Mary Grunstra

Haloacetic acids (HAA’s), including 2,2-dichloropropanoic acid, bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid, dibromoacetic acid, dichloroacetic acid, iodoacetic acid, monobromoacetic acid, monochloroacetic acid, tribromoacetic acid, trichloroacetic acid, and total haloacetic acids (HAA5), are a group of disinfection byproducts that can be found in drinking water in minute concentrations. HAA’s are formed when raw water containing high concentrations of organic matter is disinfected via chlorination or chloramination. While epidemiological research on HAA’s and human health is still developing, many HAA’s are widely recognized as probable human carcinogens.
Numerous jurisdictions, including the United States Environmental Protection Agency, the World Health Organization and Health Canada, have either established regulations or proposed guidelines for maximum HAA concentrations in drinking water. Ontario, however, has not yet established any permanent or interim maximum allowable concentration to limit HAA’s in public drinking water.
Using data obtained from the Drinking Water Surveillance Program (Ontario Ministry of the Environment), wherein HAA’s have been monitored at approximately 250 drinking water systems throughout the province between 1995 and 2013, this analysis explores the extent to which HAA’s are found in drinking water systems in treated and distribution water samples. The identification of sites and parameters of concern ensues.
This analysis will next evaluate relationships between hydrological characteristics, exogenous landscape variables, and HAA concentrations; examining in particular nonstationary relationships between HAA prevalence, dissolved organic carbon in water samples, and sample turbidity by employing geographically weighted regression and other nonparametric statistical tests.