Prenatal exposure to mixtures of persistent endocrine disrupting chemicals and postnatal body size in British girls.

Abstract Background Endocrine disrupting chemical (EDC) exposure is ubiquitous. EDC exposure during critical windows of development may interfere with the body's endocrine system, affecting growth. Previous human studies have examined one EDC at a time in relation to infant growth. By studying mixtures, the human experience can be better approximated. Aims We investigated the association of prenatal exposure to persistent EDCs (per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs)) as mixtures with postnatal body size among female offspring. Subjects We used a sub-sample of the Avon Longitudinal Study of Parents and Children (N = 425), based in the United Kingdom. Study design We quantified 52 EDCs in maternal serum collected during pregnancy. We used Bayesian kernel machine regression with a random intercept to examine the association of prenatal concentrations of EDC mixtures with longitudinal postnatal body size measures for each EDC class separately (PFAS, PCBs, and OCPs) and for all three classes combined. Outcome measures Weight and height measures at 0, 2, 9, and 19 months were obtained by health professionals as part of routine child health surveillance. Results The mixture representing all three classes combined (31 chemicals) (n = 301) was inversely associated with postnatal body size. Holding all EDCs in the 31-chemical mixture at the 75th percentile compared to the 50th percentile was associated with 0.15 lower weight-for-age z-score (95% credible interval −0.26, −0.03). Weak inverse associations were also seen for height-for-age and body mass index-for-age scores. Conclusions These results suggest that prenatal exposure to mixtures of persistent EDCs may affect postnatal body size.