Prenatal Exposure to Perfluoroalkyl Substances and Mental Health in Childhood

Abstract

BACKGROUND AND AIM: Epidemiological studies have evaluated the effect of prenatal exposure to perfluoroalkyl substances (PFAS) on neurobehavioral and cognitive endpoints in childhood, but a research focus on mental health is lacking. We evaluated the associations between prenatal PFAS exposure and mental health including depressive symptoms, physical or emotional stress, and psychosis-like experience in children at age 11. METHODS: Using pooled samples in the Danish National Birth Cohort established between 1996 and 2002 (N=2,250), we estimated the associations between concentrations of six types of PFAS in maternal plasma (median, 8 gestational weeks) and child self-report mental health outcomes using validated questionnaires. Binary classifications (with or without moderate/severe symptoms) for each of the outcomes and continuous outcome variables were analyzed. We used unconditional logistic regressions to estimate the adjusted odds ratio (OR) and 95% confidence interval (CI) for the binary outcomes according to log2-transformed PFAS concentrations and PFAS tertiles. PFAS mixture by using the weighted-quantile-sum index was conducted. Analyses were repeated using negative binomial regressions for continuous count outcome variables. Sex-specific analyses were conducted. RESULTS:The highest exposure tertile for perfluorooctanoic acid (OR=1.34, 95% CI: 1.06, 1.71), perfluorohexane sulfonate (OR=1.43, 95% CI: 1.06, 1.92) and perfluoroheptane sulfonate (OR=1.37, 95% CI: 1.02, 1.84) were associated with elevated physical or emotional stress in childhood. The WQS index for PFAS mixture was also positively associated with stress in childhood (OR=1.21, 95% CI: 1.05, 1.40). There were no consistent associations found for these PFAS compounds and depressive symptoms or psychosis-like experience. Findings from negative binomial regressions were similar. There were also no apparent differences in analyses stratified by sex. CONCLUSIONS:Higher prenatal levels of three PFAS compounds and PFAS mixtures might influence physical and emotional stress in childhood. More research of fetal exposures to environmental pollutants and mental health risk in the offspring would be needed. KEYWORDS: PFAS, Mental health outcomes, Children's environmental health, Environmental epidemiology