Detergents, shampoos can make water carcinogenic

Washington, May 27 (IANS) Certain constituents in shampoo, detergents and other household cleaning agents are likely to turn water from sewage treatment plants carcinogenic.

The study sheds new light on possible environmental sources of this poorly understood water contaminant, called nitrosodimethylamine or NDMA, a semi-volatile organic chemical that is highly toxic and is a suspected human carcinogen.

William Mitch, chemical engineer from Yale University, notes that scientists have known that NDMA and other nitrosamines (chemical compounds produced from nitrates which occur in proteins) can form in small amounts during the disinfection of wastewater and water with chloramine.

Although nitrosamines are found in a wide variety of sources – including processed meats and tobacco smoke – scientists know little about their precursors in water.

Past studies with cosmetics have found that substances called quaternary amines, which are also ingredients in household cleaning agents, may play a role in the formation of nitrosamines.

Their lab research showed that when mixed with chloramine, some household cleaning products – including shampoo, dishwashing detergent and laundry detergent – formed NDMA.

The report notes that sewage treatment plants may remove some of the quaternary amines that form NDMA, said a release of the American Chemical Society (ACS).

However, quaternary amines are used in such large quantities that some still may persist and have a potentially harmful effect on the effluents from sewage treatment plants.

These findings were published in the ACS’ Environmental Science & Technology.