Abstracts: ISEE 20th Annual Conference, Pasadena, California, October 12–16, 2008: Symposium Abstracts
Pesticide Exposures in Imperial County
Pesticides are a ubiquitous component of our environment. Over 1 billion pounds of pesticides are applied in the United States each year. Pesticide use in agricultural communities is much higher than urban and non-agricultural communities. Higher pesticide use has been linked to higher exposure to these chemicals and most cases of pesticide poisoning occur among farmers and workers in farms. Imperial County east of San Diego is a small agriculture community on the California/Baja California border. It is mostly composed of Latinos/Hispanics and has a lower than average family income and education. Imperial County has been shown to be one of the highest areas of use of pesticide in southern most area of California and up to 8.5 times higher use than San Diego. All use of pesticides is recorded with the California Department of Pesticide Regulation and therefore we can predict what types of pesticides are used in a certain community such as Imperial County. Soil sampling and analyses for different pesticides in the county revealed 5 pesticides to be consistently present (DDD, DDE, chlorthal-dimethyl, diazinon, and trifluralin). Trifluralin was the highest in terms of level of detection in soil samples. Trifluralin has been listed by the EPA as a carcinogen. However, it is still not known how these environmental exposures are related to human exposure among the population living in this county. The literature is inconsistent but suggestive of an association between pesticide exposure and cancer risk. In more than 30 studies from the literature, the majority indicate an association between pesticides and/or farming and Non-Hodgkins Lymphoma and Leukemia. However, these studies only rely on the type of occupation or on ecological studies to assess exposure to pesticides, leading to poor assessment of exposure. Poor exposure measures lead to attenuation of the true associations and can explain the inconsistent and weak findings. The use of biomarkers in epidemiology are expected to improve our estimation of true associations because of more accurate measurement of exposure. The risk of pesticide exposure in Imperial County, a disadvantaged community on Southern California's border, is not well addressed and needs further investigation.© 2008 Lippincott Williams & Wilkins, Inc.