Biomarkers of exposure to organophosphorous insecticides among farmers' families in rural El Salvador: factors associated with exposure.

Most studies of the health effects of pesticides have concentrated on occupational exposure. Little is known about community environmental exposure to agricultural pesticides. The purpose of this study was to investigate nonoccupational pesticide exposure among farmers' families in rural El Salvador, a country known for intensive use of extremely toxic compounds. The study population included all residents 8 years and older living in five agricultural communities in El Salvador. Current exposure to organophosphate insecticides (OPs) was established through analysis of urine samples for alkyl phosphate metabolites of OPs. Nearly half of 358 analyzed samples had detectable levels of OP metabolities. Of subjects not performing agricultural fieldwork, 30% nonetheless excreted detectable levels of metabolities. Similar rates held for children and adults. The best independent predictors for an individual's excretion of OP metabolites were (a) performing fieldwork during the past 2 weeks, (b) the head household farmer's application of OPs during the past 2 years, and (c) the household mother reporting use of OPs in the home or yard. The latter factors were significantly associated with metabolite excretion regardless of whether the individual had done fieldwork. The results of this study support the hypothesis that a large proportion of rural Salvadorans, including children, is exposed to pesticides through environmental as well as occupational routes.