When more is less: health-mediated income losses from pesticide spraying among cowpea farmers in Ghana

Despite the widespread use of pesticides to control insect pests, relatively little is known about whether their economic benefits are offset by the adverse health effects experienced by smallholder farmers. This study examines both the direct economic influence of pesticide spraying and the indirect influence operating through farmer health among 615 smallholder cowpea farmers in Ghana. To address potential endogeneity in spraying decisions and explore a possible health-related pathway, we estimate an instrumental variable two-stage least squares (IV-2SLS) model together with an IV mediation analysis. The results suggest that each additional pesticide application is associated with an approximately 18% reduction in gross cowpea revenue. The mediation analysis indicates that adverse health symptoms may constitute an important pathway through which intensive pesticide spraying is associated with lower cowpea revenue. These findings suggest that promoting economically efficient pesticide use should be accompanied by strategies that reduce farmers’ exposure to pesticide-related health risks, thereby supporting both farmer well-being and more sustainable crop production.