Current status of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) exposure among mothers and their babies of Korea-CHECK cohort study.

Despite the global ban, organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been a persistent and significant environmental health issue worldwide. Prenatal exposure to these persistent organic pollutants (POPs) has been identified as a major route of exposure among developing fetuses and newborn infants. Among Children's Health and Environmental Health of Korea (CHECK) cohort population, pregnant females (n=148) and their matching newborn infants (n=117) recruited from four cities of Korea in 2011 were investigated. The blood serum and cord blood serum were sampled at delivery, and measured for 19 OCPs and 19 PCBs. In addition, a questionnaire regarding demographic characteristics, and dietary habits were conducted. The most frequently detected POPs in both maternal blood and cord blood were p,p'-dichlorodiphenyl dichloroethylene (DDE) (99% detection in maternal, and 98% in cord blood serum) and PCB153 (95% in maternal, 74% in cord blood serum). The levels of dichlorodiphenyl trichloroethanes (DDTs) in both maternal (average 82.5ng/g lw) and cord blood serum (average 77.5ng/g lw) were comparable to or greater than those reported in Japan about a decade ago. Approximately two thirds of the pregnant women and newborn infants showed the p,p'-DDE concentrations exceeding the biological equivalent (BE) corresponding to 10-6 excess cancer risk. In addition, less chlorinated PCBs were detected higher in both maternal and cord serum. Less chlorinated PCBs also showed greater transplacental ratio. Dairy consumption among the subjects was positively associated, and tea consumption was negatively associated with serum levels of several POPs. Our results show that the exposure to legacy POPs, especially DDTs, among pregnant women and newborn infants is still prevailing, thus warrants measures for exposure mitigation among these vulnerable populations.