Experimental studies suggest that prenatal exposure to endocrine disrupting chemicals interferes with developmental processes in the foetal brain. Yet, epidemiological evidence is inconclusive. In a birth cohort (2008-2010, upstate New York), the authors quantified concentrations of perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and bisphenol A (BPA) in stored newborn dried blood spots using liquid chromatography/tandem mass spectrometry. Mothers reported on children’s behaviour using the Strengths and Difficulties Questionnaire at age 7 (650 singletons and 138 twins). Difficulties in total behaviour (i.e., emotional, conduct, hyperactivity, and peer problems) and prosocial behaviour were classified using validated cut-offs. Logistic regression with generalised estimating equations was used to estimate the odds of having difficulties per exposure category. In total, 111 children (12.1%) had total behavioural difficulties and 60 (6.5%) had difficulties in prosocial behaviour. The median (interquartile range) of PFOS, PFOA, and BPA were 1.74?ng/ml (1.33), 1.12?ng/ml (0.96), and 7.93?ng/ml (10.79), respectively. Higher PFOS levels were associated with increased odds of having behavioural difficulties (OR per SD of log PFOS?=?1.30, 95%CI: 1.03-1.65). Associations were observed between PFOS in the highest relative to the lowest quartile and behavioural difficulties (OR for PFOS1.14-1.74?=?1.65, 95%CI: 0.84-3.34; PFOS1.75-2.47?=?1.73, 95%CI: 0.87-3.43; and PFOS>2.47?=?2.47, 95%CI: 1.29-4.72 compared to PFOS<1.41). The associations between higher concentrations of PFOS and behavioural difficulties at age 7 years were driven by problems in conduct and emotional symptoms. Higher PFOA levels were associated with difficulties in prosocial behaviour (OR?=?1.35, 95%CI: 1.03-1.75). There was an inverse association between BPA concentrations and difficulties in prosocial behaviour but only in the 2nd and 4th quartiles. No interactions were found between sex and chemical concentrations. Increasing prenatal exposure to PFOS and PFOA, as reflected in neonatal concentrations, may pose risk for child behavioural difficulties.
Authors: Ghassabian A, Bell EM, Ma WL, Sundaram R, Kannan K, Buck Louis GM, Yeung E. ; Full Source: Environmental Pollution. 2018 Sep 27;243(Pt B):1629-1636. doi: 10.1016/j.envpol.2018.09.107. [Epub ahead of print]