Prenatal exposure to phthalates and phenols and infant endocrine-sensitive outcomes: The MIREC study.

Anogenital distance (AGD) and the second to fourth finger (2D:4D) digit ratio may be early markers of in utero androgen exposure for the infant. Phthalates and phenols have been identified as endocrine disrupting chemicals. To study the association between prenatal exposure to phthalates, bisphenol A (BPA) and triclosan (TCS) and AGD and the 2D:4D digit ratios. Single spot urine samples were collected in the first trimester from the MIREC Study and analyzed for phthalates and phenols. Anogenital distance (n = 394) at birth and 2D:4D digit ratios (n = 420) at 6 months were measured in male and female infants. Associations between maternal concentrations of phenols and phthalate metabolites and these outcomes were estimated using multiple linear regression models. In females, the anoclitoris distance (ACD) was negatively associated with mono-benzyl phthalate (MBzP) (β = -1.24; 95% CI -1.91, -0.57) and positively associated with mono-ethyl phthalate (MEP) (β = 0.65; 95% CI 0.12, 1.18) (masculinizing). In males, anopenile distance (APD) was positively associated with mono-n-butyl phthalate (MnBP) (β = 1.17; 95% CI 0.02, 2.32) and the molar sum of low molecular weight phthalates (ΣLMW). Female 2D:4D of the right hand was positively associated with MnBP and negatively with total BPA (masculinizing). Significant associations were only observed for the long AGD metrics. Positive associations were observed between MnBP or LMW phthalates and APD in males. In females, prenatal MEP was associated with a masculinizing effect on ACD, while MBzP was associated with a feminizing effect. No significant associations were observed between prenatal phenols and AGD. Given the paucity of research on digit ratios and prenatal chemical exposures, it is difficult to say whether this metric will be a useful marker of prenatal androgen or anti-androgen exposure. Given the large number of associations examined, the statistical associations observed may have been due to Type 1 error. The inconsistencies in results between studies suggest that this issue is yet to be resolved.

Arbuckle TE ，Agarwal A ，MacPherson SH ，Fraser WD ，Sathyanarayana S ，Ramsay T ，Dodds L ，Muckle G ，Fisher M ，Foster W ，Walker M ，Monnier P ... -  《-》

Exposure to Bisphenol A and Phthalates during Pregnancy and Ultrasound Measures of Fetal Growth in the INMA-Sabadell Cohort.

Casas M ，Valvi D ，Ballesteros-Gomez A ，Gascon M ，Fernández MF ，Garcia-Esteban R ，Iñiguez C ，Martínez D ，Murcia M ，Monfort N ，Luque N ，Rubio S ，Ventura R ，Sunyer J ，Vrijheid M ... -  《-》

Early-Life Exposure to a Mixture of Phenols and Phthalates in Relation to Child Social Behavior: Applying an Evidence-Based Prioritization to a Cohort with Improved Exposure Assessment.

Mustieles V ，Rolland M ，Pin I ，Thomsen C ，Sakhi AK ，Sabaredzovic A ，Muckle G ，Guichardet K ，Slama R ，Philippat C ... -  《-》

Impact of exposure to phenols during early pregnancy on birth weight in two Canadian cohort studies subject to measurement errors.

It is of interest to know whether early pregnancy exposure to phenols such as bisphenol-A (BPA) or triclosan (TCS) negatively impacts birth weight outcomes. Exposure to these chemicals is widespread in the Canadian population but obtaining accurate measurements of average exposure is difficult because these chemicals are rapidly excreted from the body, causing body levels to fluctuate both within and between days, as observed in a recent Canadian study (P4). This measurement error can attenuate the estimated effects of exposures. Data from two Canadian cohort studies, the Plastics and Personal-care Products use in Pregnancy (P4) Study and the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, such that all participants with complete BPA or TCS exposure and outcome data were used (MIREC n = 1822, P4 n = 68). We used regression calibration to correct for the attenuating effects of exposure measurement error when modeling the effect of first trimester BPA or TCS exposure on four birth weight outcomes: birth weight (BW), low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA). Specific gravity, time of day, and time since last urine void were also controlled in the analysis. TCS exposure has a marginally significant association with SGA only with odds ratio 0.87 and 95% confidence interval (0.74, 1.00). It also has a marginally significant association with LGA in male offspring with odds ratio 1.11 and 95% confidence interval (1.00, 1.25). The effects of BPA on the four birth outcomes were insignificant. Increased TCS exposure during pregnancy is marginally associated with decreased odds of having SGA offspring. It is possibly associated with decreased BW in males and decreased odds of LBW, though these associations were not present in measurement error corrected models. TCS is possibly associated with increased odds in male offspring of being LGA, though this relationship was not present in models not corrected for measurement error. The study finds no significant effects of BPA on birth weight outcomes, which may be due to more severe measurement error in a single observation of BPA.

Lester F ，Arbuckle TE ，Peng Y ，McIsaac MA ... -  《-》

Association of Prenatal Urinary Concentrations of Phthalates and Bisphenol A and Pubertal Timing in Boys and Girls.

Berger K ，Eskenazi B ，Kogut K ，Parra K ，Lustig RH ，Greenspan LC ，Holland N ，Calafat AM ，Ye X ，Harley KG ... -  《-》