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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: Fine particulate matter (PM2.5) has been found to be detrimental to respiratory health of children, but few studies have examined the effects of prenatal PM2.5 oxidative potential (OP) on lung function in infants and preschool children. OBJECTIVES: We estimated the associations of personal exposure to PM2.5  and OP during pregnancy on offspring objective lung function parameters and compared the strengths of associations between both exposure metrics. METHODS: We used data from 356 mother–child pairs from the SEPAGES cohort. PM filters collected twice during a week were analyzed for OP, using the dithiothreitol (DTT) and the ascorbic acid (AA) assays, quantifying the exposure of each pregnant woman. Lung function was assessed with tidal breathing analysis (TBFVL) and nitrogen multiple-breath washout (N2MBW) test, performed at 6 wk, and airwave oscillometry (AOS) performed at 3 y. Associations of prenatal PM2.5  mass and OP with lung function parameters were estimated using multiple linear regressions. RESULTS: In neonates, an interquartile (IQR) increase in OPDTTv (0.89nmol/min/m³) was associated with a decrease in functional residual capacity (FRC) measured by N2MBW  [β = -2.26 mL ; 95% confidence interval (CI): -4.68, 0.15]. Associations with PM2.5  showed similar patterns in comparison with OPDTTv  but of smaller magnitude. Lung clearance index (LCI) and TBFVL parameters did not show any clear association with the exposures considered. At 3 y, increased frequency-dependent resistance of the lungs (Rrs7-19) from AOS tended to be associated with higher OPDTTv  (β = 0.09hPa×s/L ; 95% CI: -0.06, 0.24) and OPAAv  (IQR = 1.14nmol/min/m³ ; β = 0.12hPa×s/L ; 95% CI: -0.04, 0.27) but not with PM2.5  (IQR = 6.9µg/m³ ; β = 0.02hPa×s/L ; 95% CI: -0.13, 0.16). Results for FRC and Rrs7-19 remained similar in OP models adjusted on PM2.5. DISCUSSION: Prenatal exposure to OPDTTv was associated with several offspring lung function parameters over time, all related to lung volumes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Studies characterizing associations between phenols, phthalates and thyroid hormones during pregnancy produce inconsistent results. This divergence may be partly attributable to false positives due to multiple comparison testing of large numbers of chemicals, and measurement error as studies rely on small numbers of biospecimens despite high intra-individual variability in urinary chemical metabolite concentrations. OBJECTIVES: This study employs a priori chemical filtering and expanded urinary biomonitoring to evaluate associations between phenol/phthalate exposures and serum thyroid hormones assessed during pregnancy. METHODS: A two-tiered approach was implemented: a) In vitro high-throughput screening results from the ToxCast/Tox21 database, as informed by a thyroid Adverse Outcome Pathway network, were evaluated to select phenols/phthalates with activity on known and putative molecular initiating events in the thyroid pathway; and b) Adjusted linear regressions were used to study associations between filtered compounds and serum thyroid hormones measured in 437 pregnant women recruited in Grenoble area (France) between 2014 and 2017. Phenol/phthalate metabolites were measured in repeated spot urine sample pools (median: 21 samples/women). RESULTS: The ToxCast/Tox21 screening reduced the chemical set from 16 to 13 and the associated number of statistical comparisons by 19%. Parabens were negatively associated with free triiodothyronine (T3) and the T3/T4 (total thyroxine) ratio. Monobenzyl phthalate was positively associated with total T4 and negatively with the T3/T4 ratio. Effect modification by iodine status was detected for several compounds (among them ∑DEHP and mono-푛-butyl phthalate) that were associated with some hormones among women with normal iodine levels. CONCLUSION: For these chemicals, screening for compounds with an increased likelihood for thyroid-related effects and relying on repeated urine samples to assess exposures improved the overall performance of multichemical analyses of thyroid disruption. This approach may improve future evaluations of human data for the thyroid pathway with implication for fetal health and may serve as a model for evaluating other toxicity outcomes. [ABSTRACT FROM AUTHOR]

While strong evidence supports adverse effects of pre-natal air pollution on child's lung function, previous studies rarely considered fine particulate matter (PM 2.5) or the potential role of offspring sex and no study examined the effects of pre-natal PM 2.5 on the lung function of the newborn. We examined overall and sex-specific associations of personal pre-natal exposure to PM 2.5 and nitrogen (NO 2) with newborn lung function measurements. This study relied on 391 mother-child pairs from the French SEPAGES cohort. PM 2.5 and NO 2 exposure was estimated by the average concentration of pollutants measured by sensors carried by the pregnant women during repeated periods of one week. Lung function was assessed with tidal breathing analysis (TBFVL) and nitrogen multiple breath washout (N 2 MBW) test, performed at 7 weeks. Associations between pre-natal exposure to air pollutants and lung function indicators were estimated by linear regression models adjusted for potential confounders, and then stratified by sex. Mean exposure to NO 2 and PM 2.5 during pregnancy was 20.2 μg/m3 and 14.3 μg/m3, respectively. A 10 μg/m3 increase in PM 2.5 maternal personal exposure during pregnancy was associated with an adjusted 2.5 ml (2.3%) decrease in the functional residual capacity of the newborn (p-value = 0.11). In females, functional residual capacity was decreased by 5.2 ml (5.0%) (p = 0.02) and tidal volume by 1.6 ml (p = 0.08) for each 10 μg/m3 increase in PM 2.5. No association was found between maternal NO 2 exposure and newborns lung function. Personal pre-natal PM 2.5 exposure was associated with lower lung volumes in female newborns, but not in males. Our results provide evidence that pulmonary effects of air pollution exposure can be initiated in utero. These findings have long term implications for respiratory health and may provide insights into the underlying mechanisms of PM 2.5 effects. • Personal exposure measurements to PM 2.5 and NO 2 are conducted repeatedly during pregnancy. • Early measurements of child lung function are performed at 2 months of age. • Personal prenatal PM 2.5 exposure, but not NO 2 , is associated with lower lung volumes in female newborns, but not in males. • Pulmonary effects of air pollution exposure can be initiated in utero. [ABSTRACT FROM AUTHOR]

Background: Data concerning the effects of prenatal exposures to phthalates and phenols on fetal growth are limited in humans. Previous findings suggest possible effects of some phenols on male birth weight.Objective: Our aim was to assess the relationships between prenatal exposures to phthalates and phenols and fetal growth among male newborns.Methods: We conducted a case-control study on male malformations of the genitalia nested in two French mother-child cohorts with recruitment between 2002 and 2006. We measured, in maternal urinary samples collected between 6 and 30 gestational weeks, the concentrations (micrograms per liter) of 9 phenol (n = 191 pregnant women) and 11 phthalate metabolites (n = 287). Weight, length, and head circumference at birth were collected from maternity records. Statistical analyses were corrected for the oversampling of malformation cases.Results: Adjusted birth weight decreased by 77 g [95% confidence interval (CI): -129, -25] and by 49 g (95% CI: -86, -13) in association with a 1-unit increase in ln-transformed 2,4-dichlorophenol (DCP) and 2,5-DCP urinary concentrations, respectively. Benzophenone-3 (BP3) ln-transformed concentrations were positively associated with weight (26 g; 95% CI: -2, 54) and head circumference at birth (0.1 cm; 95% CI: 0.0, 0.2). Head circumference increased by 0.3 cm (95% CI: 0.0, 0.7) in association with a 1-unit increase in ln-transformed BPA concentration. For phthalate metabolites there was no evidence of monotonic associations with birth weight.Conclusions: Consistent with findings of a previous study, we observed evidence of an inverse association of 2,5-DCP and a positive association of BP3 with male birth weight. [ABSTRACT FROM AUTHOR]

For non-persistent chemicals such as phthalates, a single spot urine sample only reflects exposure in the past few hours. Collecting repeated urine samples for each participant over windows of sensitivity is expected to improve exposure characterization but has rarely been done. We aimed to rely on within-subject pools of repeated urine samples to assess phthalate exposure during pregnancy and infancy. Women of the French SEPAGES mother-child cohort were asked to collect three urine samples per day over seven consecutive days, twice during their pregnancy (approximatively second (T2) and third (T3) trimesters). For their infants they also collected one sample per day during a week at two (M2) and twelve months (M12). Samples were pooled (within-subject, within-period) prior to phthalate and DINCH metabolite concentrations assessment. Number of pooled samples assayed was 477, 456, 152 and 100 for T2, T3, M2 and M12, respectively. All metabolites were detected in more than 95% of the pooled samples except for the two DINCH metabolites (oh- and oxo-MINCH), MMCHP and oh-MPHP at M2 for which detection frequencies ranged between 64% and 88%. Maternal concentrations of MiBP, MBzP, DEHP metabolites and oxo-MiNP decreased between 2014 and 2017, whereas concentrations of oh-MiNP and the two DINCH metabolites increased (Mann-Kendall p-values < 0.05). While improved compared to studies that relied on spot samples, Intraclass Correlation Coefficients for the pregnancy were below 0.40 for most metabolites. Spearman correlation coefficients between pooled samples collected in infancy were lower than those observed during pregnancy, and were all below 0.30. Exposure to emerging phthalate substitutes such as DINCH and DPHP seems widespread among pregnant women and infants. Collecting repeated urine samples in pregnant women and infants is feasible. The relatively low correlation across trimesters and between maternal and infant samples highlights the need to collect biospecimens in the assumed sensitive time window. [Display omitted] • Repeated urine samples were collected and pooled within-subject, within period. • Metabolites of phthalates and DINCH were measured in pooled samples. • Frequencies of detection were overall high. • Pregnancy concentrations of MiBP, MBzP, DEHP and oxo-MINP decreased with time. • Pregnancy concentrations of oh-MiNP and DINCH metabolites increased with time. Relying on a recent cohort (2014–2017) with repeated urine samples collected during pregnancy and infancy, we showed that exposure to phthalates and DINCH is still widespread in the general population. [ABSTRACT FROM AUTHOR]

Introduction: Hypertensive disorders during pregnancy are one of the leading causes of maternal and offspring mortality and morbidity. Exposure to environmental chemicals is suspected to increase blood pressure (BP) but few studies have investigated the impact of non-persistent chemicals, in particular among pregnant women.Methods: Women included in the study were 152 volunteer participants in the Human Early-Life Exposome (HELIX) project. They provided 3 urine samples daily over one week in two pregnancy trimesters (at around 18 and 32 weeks of gestation) to assess their exposure to phthalates (10 metabolites), phenols (7 compounds) and organophosphate pesticides (4 metabolites). BP was measured at the end of the two collection weeks. Associations between biomarkers of exposure and BP were investigated using generalized estimating equations (GEE) and linear regression, and adjusted for potential confounders.Results: A significant decrease in systolic and/or diastolic BP was observed with exposure to some phthalate metabolites, BPA, and parabens (e.g. β GEE models for systolic BP = -0.91 mmHg (95%CI: -1.65; -0.17) per doubling of BPA concentrations). These associations were more frequently observed in the second trimester of pregnancy and remained statistically significant after correction for multiple testing for BPA only. No associations were observed with organophosphate pesticides.Conclusion: This study investigates the effect of exposure to non-persistent chemicals assessed using multiple biospecimens per subject on BP during pregnancy and suggests that higher exposure to some phthalates and phenols but not pesticides is associated with lower BP during pregnancy. [ABSTRACT FROM AUTHOR]

Studies of air pollution effects during pregnancy generally only consider exposure in the outdoor air at the home address. We aimed to compare exposure models differing in their ability to account for the spatial resolution of pollutants, space–time activity and indoor air pollution levels. We recruited 40 pregnant women in the Grenoble urban area, France, who carried a Global Positioning System (GPS) during up to 3 weeks; in a subgroup, indoor measurements of fine particles (PM 2.5 ) were conducted at home (n = 9) and personal exposure to nitrogen dioxide (NO 2 ) was assessed using passive air samplers (n = 10). Outdoor concentrations of NO 2 , and PM 2.5 were estimated from a dispersion model with a fine spatial resolution. Women spent on average 16 h per day at home. Considering only outdoor levels, for estimates at the home address, the correlation between the estimate using the nearest background air monitoring station and the estimate from the dispersion model was high (r = 0.93) for PM 2.5 and moderate (r = 0.67) for NO 2 . The model incorporating clean GPS data was less correlated with the estimate relying on raw GPS data (r = 0.77) than the model ignoring space–time activity (r = 0.93). PM 2.5 outdoor levels were not to moderately correlated with estimates from the model incorporating indoor measurements and space–time activity (r = − 0.10 to 0.47), while NO 2 personal levels were not correlated with outdoor levels (r = − 0.42 to 0.03). In this urban area, accounting for space–time activity little influenced exposure estimates; in a subgroup of subjects (n = 9), incorporating indoor pollution levels seemed to strongly modify them. [ABSTRACT FROM AUTHOR]

Distribution of the phenol urinary concentrations adjusted for specific gravity in the SEPAGES cohort during pregnancy (periods second (N T2 = 477) and third trimesters ((N T3 = 456), and infancy (2 months (N M2 = 152) and 1 year (N Y1 = 100). Compounds with less than 4% detection are not shown (bisphenols F, B, AF and triclocarban). For the bisphenol A infant samples (2 months and 1 year) the concentrations of the conjugated form instead of the total form are presented as external contamination was suspected. Abbreviations: LOD = limit of detection, LOQ = limit of quantification. • Phenol concentrations were assessed accurately through the collection of repeated samples. • Pregnancy and early infancy, sensitive yet rarely analyzed periods were studied. • High detection rates of bisphenol A, parabens and triclosan in mothers and infants. • Concentrations for several phenols were higher at 12 months than during pregnancy. • Cashiers had higher bisphenol S but not bisphenol A levels than unemployed women. Parabens, bisphenol A and triclosan have been forbidden or restricted in specific types of consumer goods in Europe and France. Limited biomonitoring data are available in France since the implementation of these regulations, and exposure data on infants is scarce worldwide. Understanding the predictors of phenol urinary concentrations will help identify potential targets for prevention. We described levels, variability and predictors of exposure to 12 phenols in pregnant women and infants recruited between 2014 and 2017 in a French couple-child cohort. Among 479 pregnant women and 150 of their infants, we studied phenol urinary concentrations in within-subject, within-period pools of repeated urine samples collected during the second and third trimesters of pregnancy (up to 42 samples per woman), at 2 months and 12 months (up to 14 samples per infant). Time trends and associations with demographic, protocol, occupational and behavioral factors were studied using interval censored models to accommodate for undetected and unquantified urine concentrations. Detection rates were above 90% for bisphenol A, ethylparaben, methylparaben, benzophenone-3 and triclosan and below 5% for bisphenol AF, B, F and triclocarban. Median levels of bisphenol A, bisphenol S, methylparaben, ethylparaben and propylparaben at 12 months were similar or higher than during pregnancy. For pregnant women all phenols but benzophenone-3 and bisphenol S showed a linear decrease between 2014 and 2017 (p-values < 0.02). Women with the shortest education (primary and secondary school) had higher urinary concentrations of triclosan (β = 0.58 (95% confidence interval (CI), −0.04; 1.20)), ethyl (β = 0.43 (95%CI, 0.03; 0.84)) and propyl paraben (β = 1.39 (95%CI, 0.55; 2.24)) than those with the longest education. Cashiers had higher conccentrations of bisphenol S (β = 0.99 (95%CI, −0.11; 2.09)) but not of bisphenol A (β = −0.04 (95%CI, −0.26; 0.19)) than unemployed women. Despite recent regulations, bisphenol A, triclosan and paraben detection rates were high in women and young infants. High bisphenol and paraben median levels at 12 months require further investigation as early infancy is a sensitive period for exposure to environmental contaminants. [ABSTRACT FROM AUTHOR]