You are here:
IDENTIFICATION OF CHLORINE DIOXIDE AND CHLORAMINE DRINKING WATER DISINFECTION BY-PRODUCTS
Citation:
Richardson, S D., A D. Thruston Jr., C. RavAcha, AND V. Glezer. IDENTIFICATION OF CHLORINE DIOXIDE AND CHLORAMINE DRINKING WATER DISINFECTION BY-PRODUCTS. Presented at International Society of Exposure Analysis Conference, Monterey, CA, October 24-27, 2000.
Impact/Purpose:
(1) Use toxicity-based approach to identify DBPs that show the greatest toxic response. (2) Comprehensively identify DBPs formed by different disinfectant regimes for the 'Four Lab Study'. (3) Determine the mechanisms of formation for potentially hazardous bromonitromethane DBPs.
Description:
Due to concern over the potential adverse health effects of trihalomethanes (THMs) and other chlorinated by-products in chlorinated drinking water, alternative disinfection methods are being explored. Chlorine dioxide and chloramine are two popular alternative disinfectants, with hundreds of drinking water treatment plants currently using these disinfectants in the U.S. However, there is little known about the disinfection by-products (DBPs) that are produced from these alternative disinfectants. Another important factor is the effect of elevated bromide levels on the formation of DBPs. Bromide is important because it has caused the formation of hazardous bromine-containing DBPs for other disinfectants studied (chlorine and ozone). To investigate the effect on the effect of elevated bromide levels on the formation of chlorine dioxide DBPs, drinking water from Israel was chosen for study, due to their extremely high natural bromide levels (2-3 mg/L). Chlorine dioxide-treated drinking water was collected from two full-scale plants in Israel. To investigate the formation of chloramine DBPs, drinking water was collected from a full-scale plant in Denver, CO, which uses chloramine as its primary disinfectant. High and low resolution gas chromatography/mass spectrometry (GC/MS) (electron ionization and chemical ionization) and liquid chromatography (LC)/MS were used to identify DBPs. Rather than targeting a small group of pre-selected DBPs, we attempted to identify every compound that was detected. In the chlorine dioxide-treated water from Israel, many bromine-containing compounds were identified, including some unusual bromo-aromatic compounds. A DBP of particular interest was 1,1,3,3-tetrabromopropanone. Its chlorinated analog--1,1,3,3-tetrachloropropanone--had been found as one of only two chlorine-containing DBPs identified in a previous chlorine dioxide DBP study in the U.S., where there were not high bromide conditions. In the chloramine-treated drinking water, several halogenated DBPs were found, including some brominated and iodinated compounds.