Cord blood BPA level and child neurodevelopment and behavioral problems : The Hokkaido Study on Environment and Children's Health

Background: Bisphenol A (BPA) is a ubiquitous environmental chemical which has been detected in various populations. There have been concerns that endocrine disrupting property of BPA may cause adverse health effects on neurodevelopmental and behavioral problems. Yet findings from prospective cohort studies to assess influence of prenatal exposure to BPA on child neural development were not conclusive. Especially, with relatively lower levels of exposure and its influence was not examined. Thus, the aim of this study was to evaluate child mental, psychomotor and behavioral problems at different ages in association with prenatal BPA exposures in the prospective birth cohort study. Method: BPA level in cord blood was determined by ID-LC/MS/MS. Bayley Scales of Infant Development 2nd Edition was used to assess mental and motor development at 6 and 18 month of age. Kaufman Assessment Battery for Children to assess intelligence and Child Behavior Checklist (CBCL) to assess behavioral problems were used at 42 month of age. Out of 514 subjects in Sapporo cohort, 285 mother-child pairs with BPA measurement and child developmental assessments were included in this study. Results: The median level of cord blood BPA was 0.051ng/ml. No association was found between BPA level and either mental or psychomotor development at 6 and 18 month of age. BPA level was positively associated with total, internalizing and externalizing problem scores of CBCL, respectively (β=4.77, 95% CI: -0.28, 9.82, β=4.35, 95% CI: -0.48, 9.18, β=4.33, 95% CI: -0.86, 9.25) with marginal significance. Cord blood BPA concentration was positively associated with development problems score (β=2.60, 95% CI: 0.15, 5.06) with significance. Conclusion: Our findings suggested no association between cord blood BPA level and child mental, psychomotor, however, cord blood BPA level may be associated with child behavioral problems at early age