Urinary brominated trihalomethanes among pregnant women: Correlation with lifestyle factors

Abstract According to the epidemiological evidences, long-term exposure to trihalomethanes containing bromine (Br-THMs) is associated with a variety of unpleasant consequences such as congenital malformations, preterm delivery, changing in gestational age, fetal growth and death, etc. The objective of current work was to monitor Br-THMs concentration in the pregnant women’s urine samples, to understand relationship between Br-THMs concentration and sociodemographic and water-use behavior as lifestyle factors. In this study, 118 third-trimester pregnant women, who cooperated in the Persian Birth Cohort, were studied. The concentration distribution of urine samples that were measured by a gas chromatography-mass spectrometer (GC-MC) had a positive deviation that was exposed to logarithmic transformation. By utilization of independent samples of t test, one-way ANOVA, Spearman ranks correlation coefficient, and multivariable linear regression, relationship between Br-THMs concentrations of urine with demographic and lifestyle factors was evaluated. According to the results, mean concentrations (standard deviation) of Br-THMs including bromodichloromethane (BDCM), dibromochloromethane (DBCM), and total bromoform (TBM) were recorded as 30.17 (40.80), 10.25 (11.37), 14.76 (27.17), and 4.96 (3.21) ng/L, respectively. The regression model predicted significant increase in relationship between time of washing clothes by hand and the concentration of Br-THMs. In the analysis of the relationship between using storage tanks as a source of drinking water and the contaminants, according to different statistical methods, inverse meaningful correlation relationship was found.