Biomonitoring of Organochlorine Pesticides and Polychlorinated Biphenyls in Paired Placental Tissue and Umbilical Cord Blood in IUGR and Control Pregnancies

Abstract

Persistent organic pollutants, such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), can persist in the human body and reach the fetus via transplacental transfer. In this exploratory pilot case-control biomonitoring study, we measured selected OCPs and PCBs in paired placental tissue and umbilical cord blood obtained at delivery from 22 singleton pregnancies in Kütahya, Türkiye, which included 12 intrauterine growth restriction (IUGR) cases and 10 controls. Fifteen target analytes were quantified by GC-ECD following solid-phase extraction using Oasis HLB cartridges. Most measurements fell below the limit of quantification (LOQ), so detectability (≥LOQ vs. <LOQ) was used as the main endpoint. At least one analyte was quantified in 7 of 22 placental samples and in 7 of 22 cord blood samples. Placental quantifications included γ-HCH, o,p′-DDT, PCB-101, PCB-118 and o,p′-DDD, while cord blood quantifications were limited to p,p′-DDD, PCB-118 and o,p′-DDE. No significant differences in analyte detectability were observed between IUGR and control pregnancies. Due to the low detection rate, this study had limited statistical power to establish a definitive association between POP exposure and IUGR. These results indicate that paired placental tissue–cord blood biomonitoring is a feasible approach for interpreting low-level OCP and PCB exposure in Türkiye. Because of the small sample size and low detection frequencies, the study should be interpreted as an exploratory, hypothesis-generating pilot study rather than as a definitive assessment of the association between POP exposure and IUGR.