Phthalate exposure and childrens neurodevelopment: A systematic review

Background: Emerging evidence from observational studies suggests that prenatal exposure to phthalates affects neurodevelopment in children. Objective: To conduct a systematic review of the existing literature on the association between urinary phthalate concentrations and children's neurodevelopment. Methods: We searched electronic bibliographic databases (MEDLINE, PubMed, EMBASE, PsycINFO, CINAHL, Global Health, CAB abstracts, and ERIC) (1910 to February 21st, 2014); reference lists of included articles, and conference abstracts (American Psychiatric Association, American Academy of Neurology, and Pediatric Academic Societies). Two independent reviewers screened abstracts and extracted data. We included original studies reporting on the association between prenatal or childhood urinary phthalate metabolites, and cognitive and behavioral outcomes (e.g., IQ scores, BASC-2 scores or equivalent) in children 0–12 years of age. Results: Of 2804 abstracts screened, 11 original articles met our criteria for inclusion. Conclusions: A systematic review of the literature supports the contention that prenatal exposure phthalates is associated with adverse cognitive and behavioral outcomes in children, including lower IQ, and problems with attention, hyperactivity, and poorer social communication. Further research characterizing the associations between specific phthalate metabolites and children's neurodevelopmental outcomes is needed to support the development of mitigation strategies and enhance the development of appropriate health policy. - Highlights: • Prenatal maternal urinary concentrations of phthalate metabolites appear to be associated with adverse cognitive and behavioral outcomes in children. • Both low molecular weight (e.g., monobutyl phthalate, MBP) and high molecular weight (e.g., di(2-ethylhexyl) phthalate, DEHP) phthalate metabolites are associated with adverse cognitive and behavioral outcomes. • Sex-specific effects from phthalate exposure were noted between low (e.g., mono-n-butyl phthalate, MnBP) and high (e.g., DEHP) molecular weight phthalate metabolites, and cognitive and behavioral outcomes.