Numerous studies indicate that exposure to environmental stressors during gestation, infancy, and early childhood is a risk factor for diseases in childhood and adulthood. One class of chemical, endocrine-disrupting chemicals (EDCs), might increase the risk of childhood diseases by disrupting hormone-mediated processes that are critical for growth and development during gestation, infancy and childhood. The fetus, infant, and child might have enhanced sensitivity to environmental stressors such as EDCs due to their rapid development and increased exposure to some EDCs as a consequence of development-specific behavior and higher ventilation rates, intestinal absorption, surface area to volume ratios, and hand-to-mouth activity.
[Photo: Dr. Joseph Braun]
The purpose of this review, by Dr. Joseph Braun, assistant professor of epidemiology and faculty member in the Center for Environmental Health and Technology, was to explore epidemiological studies examining the relationship between early-life exposure to bisphenol A (BPA), phthalates, triclosan, and perfluoroalkyl substances (PFAS) with childhood neurobehavioral disorders and obesity.
The available epidemiological evidence suggest that exposure to BPA, phthalates, triclosan, and PFAS is ubiquitous and occurs during potentially sensitive periods of development that are important in the aetiology of childhood neurodevelopmental disorders and obesity. Prenatal BPA and phthalate exposures are related to adverse neurobehavioral outcomes in children. Furthermore, prenatal PFAS exposure is related to reduced fetal growth and excess childhood adiposity.
Quantifying the effects of EDC mixtures, improving EDC exposure assessment, reducing bias from confounding, identifying periods of heightened vulnerability and elucidating the presence and nature of sexually dimorphic EDC effects would enable stronger inferences to be made from epidemiological studies than currently possible. Ultimately, improved estimates of the causal effects of EDC exposures on child health could help identify susceptible subpopulations and lead to public health interventions to reduce these exposures.
This study was published in Nature Reviews Endocrinology (ahead of print).
For more information: https://www.ncbi.nlm.nih.gov/pubmed/27857130