Mutagenic Activity of Selected Organic Compounds Treated with Ozone

In the early 1970's it was discovered by several groups of investigators that trihalomethanes (THM) were present in some American drinking water supplies, and that their presence was due primarily to the process of chlorination. Bellar and coworkers (1974) pinpointed the appearance of trihalomethanes to the addition of chlorine in the water treatment process. Symons and coworkers, in the National Organics Reconnaissance Survey (1975), reached the conclusion that treated water contained higher levels of trihalomethanes than untreated water supplies, as surveyed in cities across the United States. In 1978 Glatz and coworkers reported finding increased mutagenic activity in chlorine -treated water in several U.S. cities.