Influence of maternal age and duration of pregnancy on serum concentrations of polychlorinated biphenyls and hexachlorobenzene in full-term neonates.

Polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) are ubiquitous carcinogenic and teratogenic compounds that are transplacentally transferred from mother to fetus during pregnancy. It was the aim of the present study to evaluate the possible influence of maternal age and duration of pregnancy on the neonatal burden with these substances. Blood samples were taken from 80 full-term German neonates within the first 12 h of life, before the first oral feeding. The serum concentrations of six PCB congeners (28, 52, 101, 138, 153, and 180) and HCB were determined with capillary gas chromatography with electron capture detection. The concentrations of the lower chlorinated PCB congeners (28, 52, and 101) were below the detection limit. PCB 153 showed the highest serum concentration (median 0.42 microg/l), followed by PCB 138 (0. 34 microg/l) and PCB 180 (0.17 microg/l). Total PCB concentration was 0.96 microg/l, HCB concentration 0.61 microg/l. All detectable PCB congeners and the total PCB concentration correlated significantly with the gestational age of the newborns (r = 0.2639; p < 0.01), with 50-140% higher serum levels in children born at 42 weeks of gestation as compared with neonates born in the 38th week. HCB concentration correlated with maternal age (r = 0.249; p < 0.01), with 2.7-fold higher serum levels in offspring of 40-year-old as compared with 20-year-old women. It is concluded that the neonatal burden with organochlorine compounds depends on maternal age and duration of pregnancy, thereby reflecting the increase in body pollution with these substances during human life as well as a continuous transplacental transfer from mother to fetus during pregnancy.