Profiles, variability and predictors of concentrations of blood trihalomethanes and urinary haloacetic acids along pregnancy among 1760 Chinese women.

Blood trihalomethanes (THMs) and urinary haloacetic acids (HAAs) are the leading candidate biomarkers for disinfection byproduct (DBP) exposure. However, no studies have assessed the exposure profiles, temporal variability, and potential predictors of these biomarkers during pregnancy. Here we collected blood (n = 4304) and urine samples (n = 4165) from 1760 Chinese pregnant women during early, mid-, and late pregnancy, which were separately analyzed for 4 THMs and 2 HAAs.

First-trimester blood concentrations of drinking water trihalomethanes and neonatal neurobehavioral development in a Chinese birth cohort.

Toxicological evidence indicates that exposure to drinking water trihalomethanes (THMs) can impair neural development. However, no epidemiologic study to date has evaluated the relation of trihalomethanes exposure with neonatal neurobehavioral development. Here we aimed to evaluate if prenatal exposure to THMs during early pregnancy is associated with neonatal neurobehavioral development in 451 Chinese mother-child pairs.

Prenatal phthalate exposure, birth outcomes and DNA methylation of Alu and LINE-1 repetitive elements: A pilot study in China.

Background: Epigenetic mechanisms, such as altered DNA methylation, may participate in the relationship between prenatal phthalate exposure and adverse birth outcomes.

Objective: To explore the mediation effect of DNA methylation in the associations of phthalate exposure before delivery with birth outcomes in a Chinese cohort.

Methods: Eight phthalate metabolites in maternal urine before delivery and DNA methylation of Alu and long interspersed nucleotide elements (LINE-1) in cord blood were determined among 106 mother-infant pairs.

Variability and exposure classification of urinary levels of non-essential metals aluminum, antimony, barium, thallium, tungsten and uranium in healthy adult men.

Arsenic, cadmium and lead are well-known toxic metals, and there are substantial studies on variability of these metals in urine to optimize design of exposure assessment. For urinary levels of other nonessential metals such as aluminum (Al), antimony (Sb), barium (Ba), thallium (Tl), tungsten (W) and uranium (U), however, their within-individual and between-individual variability are unclear. Therefore, we collected 529 samples from 11 healthy adult men on 8 days during a 3-month period.

Prenatal urinary polycyclic aromatic hydrocarbon metabolites, global DNA methylation in cord blood, and birth outcomes: A cohort study in China.

Background: Prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) is a potential risk factor for adverse birth outcomes. Epigenetic mechanisms may play a key role in which PAHs exert its effects.

Objective: Our study aimed to examine whether prenatal PAH exposure was associated with adverse birth outcomes and altered DNA methylation and to explore potential mediating roles of DNA methylation.

Predictors and correlations of phthalate metabolite concentrations in urine and seminal plasma among reproductive-aged men.

Background: Certain phthalates are suspected to be endocrine disruptors that are adversely associated with male reproductive health. However, the predictors and correlations of phthalate metabolite concentrations in urine and seminal plasma among reproductive-aged men have not been thoroughly studied.

Objective: To investigate the predictors and correlations of phthalate metabolite concentrations in urine and seminal plasma among adult Chinese males.

Repeated measures of urinary polycyclic aromatic hydrocarbon metabolites in relation to altered reproductive hormones: A cross-sectional study in China.

Background: Polycyclic aromatic hydrocarbons (PAHs) are a group of ubiquitous environmental pollutants. In vivo and in vitro studies have demonstrated that PAHs can alter endocrine function, yet evidence from human studies is limited.

Objectives: The objective of this study was to investigate whether environmental exposure to PAHs was associated with altered reproductive hormone levels, using repeated measures of urinary OH-PAHs as biomarkers.