An analysis of insecticide use in rice: Case studies in the Philippines and Vietnam

Abstract

The majority of pesticide applications by rice farmers in the Mekong Delta, Vietnam, and Leyte, Philippines, were insecticides. Farmers in Vietnam applied more insecticides per season (∼6.1 sprays) than Filipino farmers (∼2.6 sprays). About half of the insecticide sprays were organophosphates and the main chemicals were methyl parathion, monocrotophos, and methamidophos. About 22% and 17% of the chemicals in the Philippines and Vietnam, respectively, were classified as ‘extremely hazardous’ (Category la) by the WHO. Another 17% and 20% in the Philippines and Vietnam, respectively, were classified as ‘highly hazardous’ (Category Ib). High proportions of the sprays were targeted at leaf‐feeding insects which accounted for 42% and 28% of insecticide sprays in Vietnam and Philippines, respectively. In the Philippines, sprays against rice bugs accounted for 44% while in Vietnam, those against brown planthoppers accounted for 34%. Since research has shown that leaf feeder control generally does not increase yields, a large proportion of insecticides currently used may be unnecessary.