Abstract

One hundred specimens of human body fat, 50 necropsy and 50 biopsy, were collected in 1964 from a semi-rural area in south-eastern England. The specimens were analysed by two methods and the concentrations of seven organo-chlorine insecticides were determined. The results of the two analytical methods were in good agreement. Endrin and heptachlor epoxide were not detected in any of the specimens analysed for these compounds. The average concentrations of lindane, op'-DDT, and op'-DDE were very small: 0·015 p.p.m., 0·03 p.p.m., and 0·02 p.p.m. respectively. The average concentration of HEOD in the 100 specimens of fat (no significant difference in the means of the necropsy and biopsy fats was detected) was 0·21 p.p.m., as in the 1961 survey. The average concentration of total equivalent-DDT (DDT + DDE) in the 50 necropsy fats was 3·9 p.p.m., as compared with 2·2 p.p.m. in 1961. In the biopsy fats the average concentration for males was 4·9 p.p.m., and for females 3·4 p.p.m. One method was suitable for the separate determination of pp'-DDT and pp'-DDE. The average concentration of pp'-DDT was 1·0 p.p.m. in the 100 necropsy and biopsy fats. The average concentration of pp'-DDE was 2·2 p.p.m. in the 50 necropsy fats, and 3·1 p.p.m. and 2·0 p.p.m. in male and female biopsy fats respectively. The variability of the concentrations of these compounds in the necropsy specimens was generally greater than in the biopsy specimens. No significant differences were found which were attributable to age or to the cause of death. It is considered that the amounts found of these compounds do not constitute a hazard to the population sampled in this survey. The design of surveys to determine the concentrations of organo-chlorine insecticides in man is discussed.