Background
The health impacts of pesticides are difficult to assess from available secondary data in most countries. Pesticide poisonings documented by health centers represent only a small fraction of actual poisonings, for two main reasons. First, only a small number of severe poisonings (mostly suicide attempts) are treated in the health care system. Many agricultural workers do not report non-lethal cases because of the cost in time or money, inaccessibility of health care services, or fear that drawing attention to themselves may result in the loss of their job. Secondly, the relatively few farmers who do seek treatment are often misdiagnosed because pesticide poisonings can mimic other common health problems (FAO, 2001). The World Health Organization estimates that there are 50 cases of poisoning for every case reported and registered (WHO, 1990).
Survey Design
To assess the actual extent of this problem, the World Bank collaborated with the Vietnam Association of Occupational Health to study pesticide poisoning among Mekong Delta farmers in the first quarter of 2004. With 481 farmers participating, the study collected both survey and clinical data. Structured questionnaires were used to collect information on farming systems, pesticide use and practices, applicator precautions, protective measures, and self-reported poisoning symptoms. The survey was designed by the World Bank team in collaboration with the University of Economics, Ho Chi Minh City and the Vietnam Association of Occupational Health. All participating farmers were examined by the doctors from the Vietnam Association of Occupational Health. Using clinical exam results and self-reported symptoms, the study team selected potentially-poisoned farmers for blood tests that detect acute or chronic contamination by pesticides (organophosphates and carbamates).
The medical survey covered the districts of An Phu and Chau Thanh (An Giang province), Thot Not and Vi Thanh (Can Tho province), Tan Thanh and Thu Thua (Long An province ), Cai Lay and Cho Gao (Tien Giang province), and Tra Cu and Tieu Can (Tra Vinh province) in the Mekong Delta. The 482 surveyed farmers are almost all male (3 females were examined). Their ages range from 15 to 70 years, with an average age of 39. The surveyed farmers average 8 years of education; 74% report that they smoke and 48% report drinking alcoholic beverages. To minimize possible reporting bias, the surveyed farmers were assured of anonymity.
