Information, knowledge, and demand for substitute health inputs : experimental evidence of pesticide use in Zambia

ABSTRACTINFORMATION, KNOWLEDGE, AND DEMAND FOR SUBSTITUTE HEALTH INPUTS: EXPERIMENTAL EVIDENCE OF PESTICIDE USE IN ZAMBIAByJoseph Christopher GoebMany goods carry health risks that have important impacts on demand and behavior. However, the risks are rarely transparent and, as a result, consumers often have incomplete knowledge of the health risks associated with many of their consumption decisions. This can lead to inefficient behavior. With that in mind, economists have studied the impacts of risk information on consumer behavior, though the effects are rarely straightforward as there may be risk compensation and substitution effects across inputs and behaviors. This dissertation tests the effects of information on knowledge and demand for two substitute health inputs using a randomized control trial of pesticide users in rural Zambia.Essay 1 contributes to the broader literature on information, knowledge, and preventative health demands, and to the pesticide safety literature by presenting the first randomly controlled test of the impacts of pesticide safety information on willingness-to-pay (WTP) for personal protective equipment (PPE) measured using two Becker-DeGroot-Marschak mechanisms. Despite knowledge improvements from the training, overall effects on demand for PPE were insignificant. We also find that demand for both gloves and masks is highly elastic near their market prices.Essay 2 shows that information significantly changed pesticide choices, which were assessed using stated choice experiments and actual purchase decisions before and after the information intervention. We find that farmers held an erroneous positive price-quality perception for pesticides prior to receiving information, and that information effectively broke that perception. Importantly for health, farmers chose less toxic pesticides more often after receiving information on relative toxicities and health risks. Essay 3 presents a detailed assessment of farmer pesticide knowledge using 22 questions covering pesticide control properties and health risks. We find that Zambian tomato farmers generally know pesticides are harmful to their health, but they lack product-specific knowledge on pesticide toxicity and pesticide control properties. The training program caused an increase in overall pesticide knowledge with large increases in toxicity knowledge, pest control knowledge, and pesticide efficacy knowledge. The effects of information on protective equipment knowledge were insignificant.