Polychlorobiphenyl in children's blood

Specific Polychlorobiphenyl (PCB) isomer levels in blood of 30 children, ages 2-5 years, residing in an area of PCB contaminated soil, were compared to those of 25 children of the same age group from a noncontaminated residential area. The sum of individual PCB isomer levels in the exposed group was 0.54 ng/g as compared to 0.88 ng/g for the nonexposed group, and this difference was statistically not significant. The major component in both groups was the 2,2',4,4',5,5'-hexachlorobiphenyl isomer (greater than 0.1 ng/g). A statistically significant difference between the two groups of children was observed only for the 2,3',4,4'-tetrachlorobiphenyl residue level. Although the total PCB levels in the nonexposed group were somewhat higher than in the exposed group, the specific isomer distribution in the latter may support the premise of a somewhat more recent exposure. Close agreement was observed in the specific isomer content of blood from nonexposed populations between this and a Japanese study.