below the tolerance for the raw product (Elkins,
1989)

Washing including rinsing is, perhaps, the one unit operation common to the
preparation of nearly all fiuits and vegetables for processing (Geisman, 1975). While
washing is a common practice among the processing industry, the specific methodologies
used vary from processor to processor. To help increase the effectiveness of a wash

treatment, physical and chemical aspects of the wash are manipulated to produce optimum

23

results. The following list of the physical and chemical aspects were employed during the
present study to examine their efl‘ectiveness in the removal of captan and azinphosmethyl
fiom apples: temperature, pH, chlorine, and detergent (sodium dodecyl sulfate). Data
pertaining to these processing methods was readily available in some cases and limited in
others.

(1) Temperature

Studies by Koivistoinen et al. (1965) showed the loss of captan in various preservation
processes depended chiefly on whether or not the process included a heating phase.
Boiling, steaming, autoclaving, or pasteurization generally resulted in a 98% to 100% loss
in captan residues. In the preparation of apple juice, 88% of captan was removed during a
mechanical pressing step with nearly complete removal being achieved during
pasteurization of the juice. A 90% loss of captan was observed in string beans blanched
for 2 minutes at 80° to 90° C.

The effect of temperature on both azinphosmethyl and captan were examined by Easter
and DeJonge (1985). The study evaluated the launderability of fabrics contaminated with
the two pesticides. The wash treatment compared the effect of three diflerent wash
temperatures and found an increase in temperature resulted in an increase in removal of
both pesticides.

Elkins et al. (1972) examined the ability of thermal processing to degrade or remove
pesticides fi‘om spinach and apricots. The selected products were fortified with 15
pesticides, including captan and azinphosmethyl, and subjected to processing temperatures

ordinarily encountered in canning. Sample analysis showed that thermal processing

24

degraded captan almost completely. A 93% and 97% decrease in captan residues was
observed as a result of thermal processing in spinach and apricot samples, respectively.
Similar results were found for azinphosmethyl with a 100% and 61% loss in spinach and
apricot samples, respectively. The observed captan and azinphosmethyl results were
found to be in agreement with those of Klayder ( 1963) and Carlin et al.(1966) who
determined that cann'mg, with the usual heat processing, largely destroys the pesticides on
raw produce (captan) and green beans (azinphosmethyl), respectively.

Faust and Gomma ( 1972) studied the eflects of temperature on the degradation of
azinphosmethyl, and showed the compound to be less stable as temperature increased.
Liange and Lichtenstein (197 2) similarly found that rapid degradation of azinphosmethyl
occurred above 37° C.

(2) Detergents

A 1967 report from the National Canners Association indicated that the use of detergents
improved the removal of various residues by washing procedures in potatoes, tomatoes,
and spinach (Liska and Stadelman, 1969). Fruits and vegetables are often subjected to
several immersion or spray washing operations followed by a detergent to aid in cleaning.
Several such detergents have been accepted as washing aids in produce destined for
canning.

A detergent was shown to significantly increase the removal of parathion fiom spinach
and broccoli (Elkins, 1989). Water washing reduced parathion residues by 9% and 0%
while detergent washing reduced residues by 24% and 33% in spinach and broccoli,

respectively. Similar results were determined in the 1960’s by the National Canners

25

Association (Chin, 1991). Parathion residues were Imsuccessfully removed fiom spinach
by a water wash. The incorporation of a detergent in the wash water increased the
removal of parathion fiom spinach by nearly three-fold over that removed by water alone.
Frank et al. (1983) studied the removal of captan fiom treated apples and found that while
thorough rinsing and wiping of apples removed 94% of captan residues the addition of a
detergent did not increase residue removal.
(3) PH
A number of studies have examined the efl‘ects of pH on both captan and azinphosmethyl
in solution. Faust and Gomma (1972) indicated that azinphosmethyl was less stable under
basic than acidic conditions, the half-lives of azinphosmethyl in buffered solutions at pH
1,3,5,6,7, and 9 maintained at 21° C were 24, 9, 8.9, 7.5, 4.8, and 0.6 hours, respectively.
Ong et a1. (1996) found similar results which showed azinphosmethyl to be stable in pH
4.5 and 7.0 solutions at 21° C and 44° C, with 96-100% (21° C) and 93-96% (44° C)
residual pesticide remaining after 31 minutes. Azinphosmethyl was found to be less stable
at pH 10.7 which decreased further with an increase in temperature and time.

Captan was reported to undergo degradation in water with a maximum half-life of half
a day (Wolfe et al., 1976). The reaction was reported to be pH independent over a pH
range of 2-6 and pH dependent from pH 6 to 9. The half life of captan was 250, 175, and
10 minutes at pH 6, 7, and 8.5, respectively. Similar results were reported by Ong et a1.
(1996) which indicated captan to be completely unstable in a pH 10.7 solution at ambient

temperature and 0 minutes. In pH 4.5 and 7.0 solutions, 47% and 42% of captan

26

remained for approximately 31 minutes at ambient temperature, respectively. Captan
stability decreased with increasing temperature (44° C).
(4) Chlorine
Chlorine and several of its derivatives are used extensively to disinfect nnrnicipal water
supplies, process and preserve foods, and sterilize equipment (Braude and Wade, 1983).
The use of chlorine in the oxidation of organic compounds has led to the investigation of
its capacity to degrade organic pesticides (Gomma and Faust, 1972). A limited amount of
data exists on the effects of chlorine on the pesticides azinphosmethyl and captan.
Suzumoto et al. (1983) reported on the degradation efl‘ects of chlorine on 13 different
pesticides in water, one of which was captan. The results showed that all 13 pesticides
were easily degraded by chlorine at concentrations of 1 ppm It was also shown that those
pesticides containing sulfur were degraded more easily. Captan at 0.04 ppm was degraded
only 5% after 24 hours in a 1 ppm chlorine solution.

Apples sprayed with captan and azinphosmethyl were dipped in a 50 and 500 ug/g
chlorine wash at ambient temperature for 15 minutes with constant agitation (Ong et al.,
1996). The apples were then analyzed for pesticides in the whole fruit and in applesauce.
The chlorine wash reduced captan and azinphosmethyl levels by 66% and 75% in the 50
ug/g solution and 77% and 83% in the 500 ug/g solution, respectively, when compared to
residues found on unwashed fiuit. Processing the apples into sauce further reduced
residue levels with degradation averaging 100% for captan and 98% for azinphosmethyl in
both chlorine solutions. Ong et al. (1996) also looked at the effects of chlorine on captan

and azinphosmethyl in solution. Results indicated that captan and azinphosmethyl were

27

rapidly degraded in 50 and 500 ug/g solutions of chlorine at low pH (4.5), but
degradation decreased at higher pH (10.7). It was determined that an increase in pH
decreased the percent HOCl, and consequently its reactivity with the pesticides. Both
chlorination levels decreased azinphosmethyl and captan by 80-100% after only 6 minutes.
Elevated temperatures further increased the degradation of the two pesticides in the
chlorinated water. The 500 ug/ g chlorine treatment proved the most effective in the

degradation of both pesticides.

MATERIALS AND METHODS

A. Orchard Study

(1) Orchard Applications

The experiment was conducted in a block of 23-year-old Golden Delicious cultivar trees
on M7a rootstock located on the Botany Research Field Laboratory at Michigan State
University, East Lansing, Michigan, each year of the three year study (1993 - 95). The
study required harvesting fruit with 7 day, 14 day, and 21 day preharvest intervals (PHI)
along with a Control The study plot was divided into 4 rows of trees, each representing
one of the four samples, with one buffer row located between individual samples. Refer to
the Field Plot diagram in Appendix 1. Maintenance pesticides were applied throughout
the growing season to provide the necessary insect, mite, and disease control. A final
Spray application of the test pesticides, at their recommend label rates (Guthion® 50W -
1.0 lb. ai/A, Captan 50W - 3.0 lb. ai/A), was made to give the appropriate PHI’S.
Application of the final spray was altered so that all samples could be harvested on the
same date. All pesticides were applied as a foliar spray with an FMC airblast sprayer at 80
gallons/acre and 300 psi. For the final application, the test pesticides were tank mixed and
applied as a Single application. Control samples did not receive a final application. Refer

to Tables 1-3 for records of the 1993-95 spray applications.

28

29

Table 1: 1993 Spray Schedule for Golden Delicious Apples

 

 

 

 

 

Apozlzd 2:11:33 “:27” Purpose of Application Plots Applied
Maintenance Spray Schedule
516/93 Rubigan IEC 0.1 apple scab 7 day PHI
Polyram 80W 2.4 apple scab all
Nova 40W 0.15 apple scab 14 8. 21 day PHI
Asana 0.66XL 0.04 leaf miner all
511 3193 Rubigan 1E0 0.1 apple scab 7 day PHI
Polyram 80W 2.4 apple scab all
Nova 40W 0.15 apple scab 14 8 21 day PHI
5126/93 Rubigan 1EC 0.07 apple scab 7 day PHI
Polyram 80W 2.4 apple scab all
Nova40W 0.11 apple scab 14821 day PHI
5128/96 Guthion 50W 1.0 curcullo, aphids all
617193 Guthion 50W 1.0 aphids, budmoth all
611 1193 Polyram 80W 2.4 apple scab all
Guthion 50W 1.0 aphids, budmoth all
6121193 Captan 50w 1.5 apple scab all
712193 Polyram 80W 2.4 apple scab all
Guthion 50W 1.0 coddlingmoth, leafroiler all
711 3193 Omite GE 1.9 european red mlte all
Lorsban 50W 1.0 coddllngmoth, applemaggot all
Polyram 80W 2.4 apple scab all
813196 Guthion 50W 1.0 coddlingmoth, applemaggot all
Captan 50W 1.5 apple scab all
Omite GE 1.9 european red mite all
Final Spray - Application of Test
Pesticides
9120/93 Guthion 50W 1.0 treatment spray 21 day PHI
Carzol 92$P 1.1 treatment spray 21 day PHI
Captan 50W 3.0 treatment spray 21 day PHI
9127/93 Guthlon 50W 1.0 treatment spray 14 day PHI
Carzol 92$P 1.1 treatment spray 14 day PHI
Captan 50W 3.0 treatment spray 14 day PHI
1014/93 Guthlon 50W 1.0 treatment spray 7 day PHI
Carzol 928P 1.1 treatment spray 7 day PHI
Captan 50W 3.0 treatment spray 7 day PHI

 

Harvest Date: October 11. 1993

30

Table 2: 1994 Spray Schedule for Golden Delicious Apples

 

 

 

 

 

M031: (1 2:33:32: ":3 A: A) Purpose of Application Plots Applied
Maintenance Spray Schedule
4130/94 Spray Oil GE 2961 1.6 gal mite and insect control all
Nova 40W 0.15 apple scab 14 8 21 day PHI
Rubigan 1EC 0.1 apple scab 7 day PHI
Polyram BODF 2.4 apple scab all
514194 Asana XL 0.66EC 0.04 leaf miner all
5110194 Nova 40W 0.11 apple scab 14 8 21 day PHI
Rubigan IEC 0.07 apple scab 7 day PHI
Polyram 800F 2.4 apple scab all
5/12/94 Streptomycin 17% 2 x .17 flreblight all
511 8194 Streptomycin 17% 2 x .17 firebllght all
5119194 Nova 40W 0.15 apple scab 14 8 21 day PHI
Rubigan 150 0.1 apple scab 7 day PHI
Polyram BODF 2.4 apple scab all
Guthion 50W 0.75 curculio, aphids all
5123194 Mycoshleld 17% 0.68 flreblight all
5127194 Nova 40W 0.15 apple scab 14 8 21 day PHI
Rubigan 150 0.1 apple scab 7 day PHI
Polyram BODF 2.4 apple scab all
Guthion 50W 0.75 curculio, aphids all
619194 Guthion 50W 0.75 aphids, budmoth all
Captan 50W 6 x 1.5 apple scab all
6116194 Sevin 80W 4.8 insects, fruit thinning all
Captan 50W 6 x 1.5 apple scab all
6123194 Guthion 50W 0.75 aphids, budmoth all
Captan 50W 6 x 1.5 apple scab all
711 1194 Guthion 50W 0.75 coddlingmoth. apple magot all
Captan 50W 6 x 1.5 apple scab all
7128194 Guthion 50W 0.75 coddllngmoth, apple magot all
Captan 50W 6 x 1.5 apple scab all
811 7194 Guthion 50W 0.75 coddlingmoth, apple magot all
Captan 50W 6 x 1.5 apple scab all
Final Spray - Application of
Test Pesticides
911 9194 Guthion 50W 1.0 treatment spray 21 day PHI
Camel 92$P 1.1 treatment spray 21 day PHI
Captan 50W 3.0 treatment spray 21 day PHI
9126/94 Guthion 50W 1.0 treatment spray 14 day PHI
Camel 92$P 1.1 treatment spray 14 day PHI
Captan 50W 3.0 neatment spray 14 day PHI
1013/94 Guthion 50W 1.0 treatment spray 7 day PHI
Carzol 928P 1.1 treatment spray 7 day PHI
Captan 50W 3.0 treatment spray 7 day PHI

 

Harvest Date: October 10. 1994

31

Table 3: Spray Schedule for Golden Delicious Apples

 

 

 

 

 

”0:626 2:33:32: "a?“ Purpose of Application Plots Applied
Maintenance Spray Schedule
4128/95 Nova 40W 0.15 apple scab 14 8 21 day PHI
Rubigan 150 0.1 apple scab 7 day PHI
Polyram BODF 2.4 apple scab all
515195 Nova 40W 0.11 apple scab 14 8 21 day PHI
Rublgan IEC 0.07 apple scab 7 day PHI
Polyram BODF 2.4 apple scab all
5112195 Asana 0.66XL 0.04 leaf miner all
511 7195 Streptomycin 1 7% 0.26 firebllght all
5126195 Nova 40W 0.15 apple scab 14 8 21 day PHI
Rublgan 1E0 0.1 apple scab 7 day PHI
Polyram BODF 2.4 apple scab all
Guthlon 50W 0.5 curculio, aphids all
611195 Sevin 80W 3 fruit thinning all
612195 NAA (20ppm) 0.01 fruit thinnlng all
619195 Captan 50W 1.5 apple scab all
Lorsban 50W 1.0 aphids, budmdlh all
6125196 Captan 50W 1.5 apple scab all
Guthion 50W 0.5 curculio, budmoth all
719195 Captan 50W 1.5 apple scab all
Guthion 50W 0.5 coddlingmoth all
711 9195 Omite 30W 1.5 mites all
7131195 Captan 50W 1.5 apple scab all
Guthion 50W 0.5 coddlingmoth, applemaggot all
811 8195 Captan 50W 1.5 apple scab all
Guthion 50W 0.5 applemaggot all
Final Spray - Application of
Test Pesticides
9118/95 Guthion 50W 1.0 treatment spray 21 day PHI
Carzol 92$P 1.1 treatment spray 21 day PHI
Captan 50W 3.0 treatment spray 21 day PHI
9125/95 Guthion 50W 1.0 treatment spray 14 day PHI
Carzol 92$P 1.1 treatment spray 14 day PHI
Captan 50W 3.0 treatment spray 14 day PHI
1012/95 Guthion 50W 1.0 treatment spray 7 day PHI
Carzol 92$P 1.1 treatment spray 7 day PHI
Captan 50W 3.0 treatment spray 7 day PHI

 

Harvest Date: October 9, 1995

32

(2) Sampling and Harvesting

Apples were hand picked at optinmm maturity, coinciding with the appropriate PHI’S,
from all regions of the tree except fiuit within one foot of the ground was excluded.
Harvest began about 9:00 AM and took approximately two hours to complete. Gloves
were worn during harvest and changed between each treatment to prevent cross
contamination. All four samples were collected on the same day with the Controls
collected first followed by 21 PH], 14 PH], and 7 PHI samples. Approximately 10-12
crates(50 -60 1b./crate) of fruit were collected fiom each of the four sample rows
Immediately following harvest, the samples were transported to a designated refiigeration
cubicle (2° C) for storage at the MSU Food Science and Human Nutrition building until
post harvest treatment and processing. Individual treatments and controls were separated
by sheets of plastic to prevent cross contamination during storage. Samples for 1993-95
were harvested on October 11, 10, and 9, respectively. Sample processing for 1993 took
place October 20, 21, 26, 28 of 1993. Similarily, processing took place October 18-
21,1994 and October 19-22, 1995.

(3) Fruit Post Harvest Treatments

All post harvest treatment and processing were conducted at the Fruit and Vegetable
Processing Laboratory, Department of Food Science and Human Nutrition, Michigan
State University, East Lansing, Michigan. The Golden Delicous apple samples were
subjected to a series of post harvest wash treatments and two wash times. Each of the
treated samples were processed into four different products. Post harvest treatment and

processing was done over a four consecutive day period. One sample type was treated

33

and processed each day starting with Control and followed by 21 PHI, 14 PHI, and 7 PHI.
All samples were prepared in triplicate except for the Controls where only one replicate
was prepared for analysis.

Three reps of 8 apples each were removed fiom all 4 sample types prior to postharvest
treatment and processing. The apples were placed in plastic bags and immediately fiozen
for analysis and to serve as the unwashed, Improcessed controls for each treatment.

a. Post Harvest Wash Preparation

The Golden Delicious apples were subjected to six different wash treatments to
determine their eflectiveness on removal and degradation of the test pesticides. The six
wash treatments were: (1) 21°C and pH 7; (2) 21°C and pH 11; (3) 43°C and pH 7; (4)
43°C and pH 11; (5) 21°C and pH 7, 500 pg/g Chlorine; (6) 21°C and pH 7, 2% Sodium
Dodecyl Sulfate (SDS). Five minute and 15 minute wash times were employed to study
the effects of wash duration.

All wash treatments were prepared in 20 liter volumes to allow for complete
submersion of the apple samples. Tap water at 21°C was used to prepare Treatments #1.
Tap water for Treatment #2 was placed in a steam heated vessel and brought to 43° C.

Treatments #2 and #4 were prepared using deionized water. The treatments were both
brought to pH 11 with the addition of 1.00 N NaOH solution (Columbus Chemical
Industries, Inc. ). A cah'brated pH meter, model 601A (Corning Glass Works, Medfield,
MA), was used to determine the pH of the wash treatments. Treatment #4 was placed in a
steam heated vessel and brought to 43° C while Treatment #3 remained at 21°C.

Chlorox Bleach, which contains 5.25% NaOCl by weight, was added to 21°C and pH 7

deionized water to provide a 500 ug/ g solution of chlorine for Treatment #5.

34

Treatment #6, 2% SDS solution, was prepared by adding 400 g of Electrophoretic
Grade SDS (Boehringer Mannheim Co.) to 19.6 L of 21°C and pH 7 tap water.

b. Post Harvest Wash Treatment

Apple samples for each of the six post harvest washes (PHW) were divided in half and
placed in separate mesh bags. The use of mesh bags allowed samples to be easily removed
after the 5 minute wash time had expired. Each onion bag contained 3.4 to 3.9 Kg of
apples.

Once the wash treatments were prepared, two bags of apples were placed in each of
the six PHW. The apples were kept submerged , without agitation, during the duration of
the wash. After 5 minutes one bag of fruit was removed from each of the six PHW. The
second bag remained submerged an additional 10 minutes before removing. When
samples were removed from the wash treatments they were rinsed with tap water prior to

processing. Table 4 shows the samples prepared during the PHW treatments and the

sample identification assigned to each.

Table 4: Postharvest Wash Treatment Samples

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A1 B1 C1 D1 E1 F1

A2 32 c2 oz 52 F2

A3 33 c3 03 53 F3

A4 B4 C4 .... D4 E4 F4

A5 85 C5 ‘ ‘ DS E5 F5

A6 36 C6 06 E6 F6
§Sam2|e I. D. 5
§A= 7 dayPHl 5 minute wash time D =7dayPHl, 15 minute wash time
§B= 14 dayPHl 5minute wash fime E= 14 dayPHl, 15 minute wash time
;C= 21 dayPHl, 5 minute wash time F= 21 dayPHl. 15 minute wash ime ;

 

31-6= Wash Treatments #1 through #6

 

35

(4) Fruit Processing
Each PHW treated sample listed in Table 4 was divided into four parts to be processed as:
juice; peeled, fiozen slices; sauce from unpeeled, uncored apples (Gerber Process); and
sauce from peeled, cored apples. The two types of sauce represent products currently
being manufactured and were expected to differ in residue level The following weights of
apples were required during processing to ensure suficient product was available for
residue analysis: 1.33-1.44 Kg, peeled sauce; 0.95-1.0 Kg, unpeeled sauce; 0.55-0.66
Kg, juice; 0.66-0.77 Kg, slices. The apples were processed using the following Standard
Operating Procedures developed by the Food Science and Human Nutrition Department,
Michigan State University, East Lansing, Michigan:

a. Apple Slices

Weighed apple samples were peeled and cored on a Leader apple peeler. The peeled
and cored fiuit was sliced with a Sunkist slicer. The apple samples were transferred into
ziplock bags, weighed, labeled and immediately placed in -20° C storage to await residue

b. Apple Juice, 1993 Method

Weighed apple samples were macerated in a Hobart Food Chopper (Hobart MFG. Co.,
Troy, OH). The macerated apple tissue was placed on a nylon press cloth and pressed
with a hydraulic press to express the juice. The juice volume was measured, poured into
labeled 12 oz french square glass bottles, and placed immediately in -20° C storage to

await residue analysis.

36

c. Apple Juice, 1994 & 1995 Method

Weighed apple samples were sliced with a Sunkist slicer. The apple slices were put
through an Acme Juicerator. The grinder/centrifuge basket of the Acme Juicerator was
lined with one layer of Kimwipe tissue. The apple slices were introduced into the
juicerator through the opening in the top and automatically ground, juiced, and filtered.
The vohtme of juice was measured, placed in labeled 12 oz french square glass jars, and
immediately placed in -20° C storage to await residue analysis.

(1. Apple Sauce, Peeled and Unpeeled

Weighed samples of apples intended for peeled sauce were peeled and cored with a
Leader apple peeler. The peeled and cored samples were sliced with a Srmkist slicer.
Weighed samples of unpeeled, uncored apples were sliced with the Srmkist slicer to be
used for unpeeled sauce. Apple slices were placed in a single layer on a stainless steel tray
for steaming in a Dixie blancher. Each tray of apple slices was steamed for 10 minutes to
adequately soften the fiuit and inactivate enzymes. After steaming, the fiuit was cooled in
air for l to 2 minutes before grinding and finishing in a Langsencamp pilot plant finisher
with a 0.033-0.045 inch screen to remove coarse fibers, seeds, stems, and peel particles.
The applesauce samples were placed in ziplock bags, labeled, weighed, and immediately

placed in -20° C storage to await residue analysis.

B. Sample Extraction and Cleanup
(1) Reagents
All organic solvents used for preparaton of pesticide stock solutons, sample extraction,

and cleanup were distilled-in- glass grade. Acetone and methylene chloride were obtained

37

fiom Mallinckrodt, Co. (Paris, KY) and hexane and acetonitrile were obtained fiom EM
Science, Inc. (Gibbstown, NJ).

(2) Chemicals

Azinophosmethyl and captan standards were obtained from AccuStandard, Inc. (New
Haven, CT). The stock solutions and working standards of azinphosmethyl and captan
were prepared in hexane and stored in a freezer. Reagent grade anhydrous sodium sulfate
was used during sample extraction.

(3) Glassware

All glassware was thoroughly washed with detergent and warm water then rinsed with
distilled water. The glassware was then rinsed once with acetone before being placed in
an oven overnight before use.

(4) Extraction and Cleanup

Both azinophosmethyl and captan were extracted from the raw and processed apple
samples with a modificaiton of the method described by Liang and Lichtenstein (1976). A
50 g sample size was used for all sample extractions. Applesauce was blended with 100
ml of acetone for 3 minutes using a Pro 200 hand held homogenizer. (Both apple slices
and raw apple samples were macerated with a Hobart food chopper before they could be
blended with acetone. Apple juice samples did not require the blending and filtering step
and were added directly to the 500 ml separatory ftmnel with acetone.) The sample was
filtered under vacuum through a ceramic buchner firnnel containing Whatman #1 filter
paper. The filter cake was rinsed twice with 10 m1 of acetone. The filtrate was

transferred to a 500 ml separatory funnel and extracted twice with 100 mL and 50 ml of

38

methylene chloride. The methylene chloride extracts were collected through a glass funnel
containing a glass wool plug and anhydrous sodium sulfate into a 250 ml round bottom
flask. The extract was evaporated to dryness with a roto-vap evaporator. The dried
sample was redissolved with 50 m1 of hexane and poured through a glass ftmnel containing
a glass wool plug and anhydrous sodium sulfate into a 250 ml separatory fimnel The
rornrd bottom flask was rinsed with an additional 50 mL of hexane and transferred to the
separatory funnel The hexane was partitioned with 3 x 25 ml portions of acetonitrile.
The acetonitrile extracts were combined in a turbo-vap tube and evaporated to dryness.
The residue was redissolved in 5 ml of hexane, transferred to a 4 dram glass vial, and
placed in the freezer to await GC analysis.
(5) Gas Chromatographic Analysis

a. Azinophosmethyl

Azinphosmethyl residues were detected and quantified using a Hewlett Packard Series
H 5890 gas chromatograph equipped with a Nitrogen Phosphorus Detector (NPD). The
GC was equipped with a DB-5 fused silica capillary cohtmn (30 m x 0.25 mm id.) with a
0.25 micron film thickness (J.W. Scientific, Folsom, CA). The oven temperature was
programmed isothermally at 230° C, while the injector and detector temperatures were
both set at 250°C. Helium and nitrogen were used as the GC carrier gas and makeup gas,
respectively. Hydrogen and air were used as the detector gases. The injection vohrme
was 3 ul and samples were injected with a HP 7673 automatic sampler linked to the GC.

Integration was carried out with HP Chemstation software interfaced to the GC.

39

b. Captan

Captan residues were detected and quantified using a Hewlett Packard Series II 5890
gas chromatograph equipped with a Ni°3 Electron Capture Detector (ECD). The GC was
equipped with a DB-S fused capillary (60 m x 0.25 mm id.) with a 0.25 micron film
thickness (J .W. Scientific, Folsom, CA). The oven temperature was programmed
isothermally at 180° C, while the injector and detector temperatures were 220° C and 275°
C, respectively. Helium and nitrogen were used as the GC carrier gas and makeup gas,
respectively. The injection volume was 2 pl and samples were injected with a HP 7673
automatic sampler linked to the GC. Integration was carried out with HP Chemstation
software interfaced to the GC.
(6) Calculation of Pesticide Residue Concentration
Pesticide residue concentrations were calculated by comparing the integrated area of the
identified pesticide peak found in the sample to a standard curve of that pesticide. Both
captan and azinphosmethyl standards, for GC use, were prepared in hexane at
concentrations in the range of 0.05 ug/g to 4.0 ug/g for azinphosmethyl and 0.05 ug/g to
2.0 ug/g for Captan. Using Microsoft Excel (Microsoft Corporation, Redmond, WA)
software, a linear regression standard curve of each pesticide was obtained by plotting the
standard concentration against its integrated peak area. Appendix 2 and 3 show examples
of the standard curves for azinphosmethyl and captan, respectively. The concentration of
each pesticide residue was calculated as ug/g using the following formula:

Conc. of pesticide in sample extract based on s_td. curve Luglg) x Vol. final extract 4 5 m1)
Weight of sample analyzed (50 g)

4O

(7) Method Recovery Study

Recovery studies for azinphosmethyl and captan were carried out in triplicate using the
above desribed analytical methods. The recovery samples were prepared by adding a
known amount (Spike) of each pesticide to a 50 g sample of apple (juice, sauce, slice) and
taking each sample through the entire analytical method. Recovery study samples were
spiked at a level of 0.2 and 2.0 ug/g for both captan and azinphosmethyl.

(8) Method Detection Limit Study

Method Detection Limit (MDL) studies were carried out for both captan and guthion in
apple samples (sauce, juice, slices). MDL was accomplished by spiking known amounts
of each pesticides into 50g samples at a range of concentrations (pg/g) and determining
the minimum level at which each pesticide

could be detected in a particular sample type. Postive detection required a peak response
height 3 times the baseline noise height. MDL samples were done in triplicate and taken
through the entire analytical method.

(9) Statistical Analysis

Means and standard deviations for all samples were calculated using Microsoft Excel 5.0.
All sample determinations were made in duplicate except method recovery and method
detection limit samples which were done in triplicate. Systat 7 .0 was used to calculate
significant diflerences between treatment means using a paired sample t test. Statistical
outliers in the data were determined and eliminated using the test proposed by Grubbs

(1969)

RESULTS AND DISCUSSION

A. Chromatographic Analysis

(1) Azinphosmethyl

The pesticide azinphosmethyl was detected using gas chromatography linked to a nitrogen
phosphorus detector (NPD). The compound appeared as a single peak with a retention
time of 8.9 minutes. Figure 3 shows a typical Chromatogram of an azinphosmethyl
standard while Figure 4 illustrates the chromatogram of azinphosmethyl detected in an
actual sample. A typical standard curve for am'nphosmethyl can be found in Appendix 2
and is representative of those used to calculate azinphosmethyl concentrations in sample
extracts. Regression analysis was utilized to determine standard curve linearity, with a
correlation coefiicient (R2) of >0.9 being the criteria for acceptance.

Recovery study samples for azinphosmethyl were spiked at a level of 0.2 and 2.0 ug/g.
Table 5 gives the percent recoveries obtained for azinphosmethyl in apple samples (juice,
sauce, slice). Control samples originally produced during each year of the study were
found to contain residues of azinphosmethyl. Thus the apple samples used for the
recovery studies were commercial apple products obtained through the Michigan State
University stores. Only one type of applesauce was obtained to represent both unpeeled
and peeled applesauce. The method detection limit (MDL) for azinphosmethyl was

determined to be 0.02 ug/g in all sample types. Similarly, the percent recoveries at MDL

41

42

8400-
8200-

8000-

am7

7800-

 

7600-

 

7400-

7200-

 

 

r

O 14

Figure 3: GO Chromatogram of an Azinphosmethyl Standard
1) 1.0 ppm standard
2) Rt=8.917 minutes

43

7800-

7600—

7400‘-

7200—

8.927

7000-

6800-

 

eeoo-h‘l

 

 

 

Figure 4: GO Chromatogram of an Azinphosmethyl Sample

1) 1993 Apple Juice, 7 day PHI, 43°C and pH 7, 5 minute wash time
2) Rt=8.927 minutes

44

are listed in Table 5. High recoveries for azinphosmethyl, listed in Table 5, were obtained
for all three products but were highest in applesauce and apple juice. Recoveries greater
than 100% represent both analytical error and matrix enhancment of the residues.
Recoveries appeared to decline for all sample types when spiked at a lower level. The
lower recoveries may be a result of matrix afi‘ects or extraction eficiency. Samples which
contain low levels initially, are more likely to show these discrepancies. Apple slices had
lower recoveries overall. This slight decline in recovery may be a direct result of the more
involved extraction process required for apple slices, which required one more step in the

extraction process than applesauce and two more than apple juice.

Table 5: Azinphosmethyl and Captan Recovery Study

 

 

" Azinphosmethyl " Captan
Sample (MDL) (MDL)
Type 0.02 ug/g 0.2 uglg 20 u 0.02 912 0.2 u 20 u

 

I Sauce K15 +l- 6.3% %.7 +l- 5.8% 102 +/- 2.9% 5.2 +l- 8.5% $0 +I- 5.0% $0 +1- 5.0%
I Slice 87.1 +/- 7.6% 95.0 +l- 5.0% 96.7 +/- 2.9% 87.0 +I- 6.0% $3 +l- 2.9% %.3 +1- 7.6%

l Ju'ce 92.9 +/- 4.7% 93.3 +/- 2.9% 102 +1- 2.9% Q13 +/- 5.0% $3 +/- 5.8% 1CD +l- 5.0%
' Each value represents a 3 rep average

 

 

 

 

 

 

 

 

 

 

(2) Captan

The pesticide captan was detected using gas chromatography linked to an electron capture
detector (ECD). The compound appeared as a single peak with a retention time of 9.2
minutes. Figure 5 shows a typical chromatogram of a captan standard while Figure 6
illustrates the chromatogram of captan detected in an actual sample. A typical standard
curve for captan can be found in Appendix 3 and is representative of those used to

calculate captan concentrations in sample extracts. Regression analysis was utilized to_

45

5000—

4800-

4600-

4400-

9.201

4200-

4000-

d
q
d

3800-

 

 

 

 

Figure 5: GO Chromatogram of a Captan Sample
1) 0.8 ppm standard
2) Rt=9.201 minutes

46

5000—

4800-

 

 

4600-

 

 

4400-

4°200-

9.206

4000-

in

13800-

 

 

 

Figure 6: GO Chromatogram of a Captan Sample

1) 1995 Apple Slice, 14 day PHI, 21°C and pH 7, 15 minute wash time
2) Rt=9.206 minutes

47

determine standard curve linearity, with a correlation coeficient (R2) of >0.9 being the
criteria for acceptance.

Recovery study samples for captan were spiked at a level of 0.2 and 2.0 ug/g. Table 5
gives the percent recoveries obtained for captan in apple samples (juice, sauce, slice).
Control samples originally produced during each year of the study were found to contain
residues of captan. Thus, the apple samples used for the recovery studies were
commercial apple products obtained through the Michigan State University stores. Only
one type of applesauce was obtained to represent both unpeeled and peeled applesauce.
The method detection limit (MDL) for captan was determined to be 0.02 ug/g in all
sample types. The percent recoveries at MDL are listed in Table 5. Sirnilarily, high
recoveries were also obtained for captan in all sample types. Recoveries again declined in
all sample types when spiked at a lower level The lower recoveries most likely resulted
from the same factors which affected azinphosmethyl.

B. Pesticide Residues in Unprocessed Apples

During all three years (1993-95) of the study, Golden delicious apple trees were sprayed
with the test pesticides, Captan and Azinphosmethyl, at their recommended label rates.
Final spray applications were altered to obtain apples with preharvest intervals (PHI) of 7,
14, and 21 days so that all PHI treatments could be harvested on the same date at
optimum maturity.

(1) Preharvest Interval Study

PHI represents the time interval between the last spray application and harvest. Previous

studies indicate that longer PHI’s help to lower pesticide residue levels. El-Zamity (1988)

4s

and Rashid et.al (1987) both reported lower residue levels for captan, with an increase in
PHI, on tomatoes and apples, respectively. Similar studies by El-Hadide (1993) and
Belanger et.al (1991) found residue levels to decrease with an increase in PHI when
looking at azinphosmethyl on apples. Pesticide manufacturers often recommend a specific
PHI in combination with a particular crop and pesticide. Such recommendations help to
reduce the chance of residues exceeding federal tolerances. According to the 1996 Crop
Protection Reference, the recommended PHI for azinphosmethyl (SO-WP formulation) is 7
days for apple while captan (SO-WP formulation) may be applied up to the day of harvest.

Residue analysis of azinphosmethyl in raw apple samples at 7, l4, and 21 day PHI,
indicated patterns not consistent with data fiom previous studies. Figure 7 shows the
average residue levels during 1993-1995. As indicated by previous studies, residue levels
can be expected to decrease with an increase in PHI. Only during the 1994 season did
residue levels follow the expected pattern. As for 1993 and 1995 seasons, the largest
residue levels showed up during the 14 day PHI for both years, followed by the 7 day and
21 day PHI, respectively.

Residue analysis for captan , Figure 8, indicated similar findings. The 1994 season
follows the pattern of decreasing residue with an increase in PHI. As for 1993 and 1995
data, we see a pattern very similar to that observed for azinphosmethyl

The cause of the residue patterns in Figure 7 and 8 for 1993 and 1995 data years is
unknown. As indicated, the residue patterns observed for the two pesticides were very
similar during all three years of the study. Most likely those factors which aflected the

patterns noted in one pesticide came into play for the other pesticide. Factors which may

49

 

 

 

1993 Data

Azinphosmethyl
Residue (rig/g)
.0 .0 .0
a a on -

.0
re

 

Control 7 day PHI 14 day PHI 21 day PHI
Sample and Treatment (2 Rep Ave.)

 

 

 

1994 Data

Azinphosmethyl
Residue (ugly)
.0 .0 .0
A O on

.0
N

 

Control 7 day PHI 14 day PHI 21 day PHI
Sample and Treatment (2 Rep Ave.)

 

NA=NotAnaIyzed

 

 

1 995 Data

Azinphosmethyl
Residue (rig/g)
.0 .0 .0
A a: or

.0
N

 

Control 7day PHI 14 day PHI 21 day PHI
Sample and Treatment (2 Rep Ave.)

 

Figure 7: Azinphosmethyl Residues in Raw Apple

 

 

50

 

 

 

 

 

 

1993 Data
15
a
3.
3
I!
8
a:
E
ii
0 Control 7 day PHI 14 day PHI 21 day PHI
Sample and Treatment (2 Rep Ave.)
1994 Data
g .
3.
O
i
8
a:
B
i
a
o

 

Control 7 day PHI 14 day PHI
Sample and Treatment (2 Rep Ave.)

21 day PHI

 

" NA = Not Analyzed

 

 

Captan Residue (rig/g)

1995 Data

 

Control 7 day PHI 14 day PHI
Sample and Treatment (2 Rep Ave.)

Figure 8: Captan Residues in Raw Apple

21 day PHI

 

 

 

51

have contributed to these unexpected results include the efl‘ects of weather during or alter
the time of spray, the spray program itself, or any combination of these factors.

We can speculate on the potential of spray drift to be a factor. Numerous reports
show that in virtually all pesticide applications, a fraction of released material drifts away
from the target site and settles downwind of the application (Salyani et.al, 1991). A study
by Salyani et.al (1991), which included air blast Sprayers, similar to that used in this
project, indicated the potential for drift up to 195 m downwind. Referring to Appendix 1,
the field plot diagram, only one buffer row exists between each treatment. Further, the 14
day PHI sample row is located directly between the 7 day and the 21 day PHI sample rows
which would have the potential of collecting drift from both of the adjacent row of trees.
The close proximity of the three treatments, particularly the location of the 14 day PHI
samples, make spray drift a potential problem This may help to explain why the 14 day
PHI samples, during the 1993 and 1995 spray season, contained the highest residue levels
for both pesticides. Unfortunately, this does not explain why 1994 residue levels followed
the expected residue trend in respects to PHI.

Information regarding weather conditions during the 1993-95 growing seasons was
collected by field stafl‘ at the Botany Research Field Laboratory, Michigan State University
and entered into a Residue Study Field Report for this particular study. The weather data
collected included: precipitation records prior to the application of the final spray
program and extending through harvest; as well as conditions observed during the final
spray applications themselves, which included wind, temperature, and other general

observations. The only weather condition which showed a potential for disrupting the

52

spray treatment or which could have resulted in the erroneous results observed in the PHI
data, was the that of rain. Rain is one of the weather conditions that can significantly
afl‘ect the environmental fate of foliar-applied pesticides (Willis et al., 1994).

According to the Residue Study Field Report for 1994, 0.72 inches of rain followed the
14 day PHI final spray application. The amount of elapsed time between pesticide foliar
application and initial rainfall can dramatically afl‘ect pesticide persistence, efficacy, and
runofl‘ losses (Willis et al., 1994). It is possible that the rain may have afi‘ected this
particular application. If so, this may help to explain why the 14 day PHI residues, in
1994 raw apples, were not higher than the 7 day and 21 day PHI residue as observed
during 1993 and 1995. This supports previous speculations regarding spray drifi, which is
being considered as the cause of the residue patterns observed in 1993 and 1995 raw apple
data, Figures 7 and 8. Previous studies by Northover et al. (1986), Smith and MacHardy
(1984), Gunther et al. (1963 ), and Willis et al. (1994) indicate both pesticides to be

susceptible to losses during rainfall.

Table 6. Azinphosmethyl and Captan Residues in Raw Apples

 

 

 

 

Data Year * Azinphosmethyl (uglg) * Captan (ug/g)
1993 0.57+I- 0.34 1.67 +I- 1.1
1994 0.14 +/- 0.03 0.71 +l— 0.18
1995 0.27 +/. 0.14 1.12 +I- 0.54

 

 

 

 

 

* These values represent the average residue for 7,
14, and 21 day PHI treatments in rawapples

Due to the results indicated above, the effects of PHI on processed apple products will not

be discussed. It was determined that the best results could be obtained by averaging the 7,

 

53

14, and 21 day PHI for each year, which will serve as a comparison between the raw apple
residues and processed apple residues. Table 6 lists the averaged vahres for both captan
and azinphosmethyl residues in the raw apple during all three years of the study.

(2) Residue Levels in Raw Apples

Referring to Figures 7 and 8, the overall residue levels fluctuated fiom year to year for
both pesticides and with a striking similarity. Residue levels were at their highest in 1993
and lowest in 1994 for both pesticides even though the same spray schedule was used
during all three years of the study. The method of application, the PHI employed, stage of
apple development at harvest, and dates of application and harvest varied little from year
to year. It is conceivable that the same factors which affected the PHI data may have
come into play here as well.

Despite the variance in residue levels between study years, both azinphosmethyl and
captan levels were well below the tolerances levels determined by the EPA under section
408 of the FFDCA The maximum residues from preharvest and postharvest use or
combination of such uses, in or on apples is 2.0 ug/g for azinphosmethyl and 25 ug/g for
captan (Code of Federal Regulations, 1996). The highest value observed for
azinphosmethyl in raw apples was 0.925 ug/g which is over 50% lower than the maximum
allowable residue. The highest value observed for captan was 2.873 ug/g and is 88.5%
lower than the maximum allowable residue for captan. The highest residues for both
pesticides were found in 1993 raw apples with a PHI of 14 days. The lowest residues

noted for azinphosmethyl and captan in raw apples were 0.115 ug/g and 0.527 ug/g,

54

respectively. Both of these low values were observed in 1994 raw apple data for 21 day
PHI and represent 5.75% and 2.11% of the maximum allowable residues for
azinphosmethyl and captan, respectively.

These data did not give consistent results from year to year in terms of residue levels.
It may however, indicate that those factors afl‘ecting pesticide residues in the field can not
be counted on to give repeat performances fi'om year to year.
(3) Product Yield
During all three years of the study, with the exception of apple juice, the processing
methods employed were the same. Table 7 lists yield data for all three years of the study.
Apple juice prepared during 1993 was processed using a different method than during
1994-95. Due to this change in procedure apple juice yield in 1993 was lower than 1994
and 1995. Yield data can be expected to vary from year to year. This may be a result of a
number of factors including: apple size, apple shape, and the efliciency of the processing
method. Average apple size can vary between years and is affected by the individual
growing season. Although a majority of apples have uniform shape, those apples altering
fiom that mold may not be peeled or cored with the same efficiency. This may result in
portions of peel and core not being removed or the removal of the apple flesh. These
factors were readily observed during the processing phase. Applesauce yields are lower
than the other processed fractions because of the number of unit operations neccessary to
produce this product and declines with each of the following processing steps: peeling

and coring (peeled applesauce only), slicing, blanching, and finishing.

55

Table 7: Yield Data for 1993-1995

 

 

Sampling Raw Apple Wt Product Wt

 

 

 

 

 

 

Product Year (Kg) (Kg) Yield
Unpeeled Applesauce
1993 0.82 +I- 0.16 0.33 +I- 0.09 0.41 +I- 0.04
1994 1.00 +/- 0.07 0.40 +/- 0.01 0.40 +l- 0.03
1995 0.88 +I— 0.12 0.39 +/- 0.09 0.44 +/- 0.05
Peeled Applesauce
1993 1.61 +/- 0.25 0.37 +I- 0.07 0.23 +I- 0.02
1994 1.42 +/- 0.05 0.39 +/- 0.06 0.27 +I- 0.02
1995 1.44 +I- 0.07 0.44 +I- 0.08 0.31 +I- 0.02
Apple Slice
1993 0.58 +/- 0.09 0.40 +/- 0.18 0.69 +1002
1994 0.74 +/- 0.12 0.54 +l- 0.09 0.73 +I- 0.02
1995 0.80 +I- 0.12 0.62 +I- 0.09 0.77 +/- 0.01
Sampling Raw Apple Wt Product Vol Yield
Product
Year (Kg) (ml) (mllKg)
Apple Juice = =
1993 1.59 +l- 0.27 643 +I- 133 404 +I- 64
1994 0.57 +/- 0.06 408 +I— 65 710 +/- 71
1995 0.62 +I- 0.07 396 +/- 38 640 +/- 46

 

56

C. Azinphosmethyl Residue Study
The following sections will discuss the residue studies which were set up to examine the
effects of individual postharvest wash treatments and their ability to reduce or eliminate
azinphosmethyl residue in finished apple products. The raw data pertaining to
azinphosmethyl residues in peeled applesauce, mpeeled applesauce, apple juice, and apple
slices is contained in Appendices 4, 5, 6, and 7, respectively. These data are illustrated in
the Figures 9 - 44. Only those findings which were calculated to be statistically significant
are discussed.
(1) Postharvest Wash Treatment Variables

Postharvest wash treatment variables were examined to determine their efl‘ect on the
removal or degradation of azinphosmethyl surface residues on raw apples. Residue levels
were examined only after processing of the postharvest wash treated apples into
applesauce (peeled and unpeeled), apple juice, and apple slices. Thus, the residues
encountered in the following sections will reflect the effect of postharvest wash treatments
and processing.

a. Effect of Postharvest Wash pH at 21'C

Figures 9-12 compare a pH 7 wash to a pH 11 wash, both at 21°C. Figure 9, peeled
applesauce, showed a reduction in azinphosmethyl residue in the pH 11 wash over the
pH 7 wash during the 1993 data year. This was observed for both the 5 minute and the 15
minute wash treatments.

Figure 10, unpeeled applesauce, shows the pH 11 wash for 5 minutes to be more

efl‘ective than a pH 7 wash during 1993. The 15 minute wash was found to be more

57

 

 

Azlnphomlethyl Residue
("919)

 

 

 

 

Azinphoanethyl Residue
("919)

pH=7 pH=1 1
Postharvest Wash pll

    

 

 

1995 Residue Data

Azinphounethyl Residue
Innis)

pH=7 pH=11
Postharvest Wash pll

“-

 

 

 

Figure 9: Effect of Postharvest Wash pH on the Removal of
Azinphosmethyl at 21°C in Peeled Applesauce

58

 

Azinphoanethyl Reddue
(0910)

 

pH=7 pH=1 1
Poathtved Wadi pll

 

\r

 

 

  
 

Azlnphounethyl Residue

 

 

 

I”

 

Azinpholnethyl Reeldue

pH=7 pH=11
Postharvest Wuh pH

 

 

 

 

Figure 10: Effect of Postharvest Wash pH on the Removal of
Azinphosmethyl at 21 °C in Unpeeled Applesauce

59

 

Azinphocnethyl Residue
("919)

pH=7 pH=11
Posthtvest Wash pH

 

 

 

 

 

 

 

Azlnphounethyl Residue

 

 

 

 

 

     

I5 minute
i I 15 minute

Azlnphounethyl Residue
("919)

pH=7 pH=1 1
Postharvest Wash pH

 

 

 

Figure 11: Effect of Postharvest Wash pH on the Removal of

Azinphosmethyl at 21°C in Apple Juice

60

 

AzInphoanethyl Residue
(0919)

 

pH=7 pH=1 1
Pom Wadi pH

.. a “A
v". nu- v

 

 

1994 Residue Data

Aztnphoanethyl Residue

 

 

 

 

 

 

BS minute
I15

8

'e

2

z

E a.

1%

pH=7 pH=11

 

 

Posthuvest Wash pll

“-

 

Figure 12: Effect of Postharvest Wash pH on the Removal of
Azinphosmethyl at 21°C in Apple Slices

61

effective in residue removal than the 5 minute wash at pH 7 in 1993. Data for 1995
showed the 15 minute, pH 11 wash to be more effective than the pH 7, 5 minute wash.

Apple juice data, Figure 11, showed a pH 11, 15 minute wash gave greater residue
removal than the pH 7, 5 minute wash during 1994. A longer wash time was found to be
more effective in the pH 7 wash for 1994. Data for 1995 indicated pH 11 was more
effective than pH 7 during the 5 minute wash.

In apple slices, Figure 12, the pH 11, 15 minute wash was formd to be more capable of
removing residues over pH 7, 5 minute wash as observed during 1993 and 1995. The pH
11 wash was found more efl‘ective than the pH 7 wash during the 1993, 5 minute wash.
The increased effectiveness of a longer wash time showed up during the 1993, pH 11
wash.

In each of the four apple products, there were a number of instances in which the pH
11 wash and a 15 minute wash time were observed to be statistically more effective in
reducing azinphosmethyl residues than the pH 7 wash for 5 minutes. These observations
are in agreement with various studies on the behavior of azinphosmethyl in aqueous
solutions which includes work by Ong et al. (1995) and Faust and Gomma (1972).

b. Effect of Postharvest Wash pH at 43'C

The effects of a pH 7 and pH 11 wash are illustrated in Figures 13-16. In Figure 13,
peeled applesauce, no statistical differences between treatments was observed during all
three years. No determinations could be made concerning pH or wash time variables.

Figure 14, unpeeled applesauce, indicated the pH 11, 15 minute wash to be more
effective at reducing azinphosmethyl residues when compared to the pH 7, 5 minute wash

in the1995 data.

62

 

 

Azinphounethyl Residue
(“919)

 

 

 

 

Azinphounethyl Residue
10919)

Postharvest Wash pH

 

 

 

 

. .1995 39.3”“? Data.

Azinphoanethyl Residue
(09’s)

 

 

 

 

Figure 13: Effect of Postharvest Wash pH on the Removal
of Azinphosmethyl at 43°C in Peeled Applesauce

63

 

Azlnphocnethyl Residue
(“919)

 

 

 

 

Azinphounethyl Residue
(“919)

 

pH 7 pH 11
Postha'vest Wash pH

 

Azlnphoanethyl Residue
Inelei

 

 

 

Figure 14: Effect of Postharvest Wash pH on the Removal
of Azinphosmethyl at 43°C in Unpeeled Applesauce

 

 

 

Azinphounethyl
Residue (uglg)

 

 

 

 

Azinphounethyl Residue
(“919)

 

 

 

 

.5 minus
I15

Azinphounethyl Residue
("9’91

 

pH 7 pH 11
Postharvest Wash pH

 

 

Figure 15: Effect of Postharvest Wash pH on the Removal
of Azinphosmethyl at 43°C in Apple Juice

 

 

65

 

Azlnphounethyl
Readue IugIgI

 

 

 

 

 

 

 

 

 

S
i

'5. A

i

3

pH 7 pH 11
Postharvest Wash pll
.. (1995 Residue Data ISmIanI

 
 

I 15 minute

   

Azinpho-nethyl Residue
("9'91

PH 7 pH 11
Postharvest Wash pil

 

 

Figure 16: Effect of Postharvest Wash pH on the Removal
of Azinphosmethyl at 43°C in Apple Slices

66

Data for 1993 apple juice, Figure 15, showed. the 15 minute wash to be more efl‘ective
over 5 minute wash during the pH 11 treatment. Also during 1993, the pH 7, 15 minute
wash was shown to be statistically more effective than the pH 11, 5 minute wash, at
removing azinphosmethyl residues.

Apple slice data, Figure 16, showed the same lack of statistical distinction between
treatments as that observed in Figure 13. No determinations as to the effectiveness of the
wash treatment variables could be made.

Data from unpeeled applesauce and apple juice indicated a longer wash time and the
pH 11 wash to be more effective at residue removal The observations, though minor, are
in agreement with previous studies by Flint et al. ( 1970), Ong et al. (1995), and Faust and
Gomma (1972).

c. Effect of Postharvest Wash Temperature at pH 7

The effects of 21° C and 43°C wash temperature at pH 7 are illustrated in Figures 17-
20. From Figure 17, peeled applesauce, only one statistically significant observation was
made. Data for 1993, 15 minute wash samples showed a higher temperature (43°C) to be
more effective in removing azinphosmethyl residues.

The 15 minute wash for unpeeled applesauce, Figure 18, removed more residues than
the 5 minute wash during 1993, 21°C treatment. During 1993 and 1995, the 43°C wash
was more efl‘ective at residue removal when compare to the 21°C, 5 minute wash.

Figure 19, apple juice, displayed the longer wash time as being more adequate at
reducing residues in the 1994, 21°C wash. Residue levels were formd to be significantly,

lower in 43°C, 15 minute wash when compared to the 21°C, 5 and 15 minute wash for.

67

 

Aunphoanethyl Residue
(vale)

 

 

 

 

 
 

 

8

2

53

E?

i

3 ...........
21C QC

Postharvest Wash Tun psratwe

 

\r

 

 

 

I5 minute 1
I 15 minute

 

W

Azinphounethyl
Residue (0949)

    

21 C 43 C
Postharvest Wash Temperature

—Iew w— v.

 

Figure 17: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 7 in Peeled Applesauce

 

68

 

    

 

 

 

 

3
1:
2
r:
3. ._
i 5
2
e‘
21 C (3 c
Podharvest Wash Tunperatu'e
1994 Residue Data
3
i
a:
a ._
i
21 C 43 C

Postharvest Wash Tan perahre

- \r

 

 

 

 

 

3
3
g
E
0
2
E
21 C 430

Postharvest Wash Turpentine

 

Figure 18: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 7 in Unpeeled Applesauce

 

69

 

 

Azinphosnethyi Residue
(Halal

 

 

 

 

 

3

i

E-

is“

E-

E

3

21c 48c

Podhl'veat Wash Tunpcatu'e

 

 

 

 

    

i
E
3‘53
"’ 8’
E" ................
E
21 c cc

 

Postharvest Wash Temperature

u-

 

Figure 19: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 7 in Apple Juice

 

70

 

Azinpho-nethyl Residue

 

 

 

 

 

 

1

$3

is

s . .
210 (BC

Postharvest Wash Tunperattre

v \r

 

 

 

 

1995 Residue Data

    

3

i

a:

3...

€— 8

i“

i

N

< ..

21 C QC

Postharvest Wash Tun persttn

 

‘r

 

Figure 20: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 7 in Apple Slices

 

71

1993. Data for 1994 showed residues from the 43°C, 5 and 15 minute wash to be lower
than that observed for the 21°C, 5 minute wash.

The higher temperature wash was more successful in residue removal in the 5 minute
wash treatment for 1993 apple slices, Figure 20. Data for 1994 and 1995 showed no
statistical differences between wash treatments.

Observations relating to the increased capacity of a 43°C wash to remove
azinphosmethyl were noted for all four products. The increased efl'ect of wash time on
reducing residues was observed only once with any statistical significance.

(1. Effect of Postharvest Wash Temperature at pH 11

Figures 21-24 depict the consequences of wash temperature (21°C vs 43°C) at pH 11,
on azinphosmethyl residues. Figure 21 and 22, which illustrate data for peeled and
unpeeled applesauce, respectively, did not offer any statistical differentiation between
wash treatment means.

Figure 23, 1993 apple juice, showed the 43°C, 15 minute wash to be statistically more
effective in reducing azinphosmethyl residues compard to the 21°C, 5 and 15 minute wash.
A longer wash time was shown to be more effective in the 43°C wash.

Apple slices, Figure 24, showed an increase in residue reduction for the 43°C, 5 minute
wash when compared to the 21°C, 5 minute wash during the 1994 data year. Data for
1993 exhibited a longer wash time to be more eflective in the 21°C wash and also found
the 43°C, 5 minute wash to increase residue reduction over the 21°C, 15 minute wash.

Apple juice and apple slices revealed the increased effectiveness of a longer wash time
and a higher wash temperature at removing azinphosmethyl residues. These observations

are in agreement with data by Liang and Lichtenstein (1972) and Ong et al. (1995).

72

 

Azlnphounethyl Residue
Iuslsl

 

21 C 43 c
Posthtved Wash Tunperattte

 

 

5 minme
15 minute

    

 

 

i

‘é- ...................

Eé

i ., _, ..
210 430

Postha'vest Wash Tunperattre

- w

 

 

 

 

Azinphounethyl Residue

 

 

v—uvv ww- _ w

 

Figure 21: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 11 in Peeled Applesauce

 

73

 

 

i :
g- .
5 . , .
21 C QC

Posthmest Wash Tunpsratu'e

v—w— mm W

 

 

Annphoanethyl Residue
(unis)

 

 

 

 

 

S
1:
'l
I
a:
3...

at
i 2
g...
e
R

21 C <30
Posthl'vestWashTunperattle

 

\r

 

Figure 22: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 11 in Unpeeled Applesauce

 

74

 

I5 minus i

I 15 minus

 
    

Azinphocnethyl Residue
(We)

21 C 43 C
Poem-vest Wash T-nparatin

run-- we- \r

 

 

 

(“9‘91

  

Azinphounethyl Residue

 

21 C G C
Postharvest Vlhsh T-npsratwe

‘r

 

 

 

 

Azinpho-nethyl Residue
("9'91

 

21 c 430
PostharveatWaah Temperature

v.— u.

 

Figure 23: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 11 in Apple Juice

 

 

75

 

' 5minme
........ I15minue

    

Azinphounethyl Residue
(09191

21c 43c
PodharvdeashTunparature

 

 

 

I 5 minute
I 15 mintte

    

 

 

 

S

i

3....

g D

g2

.fl

9.

3

fl

( ..

210 43c
PostharveatWaahTamperature

 

 

 

    

 

0

3

i

a...

g Bl

'6 s

E-

O

s

a. .....

:

N

< _ g ‘ ,,

21 c 430
PostharvestWash Tunperattre

 

Figure 24: Effect of Postharvest Wash Temperature on the
Removal of Azinphosmethyl at pH 11 in Apple Slices

 

76

e. Effect of 500 ug/g Chlorine in Postharvest Wash

Figures 25-28, ilhrstrate the effects of 500 ug/g chlorine, in a 21°C, pH 7 postharvest
wash, on azinphosmethyl residues. Figure 25, peeled applesauce, indicates that the 5
minute chlorine wash was more efl‘ective in removing residues than the 5 minute, no-
chlorine wash during 1993. Data for 1995 showed the 5 minute, chlorine wash to be more
effective than the 5 and 15 minute, no-chlorine wash. ‘Data for 1995 also showed the 5
minute, chlorine wash as being more efl‘ective in residue removal than the 15 minute,
chlorine wash.

In unpeeled applesauce, Figure 26, data for 1993 showed the 15 minute, chlorine wash
as increasing residue removal over the 5 and 15 minute, no-chlorine wash. The 5 minute,
chlorine wash was found to be more effective than the 5 minute, no-chlorine wash during
1993 and 1995 data years. Data for 1995 also showed the 15 minute, chlorine wash to be
more efl”ective than the 5 minute, no-chlorine wash. The increased effectiveness of a
longer wash time was exhibited during 1993 in both the chlorine and no-chlorine wash
treatments.

Apple juice data for 1993, illustrated in Figure 27, showed the 15 minute, chlorine
wash to be more adequate in the removal of azinphosmethyl residues than both the 5 and
15 minute, no-chlorine washes. A longer wash time was more effective in the 1993,
chlorine wash and also observed in the 1994, no-chlorine wash. Both the 5 and 15 minute,
chlorine washed showed lower residue levels compared to the 5 minute, no-chlorine wash.

No determinations could be made statistically, concerning wash time or chlorine effects

for 1994 or 1995 data in apple slices, Figure 28. Data for 1993 did show the 5 and 15-

77

 

Azlnphocnethyl Residue
("9’01

 

 

 

 

Azinpholnethyl Residue
(We)

 

 

 

 

Azinpho-nethyl Residue
lug!!!)

 

 

 

Figure 25: Effect of 500 ppm Chlorine on the Removal of
Azinphosmethyl at 21 °C and pH 7 in Peeled Applesauce

 

 

 

 

78

 

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mmmmmmmmmmmmm
000000000000000
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mm
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000000000000000
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Saunaséeaoies

 

 

Chlorine

’

Chlorine “Treatment

Chlorine

 

Figure 26: Effect of 500 ppm Chlorine on the Removal of
Azinphosmethyl at 21 °C and pH 7 in Unpeeled Applesauce

 

79

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

     
 
 

   

., 0.140
s :3:
'5 0:110
a: 0.100
— 0.090
"“ 0.080
§ g 0.07
E a 0.080
. :3: '
'5, 01030 -
= 0.020 .
E 0.0 .;
0.000 »
No mpm
Chlorine Chlorine
Chlorine Treatment
1994 Residue Data Is minute
” 1.15 minus
g //"/,1:
' / /
i: / 5
3. - I
g u / .
‘g E:
3
e.
C
R
<
I No anipm
I Chlorine Chlorine
I Chlorine Treatment
I5 minute
I15minute‘
0.140 -.
3 0.130
3 8'33 '
E 02100
— 0.000
E 3 :3: '
E 3 0:060 .
o 0.050
g 0.040 '
a. .
i 0020
No Sappm
Chlorine Chlorine

Chlorine Treatment

 

Figure 27: Effect of 500 ppm Chlorine on the Removal of
Azinphosmethyl at 21°C and pH 7 in Apple Juice

 

 

80

 

 

IugIei

Azlnphounethyl Residue

 

 

 

 

 

I5 minute
15 minute

    

Azinphounethyl Residue
(“919)

 

 

 

 

S
i.
a:
3, ..
a
g e
g- ...........
'R
< . .
No Stnppm
Chlorine Chlorine

Chlorine Trealrnent

- “-

    

 

 

Figure 28: Effect of 500 ppm Chlorine on the Removal of
Azinphosmethyl at 21 °C and pH 7 in Apple Slices

81

minute, chlorine washes to be more effective in residue removal when compared to the 5
minute, no-chlorine wash.

Chlorine exhibited an increased ability to remove azinphosmethyl residues in
comparison to the no-chlorine wash. These statistically significant observations occurred
at least once in all four products. An increase in wash time was formd to be advantageous
in residue removal in both the chlorine and no-chlorine washes for unpeeled applesauce
and apple juice.

f. Effect of 2% SDS in Postharvest Wash

Figures 29-3 2, illustrate the effect of 2% SDS wash on azinphosmethyl residues, in a
21°C, pH 7 postharvest wash. Figure 29, 1993 peeled applesauce, the 15 minute, SDS
wash was shown to increase azinphosmethyl removal over the 5 and 15 minute, no-SDS
wash. The 5 minute SDS wash was found to be more effective that the 5 minute, no- SDS
wash. No statistical distinctions could be made between wash treatments in the 1994 and
1995 data.

Data for 1993 unpeeled applesauce, Figure 30, indicated the 15 minute, SDS wash to
be more efl‘ective than both the 5 and 15 minute, no-SDS wash in the removal of
azinphosmethyl The 5 minute, SDS wash also showed an increased ability to remove
residues over the 5 minute, no-SDS wash during 1993. A longer wash time was shown to
significantly decrease residues during both the no- SDS and SDS washes. In the data for
1995 samples, the 15 minute, SDS wash was more efl‘ective than the 5 minute, no-SDS
wash.

Figure 31, apple juice, showed the 15 minute, SDS wash to be more advantageous _

when it came to removing azinphosmethyl residues in comparison to the 5 minute,

82

 

  

Azinphounethyl Residue
(ugly)

 

No SDS 2% SDS
Swfactant - Sodium Dodecly Sulfate (SDS)

 

 

  

Azinpho-nethyl Residue
("919)

 

No SDS 2% SDS
Sta'factant - Soditm Dodecly Sulfate (SDS)

 

 

 

 

  

Azinphounethyl Residue
Iuslei

 

No SDS 2% SDS
Surfactant - Sodlun Dodecly Sulfate (SDS)

 

Figure 29: Effect of 2% SDS on the Removal of
Azinphosmethyl at 21°C and pH 7 in Peeled Applesauce

 

 

83

 

 

Azinpholnethyl Residue
Iuslei

No SDS 2* SDS
Sll'faclant -Sod|tln Dodecly Stlfata (SDS)

 

 

 

 

1994 R

Azinphocnethyl Residue
Iuslsi

 

No SDS 2% SDS
Swfactant - Sodltlti Dodecly Sulfate (SDS)

 

 

 

  

Azlnphounethyl Residue
("9'91

 

N0 SDS 2% SDS
Su'factant - Sodium Dodecly Sulfate (SDS)

 

 

Figure 30: Effect of 2% SDS on the Removal of
Azinphosmethyl at 21 °C and pH 7 in Unpeeled Applesauce

 

 

  

 

 

 

  

 

 

 

 

i

E

3; .....

E ..

i

‘R

< .
No SDS 2* SDS
Swfactant - Sodlun Dodecly Sulfate (80s).-

................. 1994 R38 ue Data

3

i

E

3 .............................................
No SDS 2% SDS
Surfactant - Sodlun Dodecly Sulfate (sos)

1995 Residue Data

3

i

'5. ..

3

i

i

C

3

 

No SDS 2% SDS
Surfactant - Sodlun Dodecly Sulfate (SDS)

 

 

Figure 31: Effect of 2% SDS on the Removal of
Azinphosmethyl at 21°C and pH 7 in Apple Juice

 

 

 

85

 

 

Azinpho-nethyl Residue
("919)

No SDS 2% SDS
slur-cum - Sodlun Dodecly Sulfate (50s)

 

 

 

    

Azinphoanethyl Residue
("919)

No SDS 2% SDS
Surfactant - Sodiun Dodecly Sulfate (SDS)

 

 

 

 

    

Azinphounethyl Residue
("919)

No SDS 2% SDS
Surfactant - Sodiun Dodecly Sulfate (SDS)

 

Figure 32: Effect of 2% SDS on the Removal of
Azinphosmethyl at 21 °C and pH 7 in Apple Slices

 

86

no-SDS wash. This was observed during 1993 and 1994. The ability of a longer wash
time to increase residue removal was also found in the no-SDS wash during 1994. Data
for 1994 and 1995 both showed the SDS wash to be more effective over the no-SDS wash
during a 5 minute wash time.

Results for apple slice data, Figure 32, point to the SDS wash as having better residue
removal ability over the no- SDS wash for the 1993, 5 minute treatment. As for the
remaining data, no statistical differences were observed among the treatments.

The conclusions drawn fi'om the results above, indicate 2% SDS did aid in the removal
of azinphosmethyl residues when compared to a similar washes without SDS. This was
observed in all four products. A longer wash time was also found to be an advantage in
removing residues for unpeeled applesauce and apple slices. Only a limited amormt of
literature exists on the use of detergents, such as SDS, for the removal of pesticide
residues. Although no studies directly targeted azinphosmethyl or SDS, similar work by
Chin (1991) and Elkins (1989) did report the successful removal of the pesticide,
parathion, fi'om spinach and broccoli with the use of detergents in wash water.

Postharvest Wash Treatment Results. The proceeding sections illustrated the
effectiveness of wash treatment variables, in combination with processing, on reducing
azinphosmethyl residues. The following conclusions were drawn based on the statistically
significant observations which were made. A pH 11 wash was shown to be more efl‘ective
over a pH 7 wash. This was true for both 21°C and 43°C wash temperatures. A 43°C
wash temperature was found to be more efl‘ective over a 21°C wash, which was true for

both the a pH 7 and pH I] wash. The addition of chlorine (500 ug/g) and SDS (2%) .

87

were both shown to be more efl‘ective in removing residue in comparison to plane water
washes. As for wash time, a longer wash was shown to increase the effectiveness of the
wash variables, as well as the individual wash. These findings are in agreement with
previous studies.

The conclusions drawn from the preceeding sections were not formd to be true for all
the products or during each data year. No patterns were found which would point to a
relationship between wash treatment effectiveness and product type. It was however
noted that most of the statistically significant observations were found to have occured in
data from 1993. Upon closer examination of Figures 9-32, 1993 data shows the highest
overall residue levels, followed by 1995 and 1994 data, respectively. Referring back to
Figure 7 and Table 6, this is the same pattern which was observed in the raw apple residue
data prior to processing. Wheather the higher residue levels observed for 1993 increased
wash treatment effectiveness is not known. The wash treatments which appeared to have
the most significant efl‘ect or those which showed the most statistically significant
observations were the chlorine and SDS wash treatments.

(2) Comparison of Postharvest Wash Treatments

Figures 33-44 illustrate the average azinphosmethyl residues observed in each of the six
wash treatments so that they may be compared as to their relative effectiveness in relation
to one another. Upon review of these figures, residue levels between the various wash
treatments were not found to differ to any great extent. Among the four products, only a
small number of cases were observed in which wash treatments difl‘ered statistically but

with no patterns being observed in which to base any conclusions concerning a more .

88

 

 

5 Minute Wash Time

Azinphosmethyl Residue
(unlit)

 

Wash Treatment
Values with the same letter are not aimlieantly fluent (M95)

 

Wash Treatments

 

 

1. 21°C and pH 7 4. 43°C and pH 11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7.2% SDS

15 Minute Wash Time

Azinphosmethyl Residue
(vale)

 

Wash Treatment
Values with the same letter are net aignlieantiy diersnt (M05)

 

Figure 33: Comparison of Postharvest Wash Treatments -
Azinphosmethyl Residue in Peeled Applesauce, 1993 Data

 

 

89

 

 

5 Minute Wash Time

Azinphosmethyl Residue
(villa)

 

Wash Treatment
Values with the same letter are not simlissntiy disrent (p<0.05)

 

Wash Treatments

 

 

1. 21°Cand pH7 4. 43°Cande11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

15 Minute Wash Time

Azinphosmethyl Residue
(us/0)

 

Wash Treatment
Values with the same letter are not simlioantiy flaunt (p<0.05)

 

Figure 34: Comparison of Postharvest Wash Treatments -
Azinphosmethyl Residue in Peeled Applesauce, 1994 Data

 

 

90

 

 

Azinphosmethyl Residue
(us/0)

 

Wash Treatment
Values with the same letter are not signlicsntiy M (M15)

 

Wash Treatments

 

 

1. 21°C and pH 7 4. 43°C and pH 11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

15 Minute Wash Time

Azinphosmethyl Residue
(Ila/a)

 

Wash Treatment
Values with the same letter are not slmlisantiy disrsnt (p<0.05)

 

Figure 35: Comparison of Postharvest Wash Treatments -
Azinphosmethyl Residue in Peeled Applesauce, 1995 Data

 

 

91

 

 

5 Minute Wash Time

Azinphosmethyl Residue
("ti/ti)

 

Wash Treatment
Values \Mlh the same letter are not aimiicantiy arm (“0.05)

 

 

VIEW—M

1. 21°Cande7 4. 43°Cande11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

 

 

15 Minute Wash Time

    

e
3
i
K
E 3
E 3'
n v ......
o
8
1s .....
i
1 2 3 4 5 6
Wash Treatment

Values with the same letter are not signlicsntly distant (NBS)

 

 

Figure 36: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Unpeeled Applesauce, 1993 Data

92

 

 

5 Minute Wash

m ésez: i?‘**f**t‘f:?*‘~* ‘7‘???”“VET“?"5‘1‘*‘i‘i‘i-‘i'i"“‘f'“?T3777???if???“ r " 3:;(if:13:55::“1; *;*i::;;ifi
0.110 .5 f7 if; ' ' ..

a.” 1:. if ' ' ’

0.0-,0 5g}. ; ., .. . .

0.000 ' '

0.0” ., 1'*-'.-.‘TT31‘131‘3.7.‘:-'tvi{:’*'13':i"3'?.‘.3:i:7:1:3:3;3:-":?:':‘:i.-v;;'7:-.,:}:‘:1:1.?:3:1i?:1:‘;?:§Itif‘:~T"":‘::Z‘i-‘A‘;:-.;I;ir?:.‘;:3:31;";.-:A...A:;:1‘7:;'~..‘_.;:-.:._;,;(A .,_.:.;r.;.,:;;
0.080 ;
0.020 . ,
0.010 _ 1
0.”

Azinphosmethyl Residue
(Ila/ti)

 

Wash Treatment
Values with the same letter are not simiieantly M (p<0.05)

 

Wash Treatments
1. 21°Cande7 4. 43°Cande11

2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine

3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

 

15 Mi ute Wash Time

0440 .. . .. . . _ _. . . .
0.130 ’ 1
0.120 .. .. . ., ,. . .. .. .. .. .. . . .
0.110 r ' " ”

0.100 21
0.000 .355: if '1 ‘ I

0.000 f'j‘i'j

om ;~:' ~ 2 ’

0.000 §;a " _ _. _ .. . .
0.050 :5 :pv';:.;;:.;::::;:;»as»; ' “
0.040
0.000
0.020 f
0.010 _.
0.000

_ ___.______._-J

Azinphosmethyl Residue
(vale)

 

Wash Treatment
Values with the same letter are not signlieantiyflferent (p<0.05)

 

 

Figure 37: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Unpeeled Applesauce, 1994 Data

93

 

 

5 Minute Wash Time

Azinphosmethyl Residue
(Hale)

 

 

 

 

Wash Treatment
Wash Treatments
1. 21°C and pH 7 4. 43°C and pH 11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7. 2% SDS

 

 

15 Minute Wash Time

  

Azinphosmethyl Residue
(us/0)

 

Wash Treatment
Values with the same letter are net simlieantiy diatom (p<0.05)

Figure 38: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Unpeeled Applesauce, 1995 Data

 

 

94

 

 

5 Minute Wash Time

Azinphosmethyl Residue
(us/0)

 

Wash Treatment
Valuasvdlhtheaama lsttsrara notsimfleantiyrllarsnt(p¢.05)

 

Wash Treatments

 

 

1. 21°Cand pH7 4. 43°Cande11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

15 Minute Wash Time

Azinphosmethyl Residue
(Ila/a)

 

Wash Treatment
Values Nth the same letter are not aignfieantiy distant (p<0.05)

 

Figure 39: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Apple Juice, 1993 Data

 

 

95

 

 

0.120 :33 . .,

0.110 35:52":15:51:53,._.:§_:;;;;;;53:35;$2:-‘éii37:73-35:29t{1**i.“g-gitié‘:s§s?:::;;-;§1§;39;5ifi;:;;.g.1;:2;2:;;;:-:.:;f:3::-$913:~:t;::-,:.;.;g;1;:-,jjg.I.3433;25:55..55; 22,—g,
0"” {3.31:3531135331 ‘zj."Zi'iziii?:'7‘_i_i'ivSSH-'13;.3;:;I?‘i"%Ii:f~.i.‘ -.,I;_::: 5,123; 5 3,9: 3,, ,4; 3.531;. '_ , , .
0'“ 3:575": .

0.050 1‘: 'f, ‘ '

0.070 #:1131355{211771131141 '5: "7» #593 13:35:53 9:3-~:5I3‘;{:;"“ ;:;.-;*i§‘:. ~i._,,'.*.;:.;,2::~ .:.;_;_'.;::I:' 25.35.. ,ggi-griifui- :; 3 ,3, 3
0.000 :5.

0.050 3;). 541,331] .. , g»

0.040 El:iii-353’giiz5iiii'ljiiieiiiiliizsttij "I ":1. ..: :3:'§.;.3--‘3_‘3j1:._:;_..,Ij..-j,’ I.i,7§::f?;;jlgf;.gg“j"3.2,,1.ggff ,:_'
0.020 .

0.010 ’:

Azinphosmethyl Residue
(little)

 

Wash Trestrnent
ValuaavdththssamelattararanetWydlersnt(p¢.05)

 

Wash Treatments
1. 21°Cande7 4. 43°Cande11

2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine

3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

 

 

0.120 33;; 7'5"
0.110 2'73]; jii_ 3393;?" {j . -.f§,;}~f§.:,».g 3.237,. 133-3 35,3:3 1,, 5:33:31 7 193:3...3', 1":1235
0.000 gig? 11"?" ' ‘ , . i, 3-. ’ - . 5

0.070 ' . -‘ i z
0.000 iizv‘iL’f’Tx; ; 5:,3'5 =:~'- . ' .: I . L 2.2,, '-
0.050 '71- ‘

0.040 .35 “

0.000 g? *Eii'izif' '35-" ' “ '

15 Minute Wash Time

 

Azinphosmethyl Residue
(Halal

0.010

Wash Treatment
Valuaavddi the asrne lattarara notaigilicsntlyrllarant(p<0.05)

 

Figure 40: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Apple Juice, 1994 Data

 

 

96

 

 

5 Minute Wash Time

Azinphosmethyl Residue
(Ila/a)

 

Wash Treatment
Valuesvliththessmslsttsrarsnotsimlicantlycllerant(p<0.05)

 

Wash Treatments
1. 21°Cande7 4. 43°Cande11

2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine

3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

 

 

 

15 Minute Wash Time

0J20 a§¢H¥JmiVfiiffi4flfiwa"'H ,,.,...

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0.100 .222 Effect: 32: 2:56'55.2iée-z':5»:i-ir’étir:is¥-f-;:::;.-:.;f:::~26:

0.0” 3§E§.".:E‘:}?’§j_i:2: 133.7223",ifsfi'ij-iv-viijggg21ft.“E_:_'v"?g-,..Efi_j3-j 1;; f,"'Iggjgb'j}1?I_',_";.si3jfa-:<'-;I11-.%f31:33:23;IEi3;';5§:g-TIE;51§;“:35.51':1]'3:255}:j15§:?:?i':3-’f-‘Qi"43:"{$.15:2”f~'f-,."-E-;j'_'::}:if;
0000 3?§§§533r331ii§3319739933f77fL'CEVfTififfg3flfifiiil23337ILQLK§AEiiififiiiiflhfifi
0020 3?i333???”3353553331357$37757fi755583575353?ViiiiiffihifTifiifiiii3ffif"iffiiifi
0.000 .52: iij;:i:ji;;;:9;'fij"i€;.; 1153:: f1. 532i'f.§.:.5ii'?fi{l- 1:1 2:? ~:a;::;.;: 223:.

0050 3iEififif;i*“u?*;fiflfiifir%132?fi;i¥f¥¥J?fPfiiiflfifxfixfifafifa¥

0040 i§3?3?iLwflfiéréiiifiisisfilimfiri5%7;59v3917fim2135L$3335

0.030 3713133.»;133‘: ’5‘5:155:53{1333:1135};1313:7335.H2325:?{li'thf'iiii‘}3§§:.'§?I:1:‘3'5ff}31:f3313331§§§_:1:?3_":A:7:;‘1-:§:. rti}:'2§i:§;3j§;:3;}"3jigl133T'i.2333‘33;§;1i325‘5:' '332jfgég‘;

0.000 1.3; :5: ' ‘ " ' '

0.010 g. 5

0.000

Azinphosmethyl Residue
("s/0)

 

Wash Treatment
\hflussvddrdnrsanuiknuwruerunuugnlkandydlkwenturleS)

 

Figure 41: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Apple Juice, 1995 Data

 

 

97

 

 

Azinphosmethyl Residue
(Ila/0)

 

Wash Treatment
Values with the same letter are not almfieantiy distant (p<005)

 

 

Wash Treatments

1. 21°Cande7 4. 43°Cand pH11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS

 

 

. 15101an “Tim..-

Azinphosmethyl Residue
(Ila/til

 

Wash Treatment
Values with the same letter are not simllieantiy diferent (p<005)

 

 

Figure 42: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Apple Slices, 1993 Data

98

 

 

5 Minute Wash Time

    

 

 

 

 

 

 

 

I
3
E
.i
§§
3
n V
0
0:
a.
.E
2
1 2 3 4 5 8
Wash Treatment
Valuasvrtththasamelsttararenotsimliesnttydfsrsnt(p<005)
Wash Treatments
1. 21°C and pH7 4. 43°Cande11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7. 2% SDS
15 Minute Wash Time
I
3
I!
8
0:
3 a
3 a
E E.
8
I:
I.
i

 

Wash Treatment
Values vdth the same letter are not slmlieantiy diarent (p<o05)

Figure 43: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Apple Slices, 1994 Data

 

 

99

 

 

5 Minute Wash Time

Azinphosmethyl Residue
(Hale)

 

Wash Treatment
Values Nth the same letter are not aimlleantly d‘farent (p<0.05)

 

 

 

 

 

Wash Treatments
1. 21°C and pH7 4. 43°C and pH11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7, 2% SDS
15 Minute Wash Time

Azinphosmethyl Residue
("ti/0)

 

Wash Treatment
Values with the same letter are not aimfiosntly different (p<005)

 

 

Figure 44: Comparison of Postharvest Wash Treatments
Azinphosmethyl Residue in Apple Slices, 1995 Data

100

effective wash treatment(s). It was determined that none of the wash treatments showed a
great deal of efl‘ectiveness over another in the removal of azinphosmethyl residues. This
was found to be consistent during all three years of the study and for all products.

(3) Comparison of Raw Apple and Processed Apple Residues

The percent reduction in azinphosmethyl residues in peeled applesauce, Impeeled
applesauce, apple juice, and apple slices are illustrated in Figures 4548, respectively. To
determine the percent residue reduction, raw apple residues (Table 6) were compared to
residues found in each of the four apple products. For each apple product, the residues
determined in the postharvest wash samples (Appendices 4-7) were averaged to yield
values for both the 5 and 15 minute wash treatments for each year of the study. These
average residue levels and those obtained for raw apples are listed in Table 8 and
compared on a one to one basis to obtain a percent reduction in azinphosmethyl residues
resulting from postharvest washing and processing.

From Table 8, similar observations can be made for all four apple products. The
residue levels in raw apples were at their highest during 1993, followed by 1995 and 1994,
respectively. This same residue pattern was observed for all four products, following
postharvest washing and processing. Residue loss was lowest during 1993, followed by
1995 and 1994, respectively. This showed the percent reduction in azinphosmethyl to
decrease in relation to a higher initial residue level in all four products. Despite the
varying degrees of residue reduction observed between years, the high residue losses
resulting from the combination of postharvest wash treatments and processing are very

significant. Peeled applesauce indicated losses from 93.7-96.5% over the three year study.

101

 

 

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inphosmethyl

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104

Unpeeled applesauce, apple juice, and apple slices showed similarly high residue
reduction, 84.2-97.4%, 88.1-100%, and 88.9-97.0%, respectively. These findings are in
agreement with previous studies by El-Hadidi (1993 ), Ong et a1. (1995), Gunther et al.
(1963), and Carlin et al. (1966) on the ability of washing and processing to significantly
reduce azinphosmethyl residues in apples as well as other fi'uits and vegetables.

Figures 45 and 48, peeled applesauce and apple slices, respectively, both showed a
longer wash time to significantly increase residue reduction in 1993 samples. Unpeeled
applesauce, Figure 46, showed a significant reduction in residue, due to a longer wash
time, during 1993 and 1995. Apple juice, Figure 47, did not indicate wash time to be a
statistically significant factor in the reduction of azinphosmethyl residues.

(4) Comparison of Residue Levels between Products

Figure 49 compares the different residue levels found among the four apple products.
The mean residue levels for the six postharvest wash treatments (Tables 4-7) were
combined to give an average azinphosmethyl residue observed for each of the four apple
products. The differences observed in the residue levels between products is a direct
result of the different processing methods used.

Figure 49 shows the residue patterns among the four products differs fiom year to
year. Residue levels were the highest during 1993 and also showed the most dramatic
differences in residue levels between products. During 1993, peeled applesauce showed
the lowest residues and unpeeled applesauce the highest. The difi‘erences in residues
observed between the two applesauces is a result of peeling. Azinphosmethyl is a surface

applied pesticide which is known to have an afinity for the cuticle waxes found on the.

105

 

 

   

1993 Data

5 minute
wash
15 minus

 
       

Azinphosmethyl Residue
("II/a)

Unpeeled Juice Slices
Apple Product

Peeled

 

 

 

1 994 Data

   

   

Azinphosmethyl Residue
("o/I)

  

Unpeeled Juice Slices
Apple Product

Peeled

 

 

 

1995 Data

Azinphosmethyl Residue
(Ila/9)

 

Peeled Unpeeled Juice Slices
Apple Product

 

Figure 49: Comparison of Azinphosmethyl Residues
in Apple Products

 

 

 

106

surface of an apple. When removing the peel you are also removing any residue which
may bound to it. The observed results of peeling are in agreement with studies by El-
Hadidi (1993) and Carlin et al. (1966) which indicate peeling to remove considerable
amounts of residue not removed by washing treatments.

Residue levels were shown to differ significantly between peeled applesauce and apple
slices. The processing of both samples involved peeling but only applesauce involved heat
processing (blanching). The difi‘erences observed among these products is likely a result

of the degradative efi‘ects of heat on azinphosmethyl residues.

1). Captan Residue Study

The following sections will discuss residue studies which were set up to examine the
efl‘ects of individual postharvest wash treatments and their ability to reduce or eliminate
captan residues from finished apple products. The raw data pertaining to captan residues
in peeled applesauce, unpeeled applesauce, apple juice, and apple slices is contained in
Appendices 8, 9, 10, and 11, respectively. This data is illustrated in Figures 50-67. Only
those findings which were calculated to be statistically significant will be discussed.

The following section contains no Figures illustrating the results of captan residue
studies in peeled or impeeled applesauce. Analysis of both types of applesauce samples
indicated captan residues to be absent or below the method detection limit of 0.02 ug/g.
The presence of captan residues in both apple juice and apple slices points to the
processing step of blanching as being responsible for the lack of residues in applesauce. In

the preparation of applesauce, apples are sliced and then blanched for a period often _

107

minutes before they are passed through a finisher and made into sauce. It has been
concluded that the thermal processing step of blanching is responsible for the absence of
captan residues. A number of previous publications are in agreement and indicate captans
instability in the presence of heat. Work by Klayder (1963 ), Elkins et al. (1972), and
Koivistoinen et al. (1965) indicate heat processing, such as canning, cooking, or
blanching, are responsible for 90-100% losses of captan residues in fruits and vegetables.
(1) Effect of Postharvest Wash Treatment Variables
Postharvest wash treatment variables are examined for their efi‘ect on the removal or
degradation of captan surface residues on raw apples. Residue levels were examined only
after processing of the
postharvest wash treated apples into applesauce (peeled and unpeeled), apple juice, and
apple slices. Thus, the residues encormtered in the following sections will reflect the effect
of postharvest wash treatments and processing.

a. Effect of Postharvest Wash pH at 21'C

Figure 50 and 51 illustrate the efi‘ect of wash pH on Captan residues in a 21°C
postharvest wash. Data for 1993 apple juice, Figure 50, showed pH 11, 5 minute wash to
be more effective in removing captan compared to the pH 7, 5 minute treatment. The pH
1 1, 5 minute wash was found to be more effective over the pH 7, 15 minute wash. Also
for 1993, a longer wash time indicated higher residue removal during the pH 7 wash.
Data for 1994 and 1995 did not show any statistical difi‘erentiation in sample means.

Apple slice data, Figure 5], exhibited pH11 to be more capable of captan removal over

the pH 7 wash. This was observed for 1993 and 1995 data during the 15 minute wash. A

108

 

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Figure 50: Effect of Postharvest Wash pH on the Removal
of Captan at 21 °C in Apple Juice

 

109

 

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Figure 51: Effect of Postharvest Wash pH on the Removal
of Captan at 21°C in Apple Slices

 

no

longer wash time also appeared to be more effective in the 1993, pH 11 wash. The
opposite however was observed during the 1995, pH 7 wash. In this case, a 5 minute
wash time was found to be more efi‘ective, over the 15 minute wash, at removing captan
residues. Data for 1995 also showed the pH 11, 15 minute wash to be more effective than
the pH 7, 5 minute wash.

In both apple juice and apple slice studies, the pH 11 wash proved to be statistically
more effective in reducing captan residues. A longer wash time was also found to be more
effective for both products. This data is in agreement with previous studies by Ong et al.
(1995) and Wolf et al. (1976) on captan residues in sohition. The observation (Figure 51,
1995 data) in which the 5 minute wash was found to be more effective, over the 15 minute
wash, can not be explained and is not agreement with previous data.

b. Effect of Postharvest Wash pH at 43'C

Figure 52 and 53 illustrate the effect of pH on captan residues in a 43°C wash. Apple
juice data, Figure 52, indicated a longer wash time as more capable of removing captan
residues in both the pH 7 and pH 11 treatments during 1993. The pH 11, 15 minute wash
was also shown to be more effective than the pH 7, 5 minute wash, as observed in the
1993 data.

Figure 53, apple slices, did show a higher pH to be more efi‘ective in reducing captan
residues during 1995. This was found when comparing the pH 11, 15 minute wash to the
pH 7, 5 minute wash. No other statistically significant findings were made.

These observations showed the increased effectiveness of the pH 11 wash and a longer
wash time. This data is in agreement with previous studies by Ong et al. (1995) and .

Wolfe et a1. (1976).

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Removal of Captan at 43°C in Apple Juice

 

112

 

1993 Residue Data

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Removal of Captan at 43°C in Apple Slices

 

113

c. Effect of Postharvest Wash Temperature at pH 7

Figure 54 and 55 represent data which illustrates the effect of temperature on captan
residues in pH 7 postharvest wash treatments. Figure 54, apple juice, shows the 5 and 15
minute, 43°C wash to be more capable of removing captan residues when compared to the
5 minute, 21°C wash for 1993 samples. A 15 minute wash time was shown to increase
captan removal over a 5 minute wash in both the 21°C and 43°C temperature treatments.
Data for 1994 and 1995 displayed no further information on wash treatment variables.

Apple slice data for 1993, Figure 55, showed the 43°C, 15 minute wash to further
reduce captan residues when compared to 21°C, 5 and 15 minute washes. Data from 1995
a longer wash time to be more effective in the 21°C wash.

Despite the few statistically significant observations, those that were made did agree
with previous research by Dog et al. (1995). These findings indicated a longer wash time,
as well as a higher temperature, increased the removal of captan residues at pH 7.

(1. Effect of Postharvest Wash Temperature at pH 11

Figures 56 and 57 illustrate the efl‘ect of 21°C and 43°C wash temperature on captan
residues at pH 11. Apple juice data, Figure 56, shows the 15 minute, 43°C wash to
significantly reduce captan residues when compared to both the 5 and 15 minute, 21°C
wash during 1993. Data from 1993 also showed a longer wash time to be more effective
in the 43°C wash. No other statistically significant observations were made for apple juice
or for apple slices, Figure 57.

The statistically significant observations made are in agreement with previous studies
by Ong et al. (1995). A longer wash time and a higher wash temperature were more _

beneficial to the removal of captan residues at pH 11.

114

 

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Removal of Captan at pH 7 in Apple Juice

 

115

 

1993 Residue Data
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116

 

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117

 

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Removal of Captan at pH 11 In Apple Slices

 

118

e. Effect of 500 uglg Chlorine in Postharvest Wash

The efl‘ects of 500 ug/g Chlorine on captan residues in a pH 7 and 21°C postharvest
wash are illustrated in Figures 58 and 59. Figure 58, 1993 apple juice, showed the 15
minute, Chlorine wash to be more effective in lowering captan resides when compared to
the 5 minute, no-chlorine wash. A longer wash time was shown to be more effective in
the 1993, chlorine wash.

Apple slice data, Figure 59, showed the 500 ug/g Chlorine wash to increase the
removal of captan residues over the no-chlorine wash. This was determined to be
statistically significant for both the 5 minute and 15 minute washes during 1993. A longer
wash time was shown to increase residue removal in the no-chlorine wash according to
1995 data.

A longer wash time and the use of Chlorine increased the chance of captan residue
removal Again, we see few observations but those that are made are in agreement with
previous work by Ong et al. (1995).

1’. Effect of 2% Sodium Dodecyl Sulfate in Postharvest Wash

Figures 60 and 61 help to illustrate the raw data examining the difference in captan
residue removal fi'om apples when comparing a 2% SDS wash with a wash lacking SDS.
These postharvest wash treatments had a pH 7 and were at 21°C. For apple Juice, Figure
60, statistically significant observations were only found in the 1993 data. This exhibited
2% SDS to have an increased ability to remove Captan residues over the no-SDS wash.
This was found to be true for both the 5 minute and 15 minute wash treatments. The
longer wash time was also found to increase residue removal in both the 2% SDS and no-

SDS washes for 1993.

119

 

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120

 

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121

 

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Figure 60: Effect of 2% SDS on the Removal of
Captan at 21°C and pH 7 in Apple Juice

 

122

 

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Captan Residue (uglg)

No SDS 2% SDS

 

39..
:<\

 

 

Figure 61: Effect of 2% SDS on the Removal of
Captan at 21 °C and pH 7 In Apple Slices

 

123

Figure 61, apple slices, also found the presence of SDS in the postharvest wash to
increase residue removal during both the 5 and 15 minute washes for 1993. Similarily,
1995 data showed the 5 minute SDS wash to be more efl‘ective in comparison to the 5
minute, no—SDS wash. Data for 1995 also illustrates a longer wash time to be more
adequate at residue removal in the no- SDS wash treatment.

Data for 1993 showed a lot of potential, in both apple juice and apple slice, for SDS to
increase captan residue removal. Both products indicated a longer wash time to be more
advantageous in terms of captan residue removal Captan showed similar susceptibility to
SDS as did azinphosmethyl. No previous data was found which emphasized the use of
SDS for captan residue removal. Studies by Chin (1991) and Elkins (1989), which
reported the use of detergents in wash treatments to increase the removal of a parathion in
vegetables, were in agreement with the results of this study.

Postharvest Wash Treatment Results. The preceeding sections illustrated the
effectiveness of wash treatment variables, in combination with processing, on reducing
captan residues. The following conclusions were drawn based on the statistically
significant observations which were made. A pH 11 wash was shown to be more effective
over a pH 7 wash. This was true for both 21°C and 43°C wash temperatures. A 43°C
wash temperature was found to be more efl"ective over a 21°C wash, which was true for
both the a pH 7 and pH 11 wash. The addition of chlorine (500 ug/g) and SDS (2%)
were both shown to be more efiective in removing residues over a plane water wash. A
longer wash was shown to increase the efl‘ectiveness of the wash variables, as well as the

individual wash. These findings are in agreement with previous studies. The wash

124

treatments were found to have similar effects on both the apple juice and apple slices.
SDS was found to be particularly effective in the removal of captan in both apple juice and
apple slices during 1993.

The absence of captan residues fi'om peeled and unpeeled applesauce was determined
to be a result of heat processing (blanching) and not due to wash treatment variables.
Captan residues in apple juice and apple slices showed a similar susceptibility to the wash
treatment variables as did azinphosmethyl Similar to azinphosmethyl data, captan
residues were higher during 1993 which resulted in the occurance of more statistically
significant observations. Referring back to Figure 8 and Table 6, captan residues in the
raw apples showed a similar pattern as that found in the processed apples. Again, it is
unknown whether the higher captan residue observed for 1993 data may be responsible for
the increased influence of the wash treatments.

(2) Comparison of Postharvest Wash Treatments

Figures 62-67 illustrate the average captan residues observed in each of the six wash
treatments so that they may be compared as to their relative effectiveness in relation to

one another. Upon review of these figures, residue levels between the various wash
treatments were not found to difl‘er to any great extent. Among the four products, only a
small number of cases were observed in which wash treatments difl‘ered statistically but
with no patterns observed in which to base any conchrsions concerning a more efi‘ective
wash treatment( 8).

(3) Comparison of Raw Apple and Processed Apple Residues

The percent reduction in captan residues in peeled applesauce, unpeeled applesauce, apple

juice, and apple slices are illustrated in Figures 68-69, respectively. To determine the

125

 

 

5 Minuu Wash Time

Captan Residue (ugly)

 

Wash Treatment
Values with the same letters are not significantly Gleam (N35)

 

 

 

Wash Treatments
1. 21°Cande7 4. 43°Cande11
2. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine
3. 43°C and pH 7 6. 21°C and pH 7. 2% SDS
15 Minute Wash Time

Captan Residue (ugly)

 

Wash Treatment
Values with the same letters are not my ileum (p<0.05)

 

Figure 62: Comparison of Postharvest Wash Treatments -
Captan Residue in Apple Juice, 1993 Data

 

 

126

 

 

5 Minute Wash Time

Captan Residue (ugly)

 

Wash Treatment
Values with the same lettere are not simiieently m (p<0.05)

 

Wash Treatments
1. 21°Cande7 4. 43°Cande11

N

. 21°C and pH 11 5. 21°C and pH 7, 500 ppm Chlorine

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Valuee with the same letters are not eimlieently alerent (p<0.05)

 

Figure 63: Comparison of Postharvest Wash Treatments -
Captan Residue in Apple Juice, 1994 Data

 

 

127

 

 

5 Minute Wash Time

Captan Residue (ugly)

 

Wash Treatment
Values with the same letters are not eimfleentlycll‘erent (p<0.05)

 

Wash Treatments
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Figure 64: Comparison of Postharvest Wash Treatments -
Captan Residue in Apple Juice, 1995 Data

 

 

128

 

 

 

 

 

 

 

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Values with the same letters are not signfleantly diluent (p<0.05)

 

Figure 65: Comparison of Postharvest Wash Treatments -
Captan Residue in Apple Juice, 1993 Data

 

 

129

 

 

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Captan Residue in Apple Juice, 1994 Data

 

 

130

 

 

 

 

 

 

    

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Figure 67 Comparison of Postharvest Wash Treatments -
Captan Residue in Apple Juice, 1995 Data

 

 

131

 

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Percent Reduc

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F

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Year of Study

 

 

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Percent Reduc

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69

Figure

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132

percent residue reduction, raw apple residues (Table 6) were compared to residues found
in each of the four apple products. For each apple product, the residues determined in the
postharvest wash samples (Appendices 8-11) were averaged to yield values for both the 5
and 15 minute wash treatments during each year of the study. These average residue
levels and those obtained for raw apples are listed in Table 9 and compared on a one to
one basis to obtain a percent reduction in azinphosmethyl residues resulting from
postharvest washing and processing.

Table 9 indicates similar residue patterns in both the raw and processed apples (juice
and slices) as that observed for azinphosmethyl. Residue levels in raw apples were at their
highest during 1993, followed by 1995 and 1994, respectively. This same residue pattern
was observed for apple juice and apple slices, following postharvest washing and
processing. The percent reduction in captan was shown to decrease in relation to higher
initial residue levels. Residue loss was lowest during 1993, followed by 1995 and 1994,'
respectively. Peeled and unpeeled applesauce samples showed captan residue losses of a
100% in all treatments and during all three years of the study. Apple juice and apple slice
data also showed large reductions in residues, Figure 68 and 69, respectively. Apple juice
and apple shoes showed percent reductions of 87.9-100% and 92.8-98.9%, respectively.
Overall, high reductions in captan residues were observed in all products from the
combination of postharvest wash treatments and processing. These findings are in
agreement with previous studies by Ong et al. (1995), Koivistoinen et al ( 1965), Frank et
al. (1983), and El-Zemaity (1988) on the ability of washing and processing to significantly

reduce captan residues in apples as well as other fruits and vegetables.

133

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Figures 68, apple juice, showed a longer wash time to significantly increase residue
reduction in 1993 samples. Apple slices, Figure 69, did not indicate wash time to be a
statistically significant factor in the reduction of azinphosmethyl residues.

(4) Comparison of Residue Levels between Products

Figure 70 compares the different residue levels found among the four apple products.
The mean residue levels for the six postharvest wash treatments (Tables 8-11) were
combined to give an average azinphosmethyl residue observed for each of the four apple
products. The differences observed in the residue levels between products is a direct
result of the different processing methods used.

Figure 70 shows the dramatic effects of the heat processing step (blanching) on captan
residues in both the peeled and unpeeled applesauce. Residue levels observed for apple

juice and apple slices were not found to be significantly different.

135

 

    

 

 

 

 

 

 

 

1993 Data

3

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Apple Product
1994 Data

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Apple Product
1995 Data

g

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Peeled Unpeeled Juice Slices
Apple Product

 

Figure 70: Comparison of Captan Residues
in Apple Products

 

 

SUNIMARY AND CONCLUSIONS

The objective of this study was to examine the effectiveness of preharvest intervals
(PHI), postharvest wash treatments, and processing on pesticide residues in raw and
processed apple fiuits. This study was conducted over a three year period.

To study the effects of preharvest intervals, final spray treatments were altered to yield
apples with PHI’s of 7, l4, and 21 days. Examination of the raw (unwashed and
improcessed) PHI treated apples revealed residue patterns inconsistent with those
observed in previous studies. Data for 1993 and 1995 showed residue levels, for both
azinphosmethyl and captan, to be at their highest in the 14 day PHI samples, followed
respectively by 7 day and 21 day samples. Data for 1994 indicated azinphosmethyl and
captan to be highest in the 7 day PHI samples, followed by 14 day and 21 day samples,
respectively. Previous studies have shown residues of both pesticides to decrease with an
increase in PHI. This was observed in the 1994 data only.

A possible explanation for the residue patterns observed for 1993 and 1995 data point
to the spray treatment. In the field, 14 day PHI samples were located directly between
both the 7 and 21 day PHI samples, with only on buffer row separating each treatment.
The close vicinity of the treatment rows, particularly the 14 day PHI treatment, creates a
lot of potential for problems resulting from spray drift. This would help to explain the.

residue pattern observed for both pesticides during the 1993 and 1995 data years.

136

137

Previous field studies indicate rainfall to be efi‘ective in the removal of both captan and
azinphosmethyl from apple fruit, particularly when closely following a spray application.
Rainfall was recorded shortly following application of the 14 day final spray in 1994. This
would most likely resulted in lower than expected residue levels for the 14 day PHI
samples. Thus, it is the combination of rainfall and spray drifi which help to explain the
residue patterns of both pesticides observed in 1994 data.

Residues were also found to vary significantly from year to year for both pesticides,
with 1993 being the highest, followed by 1995 and 1994, respectively. The reason for
variations in residue levels from year to year can not be explained This is most likely a
direct result of the difi‘erent climatic conditions which are encountered from year to year.
Due to the unexpected results encountered during the PHI study the effect of PHI on
postharvest washed and processed apple samples was not discussed.

Raw apples sprayed with both pesticides were used to determine the efi‘ectiveness of
postharvest washing and processing on the removal of the pesticides in apple products.
Postharvest wash treatments included: (1) 21° C and pH 7; (2) 21° C and pH 11; (3) 43°
C and pH 7; (4) 43° C and pH11; (5) 21° C and pH 7, 500 ug/g Chlorine; (6) 21° C and
pH 7, 2% Sodium Dodecyl Sulfate (SDS). Following postharvest wash treatment, apples
were processed into peeled applesauce, unpeeled applesauce, apple juice, and apple shoes.
Examination'of the statistically significant observations, from the postharvest washed and
processed apple samples, revealed similar findings for both pesticides, excluding captan
applesauce (peeled and unpeeled) samples. A pH 11 wash was shown to be more

efi'ective in reducing residues over a pH 7 wash. This was true for both 21° C and 43°C

138

wash temperatures. A 43° C wash temperature was formd to be more effective over a
21°C wash, which was true for both a pH 7 and pH 11 wash. Chlorine (500 jig/g) and
SDS (2%) were both shown to be more effective in removing residues over plain water
washes. A longer wash time was found to increase the efi‘ectiveness of the wash variables,
as well as the individual wash. These findings were not found consistently for any of the
apple products or during any year of the study. Data for 1993, which had the highest
initial residues prior to postharvest washing and processing, showed the largest number of
statistically significant observations.

Examination of peeled and unpeeled applesauce for captan revealed no detectable
residues. The absence of captan residues was concluded to be a result of the blanching
step involved in the processing of both applesauce types. Previous works have indicated
captans high susceptibility to heat. This fact, combined with the presence of captan in
both apple juice and apple slice samples, point towards the processing as being the limiting
factor responsible for its removal from applesauce samples.

Comparing the effects of the six postharvest wash treatments to one another, revealed
no significant observations. No one particular wash treatment was identified as having
more potential for reducing residue levels. This was found to be true for both
azinphosmethyl and captan residue studies.

The percent reductions in azinphosmethyl and captan residues were examined by
comparing residues found in the raw apple with the preharvest washed and processed
apple samples. Azinphosmethyl and captan residue losses resulting from postharvest
washing and processing were significant for both pesticides and in all products.

Azinphosmethyl losses in peeled applesauce, unpeeled applesauce, apple juice, and apple

139

shoes were between 93.7-96.5%, 84.2-97.4%, 88.1-100%, and 88.9—97.0%, respectively.
Captan losses in peeled applesauce, unp eeled applesauce, apple juice, and apple shoes
were 100%, 100%, 87.9—100%, and 92.8-98.9%, respectively. The lowest residue losses
for both pesticides were observed during 1993 in all products, with the highest losses
observed during 1994 and 1995, respectively. Residues for both pesticides were found to
the highest in the raw apple samples during 1993, followed by 1995 and 1994,
respectively. Thus, higher percent reductions for both pesticides were achieved in relation
to the lower initial residues found in the raw apples samples.

To conclude, well regulated spray treatments with the implementation of appropriate
PHIs can be used to lower residue levels observed at harvest. This, combined with
postharvest wash treatments and processing can greatly reduce or ehminate pesticide

residues.

FUTURE WORK

Possible future research efi‘orts include:

1. This study looked at the combined effects of postharvest wash treatments and
processing on the removal of azinphosmethyl and captan residues in apple products. This
study was not able to distinguish between the efi‘ects of the wash treatments and
processing on residue levels. Future work should include analysis of the residue levels

following both the wash and processing steps.

2. The use of detergents, such as SDS, to aid in the removal of pesticide residues has not
been explored to a large extent. This study indicated SDS have some potential in
postharvest wash treatments for the removal of pesticide residues. More research should
be carried out to further investigate SDS and the concentrations which may be used to

maximize reductions of pesticide residue levels.

3. Future work should include a look at the degradative pathways of these two

pesticides during postharvest washing and processing. Assessment of toxicity should also

be carried out on the degradation products.

140

APPENDICES

142

Appendix 2: A Typical Standard Curve For
Azinphosmethyl Standards

 

 

 

 

 

 

 

o 0.5 1 1.5 2 2.5 3 3.5 4
Concentration (uglg)

 

 

 

143

Appendix 3: A Typical Standard Curve For Captan

Standards

 

 

 

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BIBLIOGRAPHY

BIBLIOGRAPHY

Aizawa, H. 1982. Metabolic Maps of Pesticides, F. Coulston and F. Korte (Ed.).
Acedemic Press, Inc., Tokyo.

Aspelin, AL. and Ballard, G.L. 1980. Pesiticide industry sales and usage: 1980 market
estimates. Washington, DC, Economic Analysis Bureau, Environmental Protection

Agency.

Beall, G.A, Brulm, C.M., Craigmill, AL. and Winter, C. 1991. Pesticides and your
food: How safe is “safe”? California Agriculture 45(4): 4-11.

Belanger, A., Bostanian, N.J., Boivin, G. and Boudreau, F. 1991. Azinophosmethyl
residues in apples and spatial distribution of fluorescien in Vase-shaped apple trees. J.
Environ. Sci Health 62: 279-291.

Braude, G.L. and Wade, MJ. 1983. Water chlorination and foods - FDA considerations
and concerns. Ch. 104 in Water Chlorination - Environmental Impact and Health
Eflects, Vol. 4, Book 2. Ann Arbor Science, Ann Arbor, MI.

Buyanovsky, G.A, Pieczonka, G.J., Wagner, GR and Fairchild, ML. 1988.
Degradation of captan under laboratory conditions. Bull Environ. Contam. Toxicol 40:
689-695.

Carlin, A. F., Hibbs, ET. and Dahm, PA. 1966. Insecticide residues and sensory
evaluation of canned and frozen snap beans field sprayed with Guthion and DDT. Food
Technol. 20(1): 80-83.

Chemagro Division Research Stafl‘ 1974. Guthion® (azinphosmethyl): Organophos-
phorus insecticide. Residue Reviews 51: 125-148.

Chin, HB. 1991. The effect of processing on residues in foods. Ch. 19 in Pesticide
Residues and Food Safety, B.G. Tweedy, HJ. Dishburger, L. G. Ballantine, and J.
McCarthy (Ed. ), p. 175-181. American Chemical Society.

Coats, IR 1991. Pesticide degradation mechanisms and environmental activation. Ch. 2
in Pesticide Transformation Products, L. Somasundaram and IR. Coats (Ed.), p. 10-30.

160

161

Code of Federal Regulations (CFR), USA 1996. Protection of the environment. Chapter
1. Environmental Protection Agency, Titly 40, Pesticide Tolerance / Commodity /
Chemical Index, Federal Register, Washington DC.

Crop Protection Reference 1996. Chemical and Pharmaceutical Press, 12th Edition,
N.Y..

Downing, L.D. (Ed.) 1989. Processed Apple Products. Van Norstrand Reinhold, New
York.

Dychdala, GR. 1977. Chlorine and chlorine compounds. In Disinfection, Sterilization,
and Preservation, 2nd ed., S.S. Block (Ed. ), p. 167-195. Lea and Febiger, Philadelphia,
Pa.

Easter, ER and DeJonge, 1.0. 1985. The eficacy of laundering captan and guthion
contaminated fabrics. Arch. Environ. Contam. Toxicol 14: 281-287.

Ebeling, W. 1963. Analysis of the basic processess involved in the deposition,
degradation, persistence, and effectiveness of pesticides. Residue Reviews 3: 35-147.

El-Hadidi, M.F. 1993. Studies on pesticide residues in fresh and processed apple fruits
under certain developed pest control programs. Ph.D. Dissertation. Department of
Economic Entomology, Faculty of Agriculture, Cario University, Egypt.

Elkins, ER. 1989. Effect of commercial processing on pesticide residues in selected
fruits and vegetables. J. Assoc. Ofl‘. Anal. Chem. 72(3): 533-535.

Elkins, E.R., Farrow, RP. and Kim, ES. 1972. The efl‘ect of heat processing and storage
on pesticide residues in spinach and apricots. J. Agric. Food Chem 20(2): 286-291.

El-Zemaity, MS 1988. Degradation behavior of captan and foplet on greenhouse
tomatoes. Bull Environ. Contam Toxicol 40: 80-85.

El-Zemaity, MS. 1988. Residues of captan and folpet on greenhouse tomatoes with
emphasis on the efl‘ect of storing, washing, and cooking on their removal Bull Environ.
Contam Toxicol. 40: 74-79.

Eto, M. 1974. Organophosphorus Pesticides: Organic and Biological Chemistry. CRC
Press, Cleveland, Ohio.

FAO. 1991. Pesticide residues in food - 1991. FAO Plant Production and Protection
Paper, 113/1.

Faust, SD. and Gomaa, HM. 1972. Chemical hydrolysis of some organic phosphorus
and carbamate pesticides in aquatic environments. Envir. Lett. 3(3): 171-201.

162

Flint, D.R., Church, D.D.,‘ Shaw, HR. and Armour II, J. 15 December 1970. Soil nmofi;
leaching, and adsorption, and water stability studies with Gution. Mobay Report No.
28936.

Frank, R, Braun, HE. and Ripley, B.D. 1989. Monitoring Ontario-grown apples for
pest control chemicals used in their production, 1978-86. Food Addit. Cotam. 6(2): 227-
234.

Frank, R, Braun, HE, Ripley, B.D. and Pitblado, R 1991. Residues of nine insecticides
and two ftmgicides in raw and processed tomatoes. J. Food Prot. 54(1): 41-46.

Frank, R., Braun, HE. and Ritcey, G. 1987. Disappearance of captan from field- and "
greenhouse-grown tomato fruit in relationship to time of harvest and amount of rainfall. .
Can. J. Plant Sci 67: 355-357. ‘

Frank, R., Braun, HE. and Stanek, J. 1983. Removal of captan from treated apples.
Arch. Environ. Contam. Toxicol. 12: 265-269.

Frank, R., Northover, J. and Braun, HE. 1985. Persistance of captan on apples, grapes,
and pears in Ontario, Canada, 1981-1983. J. Agric. Food Chem. 33: 514-518.

Freed, V.H., Chiou, CT. and Schmedding, D.W. 1979. Degradation of selected
organophosphate pesticides in water and soil J. Agric. Food Chem. 27: 706-708.

Geisman, J .R 197 5. Reduction of pesticide residues in food crops by processing.
Residue Reviews 54: 43-54.

Gilvydis, D.M., Walters, S.M., Spivak, ES. and Hedblad, RK 1986. Residues of captan
and folpet in strawberries and grapes. J. Assoc. Ofi‘. Anal. Chem. 69(5): 803-806.

Goring, C. A 1., Laskowski, D.A, Hamaker, J.W. and Meikle, R.W. 1975. Principles of
pesticide degradation in soil In Environmental Dynamics of Pesticides, R. Haque and
V.H. Freed (Ed. ), p. 135-172. Plenum Press, New York.

Grubbs, RE. 1969. Procedures for detecting outlying observations in samples.
Technometrics 1 1(1): 1-21.

Gunther, F.A, Carmen, G.E., Blinn, RC. and Barkley, III 1963. Persistence of residues
of guthion on and in mature lemons and oranges and in laboratory processed citrus “pulp”
cattle feed. J. Agric. Food Chem 11(5): 424-427.

Gunther, F.A, Iwata, Y., Carman, GE, and Smith, CA. 1977. The citrus reentry ‘
problem: research on its causes and efl‘ects, and approaches to its minimization. Residue
Reviews 67: 1-139.

163

Hansen, J.D., Schneider, B.A, Olive, B.M. and Bates, J.J. 1978. Personnel safety and

foliage residue in an orchard spray program using azinphosmethyl and captan. Arch.
Environ. Contam. Toxicol 7: 63-71.

Klayder, T]. 1963. Captan in green vegetables. J. Assoc. OfE Anal. Chem 46(2): 241-
243.

Koivistoinen, P., Karinpaa, A, Kononen, M. and Roine, P. 1965. Magnitude and stability
of captan residues in fresh and preserved plant products J. Agric. Food. Chem 13(5):
468-473.

Liang, T. T. and Lichtenstein, ER 1972. Effect of light, temperature, and pH on the
degradation of azinphosmethyl. J. Econ. Entom 65(2): 315-321.

Liang, T.T. and Lichtenstein, RP. 1976. Effects of soils and leaf surfaces on the
photodecomposition of [”C] azinphosmethyl. J. Agric. Food Chem 24(6): 1205-1210.

Lichtenberg, E. and Zilberman, D. 1986. Problems of pesticide regulation: Health and
environment versus food and fiber. Ch. 4 in Agriculture and the Environment, T.T.
Phipps, RR Crosson, and KA Price (Ed), p. 123-145. Resources for the Future,
Washington, DC.

Liska, BJ. and Stadelman, W.J. 1969. Efi‘ects of processing on pesticides in foods.
Residue Reviews 29: 61-72.

Lombardo, P. 1989. The FDA pesticide program: Goals and new approaches. J. Assoc.
011‘. Anal Chem 72(3): 518-520.

Maybury, RB. 1989. Codex alimentarius approach to pesticide residue standards. J.
Assoc. Ofi‘. Anal Chem 72(3): 538-541.

Northover, J., Frank, R. and Braun, HE. 1986. Dissipation of captan residues from
cherry and peach fi'uits. J. Agric. Food Chem 34: 525-529.

Ong, KC., Cash, J.N., Zabik, M.J., Siddiq, M. and Jones, AL. 1996. Chlorine and
ozone washes for pesticide removal from apples and processed apple sauce. Food
Chemistry 55(2): 153-160.

Petersen, B., Tomerlin, JR and Barraj, L. 1996. Pesticide degradation: Exceptions to
the mle. Food Tech. 50(5): 221-223.

Pimental, D.I. 1976. World food crisis: energy and pests. Bull Entomol Soc. A 22: 20-
26.

164

Rashid, KA, Kawar, N.S., Hull, LA and Mumma, R0. 1987. Residues and
mutagenicity of captan applied to apple trees and potential human exposure. J. Environ.
Sci. Health 22(1): 71-89.

Ricks, D. and Hull, J. 1992. Status and potential of Michigan agriculture - Phase 11:
Tree Fruit. Michigan State University Agricultural Experiment Station Special Report
5 7.

Ritchey, SJ. 1981. Efi‘ects of processing on pesticide residues in food. In Handbook of
Nutritive Value of Processed Food, Vol. 1, Miloslav Rechcigl, Jr. (Ed.), p. 609-614. CRC
Press, Boca Raton, Fla.

Salyani, M. and Cromwell, RP. 1991. Spray drifi from grormd and aerial applications.
ASAE Paper No. 91-1083.

Shibamoto, T. and Bjeldanes, LP. 1993. Introduction to Food Toxicology. Academic
Press, San Diego.

Smith, DP. and MacHardy, W.E. 1984. The retention and redistribution of captan on
apple foliage. Phytopathology 74(8): 894—899.

Suzumoto, R, Ogiso, M. and Tanabe, H. 1983. Efl‘ect of residueal chlorine on the
degradation of pesticides in water. Research Bulletin of the Aichi-ken Agric. Res. Cent.
15: 15 l- 15 5.

USDA 1992. Pesticide data program US. Dept. of Agriculture, Agricultural Marketing
Service (AMS), Washington, DC.

Vettoreazzi, G. 1977 . State of the art of the toxicological evaluation carried out by the
Joint FAQ/WHO Expert Committee on pesiticide residues. [[I. Miscellaneous pesticides
used in agriculture and public health. Residue Reviews 66: 137-182.

Willis, G.H., McDowell, L.L., Southwick, L.M. and Smith, S. 1994. Azinphosmethyl and
fenvalerate washofl‘ from cotton plants as a function of time between application and
intitial rainfall. Arch. Environ. Contam Toxicol 27 : 115-120.

Winterlin, W., Mourer, C. and Bailey, J .B. 1974. Degradation of four organophoshpate
insecticides in grape tissues. Pesticides Monitoring Journal 8(1): 59—65.

Wolfe, N.L., Zepp, RG., Doster, J.C. and Hollis, RC. 1976. Captan Hydrolysis. J.
Agric. Food Chem 24(5): 1041-1045.

Zweig, G. (Ed. ). 1964. Analytical Methods for Pesticides, Plant Growth Regulators, _
and Food Additives. Academic Press, New York

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