Organochlorine pesticide residues were determined for adipose tissue samples of 25 persons from El Paso, Texas, during the fall of 1983 and spring of 1984. DDT occurred in 72 percent of the samples with a mean value of 1.50 ppm, while the DDT breakdown product, DDE, occurred in 100 percent of the samples with a higher mean level of 4.96 ppm. This indicates primarily past widespread exposure for DDT, or possibly current food and water sources from areas of past DDT application. Lindane occurred in 96 percent of the samples, with a mean value of 0.20 ppm, and no breakdown products were detected This indicates widespread, more recent exposure for lindane, from a dispensed source such as water or food Heptachlor and its breakdown product, heptachlor epoxide, occurred in 44 percent and 12 percent of the samples, with mean value of 0.12 ppm and 0.01 ppm respectively. This indicates more recent, possibly area-related exposure for heptachlor.