Organochlorine compounds in human adipose tissue from north Texas

This paper reports a preliminary study that was conducted to determine the concentrations of organochlorine compounds in the adipose tissue of residents of North Texas. Thirty-five human adipose tissue samples were obtained during autopsy between 1987 and 1988 from persons who had no known occupational exposure to organochlorine pesticides. These samples were analyzed by electron-capture gas chromatographic methods for the presence of beta-benzene hexachloride, o,p'-DDE, p,p'-DDE, o,p'-DDT, p,p'-DDT, dieldrin, oxychlordane, and heptachlor epoxide. The findings indicate greater than 97% occurrence for each compound with the exception of o,p'-DDE and o,p'-DDT, each of which occurred in 54% of the population sampled. Statistical analyses of the data showed strong positive correlations between adipose tissue concentrations and age for oxychlordane, heptachlor epoxide, p,p'-DDT, p,p'-DDE, and total DDT (the normalized sum of DDT and its analogues) (p less than or equal to .05). Statistically significant differences (p less than or equal to .05) in geometric mean concentrations between all age groups were found for total DDT and p,p'-DDE. However, the group means comparison test was only significantly different between the 41-60 yr and 61 and over age groups for p,p'-DDT, oxychlordane, and heptachlor epoxide. No statistically significant difference was found between sexes in this study. The geometric means of pesticide concentrations in adipose tissue were compared with those reported in previous U.S. Environmental Protection Agency surveys for the general population. This comparison clearly indicates a declining temporal trend in environmental exposure for banned DDT analogues; however, a consistent temporal trend exists for oxychlordane and heptachlor epoxide--pesticides whose uses are currently restricted but not proscribed.