Exposure to endocrine disrupting chemicals and behaviors associated with ADHD in adolescents

Abstract

TPS 731: Neurological effects in children, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background: Phthalates and parabens are endocrine disrupting chemicals (EDCs) commonly found in personal care products. Studies suggest that exposure to EDCs may influence childhood behaviors associated with attention deficit/hyperactivity disorder (ADHD), but the relationship during adolescence has not been studied. Methods: Urinary biomarker concentrations of phthalates and parabens commonly found in personal care products were quantified in 152 adolescents (age ~15 yrs) in the New Bedford Cohort, a birth cohort study among residents near the New Bedford Harbor Superfund site, Massachusetts. ADHD-associated behavior was assessed with multiple indices from self, parent, and teacher completed behavioral checklists using the Conners’ Attention Deficit Scale and the Behavior Assessment System for Children, 2nd ed., where higher scores indicate more problem behaviors. We used a repeated measures analysis with negative binomial models to estimate the adjusted association of each analyte with these multiple measures of ADHD-related behavior. Results: In this racially diverse (38% non-white or Hispanic) and socioeconomically disadvantaged (31% in low income households, 43% had unmarried mothers, 59% had mothers with a high school education or less) population, a doubling in urinary concentration of the molar sum of paraben biomarkers was associated with an 2% increase in behavior score associated with ADHD in girls (95% CI: 1.01, 1.04), but not boys; this association appeared to be driven by propyl and methyl paraben. We also observed a 3% increase in the ADHD-related behavior score in both sexes with a doubling of the molar sum of urinary phthalate biomarkers commonly found in personal care products (95% CI: 1.01, 1.04); this association was predominantly driven by monobutyl phthalate (%diff: 1.04, 95% CI: 1.02, 1.07), although we observed a smaller significant association with mono-iso-butyl phthalate. Conclusion: Our findings suggest that exposure to some parabens and phthalates during adolescence may be associated with behaviors characteristic of ADHD.