BACKGROUND: Perfluoroalkyl substances (PFAS) are chemicals with potential neurotoxic effects although the current evidence is still limited.
OBJECTIVE: This study investigated the association between perinatal exposure to perfluoro-octanesulfonate acid (PFOS) and perfluorooctanoate acid (PFOA) and neuropsychological development assessed at 24 months.
METHODS: We measured, PFOS and PFOA in breast milk samples collected one month after delivery by mothers of 404 children participating in the HUMIS study (Norway). The concentrations of PFAS were back- calculated to estimate exposure at time of delivery which was used as proxy of perinatal exposure. Neuropsychological development was measured at 24 months using the Ages and Stages Questionnaire (ASQ-II). 351 children had complete information on exposure and neuropsychological development.
RESULTS: The back-calculated median concentration of at deli very PFOS was 141.39 ng/L, while the median for PFOA was 61.65 ng/L. An increased risk of having an abnormal score in ASQ-II communication scale was significantly associated with the highest vs. lowest tertile of PFOS exposure (OR = 5.14 [95%CI = 1.48 - 17.94]) with a significant dose-response (p- trend = 0.010).These results were replicated in the imputed models. We did not observe any other significant association between PFOS and PFOA exposure and the rest of ASQ-II sub-scales (gross motor, fine motor and personal-social).
CONCLUSION: We observed some indications for an association bet ween perinatal PFOS exposure and increased risk of abnormal language development at 24 months, but not in other neuropsychological domains tested. Further longitudinal studies are needed to confirm the effects of these compounds on neuropsychological development in older children.
