Prolonged exposure to pesticides can lead to cardiopulmonary disorders, neurological and hematological symptoms, and skin disease (Davies, Freed, and Whittemore, 1982; Smith, Carpenter, and Faulstich, 1988). These symptoms can lower productivity because of the farmer’s absence from work during treatment and recuperation and impaired capacity to work. Farmers who do not know about the harmful effects of pesticides sometimes overvalue their benefits and use them beyond the private and social optimum levels.