Estimating Average Daily Exposure to Disinfection By-Products in Drinking Water by Examining Alternate Ingestion Pathways

摘要

Several toxicological and epidemiological studies have established a relationship between disinfection by-products (DBPs) in tap water and human health outcomesrnincluding cancer and adverse reproductive outcomes. DBP exposure is multi-route and its degree will vary according to individuals’ water use habits and location of consumers’taps within the distribution system. Because DBPs can be ingested from a variety ofrnsources including directly as tap water, from filtered water and bottled water, or in prepared beverages and food, a more thorough investigation of home filtration systems, bottled water, and water preparation is necessary for more accurate exposure assignment.rnThis study examined bottled water brands consumed and filtration systems employed by a cohort of women enrolled in a study linking tap water and reproductive outcomes. Four different filtration units were evaluated in a home serviced by the same municipal water as the cohort. Each filter removed greater than 80% of trihalomethanes (THMs) at all times when used according to manufacturers’ direction. However, some filters only removed between 30 and 60% of total organic halides (TOX) and haloacetic acids (HAAs). The HAAs and THMs consumed from filtered water can account for 50% of a consumer’s exposure through the ingestion pathway.