Association of prenatal exposure to polychlorinated biphenyls with cleft lip and/or palate risk in offspring: A case-control study.

Cleft lip and/or palate (CL/P) is a congenital facial defect. Polychlorinated biphenyls (PCBs) are recognized as both persistent organic pollutants and endocrine-disrupting chemicals, which can cross the placental barrier, leading to an increased risk of adverse pregnancy outcomes. However, there is no study to evaluate the association of prenatal exposure to PCBs with CL/P risk in offspring. Therefore, we investigated a multicenter case-control study, comprising 149 cases and 292 controls, to explore the association of prenatal exposure to single PCB and a PCB mixture with CL/P risk in offspring. Thirteen PCBs were measured using a gas chromatograph coupled with a triple-quad mass spectrometer. The single exposure analysis indicated a significant statistical association of placental 2,2',5,5'-tetrachlorobiphenyl and 3,4,4',5-tetrachlorobiphenyl levels with CL/P risk (OR = 1.23, 95 % CI: 1.03, 1.48; OR = 1.20, 95 % CI: 1.03, 1.41, respectively). Three multipollutant models demonstrated a positive association between prenatal exposure to the PCB mixture and CL/P risk, with 2,2',5,5'-tetrachlorobiphenyl and 3,4,4',5-tetrachlorobiphenyl being the primary contributors to this risk. This study pioneers the investigation of the association between prenatal exposure to PCBs and the risk for CL/P, which not only deepens our understanding of the toxic effects of PCBs but also serves as a stark reminder of the urgent need to intensify efforts to remediate contaminated environments.