NDMA
Much of the recent discussion about chloramine has focused on NDMA, and it is critical to distinguish between chloramine and NDMA. NDMA can be a byproduct of chloramination or chlorination, but drinking water is not a major source of exposure to NDMA. The biggest sources of human exposure to NDMA are tobacco smoke, chewing tobacco, bacon and other cured meats, beer, fish, cheese, toiletries, shampoos, cleansers, interior air of cars, and household pesticides. In addition, NDMA can form in the stomach during digestion of foods or drugs that contain alkylamines, which are naturally occurring compounds.
At very high levels—100,000 times greater than even the highest levels seen in a recent survey of chlorinated and chloraminated drinking waters—NDMA may cause serious human health problems, such as liver disease. Such effects are seen at concentrations ranging from 5 to 50 parts per million in water; for comparison a study conducted by the California Department of Health Services in 1999 and 2000 found the highest level of NDMA in drinking water that had been treated with chloramine was 0.00006 parts per million. In that study, most of the concentrations of NDMA were far lower than that, and many water samples in the California Department of Health Services study, including those from the San Francisco Public Utilities Commission water system taken in 2000, did not have any detectable concentrations of
Read more about this topic: Chloramination, Adverse Effects