Prenatal Exposure to Perfluoroalkyl Substances and Behavioral Development in Children

Abstract

Background: In recent years, prevalence rates of behavioral disorders in children have increased. One factor possibly implied in the etiology of behavioral disorders is exposure to perfluoroalkyl substances (PFASs). The use of PFASs is highly integrated into everyday life, and exposure is ubiquitous. Exposure to PFASs during early life may be particularly harmful, as it represents a critical time window for brain development. However, research in the area is limited, especially among preschool children. The objective of the current study was to explore the relationship between prenatal exposure to several PFASs and behavioral development at the age of 18 months. Methods: Data from the Dutch cohort LINC (Linking Maternal Nutrition to Child Health) were used. Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were measured in cord plasma. The total exposure of PFASs was also calculated (ΣPFASs). Behavioral development was assessed with the Child Behavior Checklist 1.5–5 (CBCL 1.5–5). The CBCL scales “Attention Deficit Hyperactivity Disorder” (ADHD) and “Externalizing problems” were used for further analysis. Separate regression models were composed for each combination, in which exposure levels were classified in tertiles. Both whole population and sex-stratified analyses were performed. A family history of ADHD, the educational level, smoking or using alcohol or illicit drugs during pregnancy were considered as confounders. In total, data from 76 mother-child pairs was included. Results: No significant associations were found between prenatal PFAS exposure and ADHD scores in the whole population and in the sex-stratified analyses. With regard to externalizing behavior, a significant negative association was found between the highest levels of ΣPFAS exposure and externalizing problem behavior in the whole population, but only in the crude model. After stratifying for sex, boys in the second and third tertile of exposure to PFOA presented significantly lower scores on the Externalizing Problem Scale than boys with the lowest exposure levels in the adjusted model. Girls exposed to higher levels of ΣPFAS exposure (T2) showed significantly lower scores on the Externalizing Problem Scale, in both crude and adjusted models. No significant associations with PFOS were found. Conclusions: Results from the current study show that prenatal exposure to PFOA was negatively related to externalizing behavior in boys. Results were different for boys and girls, emphasizing that mechanisms at work might be sex-dependent. However, results should be interpreted with caution as the sample size was small.

Developmental Exposures to Perfluoroalkyl Substances (PFASs): An Update of Associated Health Outcomes

“…In this cohort, infants with hypotonic phenotypes had lower psychomotor development and lower externalizing scores at 2–3 years of age [88]. A small Dutch cohort examined 76 children 18 months of age and found no associations between prenatal PFAS exposure and ADHD scores, but externalizing behavior in boys appeared to be related to prenatal PFOA level [86]. Lastly, the Norwegian birth cohort also found no associations between breastmilk levels of PFOS and PFOA and early neuropsychological development at 12 and 24 months [87].…”

“… The studies in the table are listed according to the continent (in order of America, Europe and Asia), country (alphabetical order) and year of publication. a Three cross-sectional studies [83–85], one small study less than 100 subjects [86] and one study that evaluated PFASs in breastmilk [87] are not listed in the table. …”

“… a Three cross-sectional studies [83–85], one small study less than 100 subjects [86] and one study that evaluated PFASs in breastmilk [87] are not listed in the table. …”

Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) acutely affect human α1β2γ2L GABAA receptor and spontaneous neuronal network function in vitro

“…neurodevelopmental or neurological effects of PFAS exposure 16,18,[21][22][23] , although recent epidemiological studies indicate an association between PFAS exposure and child behaviour 24,25 . It is important to keep in mind that exposure to PFAS in these studies is continuous and/or based on prolonged exposure paradigms.…”

Gestational exposure to perfluorooctanoic acid (PFOA): Alterations in motor related behaviors

“…However, individuals gestationally exposed to PFOA at 10x higher serum concentrations showed increased odds ratio of being categorized as hypotonic rather than social/easygoing. Studies of children from the Swedish cohort or the Dutch cohort Linking Maternal Nutrition to Child Health reported no PFOA exposure-related association with attention deficit hyperactivity disorder (Ode et al, 2014; Quaak et al, 2016). Recent studies with a Danish cohort found no evidence of exposure-related associations between maternal serum concentrations of PFOA and offspring behavioral or affective disorders, including scholastic achievement over a 20-yr follow-up period (Strom et al, 2014) or in increased risk of attention deficit/hyperactivity disorder or autism (Liew et al, 2015).…”