Prenatal exposure to persistent organic pollutants in Wuhan, China: associations with birth outcomes and breastfeeding safety

Infants are particularly vulnerable to the adverse effects of persistent organic pollutants (POPs) due to their developing physiological systems and high exposure relative to body weight. This study quantified legacy POPs in breast milk samples collected from 99 lactating mothers in Wuhan, China, and evaluated their associations with neonatal birth outcomes. The predominant organochlorine pesticides (OCPs) detected were 1,2,3,4,5,6-hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethane (DDTs) metabolites. Among polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), PCB 52 and BDE 154 were the most abundant congeners. Maternal factors, including parity, body-mass index, and dietary pattern, significantly influenced POP concentrations in breast milk. Our results revealed significant associations between specific POPs and birth outcomes. For instance, β-HCH was positively correlated with birth weight, whereas heptachlor exhibited a negative correlation. Additionally, PCB 170 was inversely correlated with infant head circumference, while BDE 28 and BDE 99 showed positive correlations. Our health-risk assessment demonstrated that, despite elevated POP levels in a subset of samples, estimated daily intakes for most breastfed infants remained below established safety thresholds. These findings reaffirm that the established​ nutritional and immunological benefits of breastfeeding far​ outweigh the potential risks from background POP exposure. Nevertheless,​ the persistent and widespread detection of these contaminants underscores the need for ongoing biomonitoring and public health interventions to reduce maternal body burdens by mitigating environmental and dietary sources.