The Relationship Between Exposure To Trihalomethanes And Haloacetic Acids In Drinking Water During Pregnancy And Term Birth Weight In A Multi-Ethnic Cohort In The UK

Background and Aims: Evidence for a relationship between trihalomethane (THM) or haloacetic acid (HAA) exposure and birth weight is inconsistent. THMs and HAAs have typically been examined as separate exposures, however disinfection by-products occur as mixtures in drinking water supplies. We have investigated maternal joint exposure to THMs and HAAs, incorporating individual water use into exposure assessment, in relation to birth weight in a multi-ethnic birth cohort in the UK. Methods: Pregnant women reported their water consumption and activities via questionnaire at 28 weeks gestation. Monthly THM and quarterly HAA concentrations were modelled at water supply zone level, and combined with mother's water use to calculate integrated uptake of THMs into blood (via consumption, showering, bathing and swimming) and HAA ingestion via consumption. Using multiple linear regression, we examined the relationship between THM and HAA exposures and term birth weight for approximately 7,500 babies, stratified by e...