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BACKGROUND: Previous studies aiming at relating exposure to phenols and phthalates with child social behavior characterized exposure using one or a few spot urine samples, resulting in substantial exposure misclassification. Moreover, early infancy exposure was rarely studied. OBJECTIVES: We aimed to examine the associations of phthalates and phenols with child social behavior in a cohort with improved exposure assessment and to a priori identify the chemicals supported by a higher weight of evidence. METHODS: Among 406 mother-child pairs from the French Assessment of Air Pollution exposure during Pregnancy and Effect on Health (SEPAGES) cohort, 25 phenols/phthalate metabolites were measured in within-subject pools of repeated urine samples collected at the second and third pregnancy trimesters (∼21 samples/trimester) and at 2 months and 1-year of age (∼7 samples/period). Social behavior was parent-reported at 3 years of age of the child using the Social Responsiveness Scale (SRS). A structured literature review of the animal and human evidence was performed to prioritize the measured phthalates/phenols based on their likelihood to affect social behavior. Both adjusted linear regression and Bayesian Weighted Quantile Sum (BWQS) regression models were fitted. False discovery rate (FDR) correction was applied only to nonprioritized chemicals. RESULTS: Prioritized compounds included bisphenol A, bisphenol S, triclosan (TCS), diethyl-hexyl phthalate (RDEHP), mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), and mono-benzyl phthalate (MBzP). With the exception of bisphenols, which showed a mixed pattern of positive and negative associations in pregnant mothers and neonates, few prenatal associations were observed. Most associations were observed with prioritized chemicals measured in 1-y-old infants: Each doubling in urinary TCS (β=0.78; 95% CI: 0.00, 1.55) and MEP (β=0.92; 95% CI: -0.11, 1.96) concentrations were associated with worse total SRS scores, whereas MnBP and RDEHP were associated with worse Social Awareness (β=0.25; 95% CI: 0.01, 0.50) and Social Communication (β=0.43; 95% CI: -0.02, 0.89) scores, respectively. BWQS also suggested worse total SRS [Beta 1=1.38; 95% credible interval (CrI): -0.18, 2.97], Social Awareness (Beta 1=0.37; 95% CrI: 0.06, 0.70), and Social Communication (Beta 1=0.91; 95% CrI: 0.31, 1.53) scores per quartile increase in the mixture of prioritized compounds assessed in 1-y-old infants. The few associations observed with nonprioritized chemicals did not remain after FDR correction, with the exception of benzophenone-3 exposure in 1-y-old infants, which was suggestively associated with worse Social Communication scores (corrected 푝=0.07). DISCUSSION: The literature search allowed us to adapt our statistical analysis according to the weight of evidence and create a corpus of experimental and epidemiological knowledge to better interpret our findings. Early infancy appears to be a sensitive exposure window that should be further investigated. [ABSTRACT FROM AUTHOR]

BACKGROUND: Consumption of an organic diet reduces exposure to a range of agricultural pesticides. Only three studies have examined the effect of an organic diet intervention on exposure to the herbicide glyphosate, the most heavily used agricultural chemical in the world. Despite its widespread use, the primary sources of glyphosate exposure in humans are poorly understood. OBJECTIVE: Our objective was to examine the effect of an organic diet intervention on urinary glyphosate concentrations among pregnant individuals. METHODS: We conducted a 2-wk randomized crossover trial in which 39 pregnant participants living near (≤0.5 km) and far (>0.5 km) from agricultural fields received a 1-wk supply of conventional groceries and 1 wk of organic groceries, randomized to order. We collected daily first morning void urine samples and analyzed composite samples from each week for glyphosate. We examined differences in urinary glyphosate concentrations between the conventional week and the organic week among all participants and stratified by residential proximity to an agricultural field. RESULTS: Median specific gravity-adjusted glyphosate concentrations were 0.19 μg/L and 0.16 μg/L during the conventional and organic weeks, respectively. We observed modest decreases in urinary glyphosate concentrations from the conventional to organic week among far-field participants, but no difference among near-field participants. In secondary analyses excluding participants who did not meet a priori criteria of compliance with the intervention, we observed significant decreases in urinary glyphosate concentrations, particularly among far-field participants (푝< 0.01-0.02, depending on exclusion criteria). DISCUSSION: This trial is the first to examine the effect of an organic diet intervention on glyphosate among people living near and far from agricultural fields. Our results suggest that diet is an important contributor to glyphosate exposure in people living >0.5 km from agricultural fields; for people living near crops, agriculture may be a dominant exposure source during the pesticide spray season. [ABSTRACT FROM AUTHOR]

BACKGROUND: Findings from national surveys suggest that everyone in the United States is exposed to perchlorate. At high doses, perchlorate, thiocyanate, and nitrate inhibit iodide uptake into the thyroid and decrease thyroid hormone production. Small changes in thyroid hormones during pregnancy, including changes within normal reference ranges, have been linked to cognitive function declines in the offspring. [ABSTRACT FROM AUTHOR]