AWWA ACE58345
Mechanistic Studies of NDMA Formation
Conference Proceeding by American Water Works Association, 06/15/2003
Choi, Junghoon; Valentine, Richard
Full Description
N-nitrosodimethylamine (NDMA) formation by the reaction of dimethylamine(DMA) with nitrite was studied in the absence and in the presence of HOCl at pH 7. Thepresence of HOCl significantly enhanced NDMA formation by nitrite. In the absence ofHOCl, the concentration of NDMA formed by DMA with nitrite was increased from 0.34ug/L to 0.65 ug/L as the nitrite concentration increased from 0.05 mM to 1.0 mM.However, in the presence of HOCl, the formation of NDMA was significantly enhancedfrom 0.14 ug/L to 15.47 ug/L as the nitrite concentration increased from 0.01 mM to 1.0mM. Additional studies in mixtures of 15N and 14N labeled nitrite andammonia indicated that the source of nitrogen in the nitroso group of NDMA may comefrom both ammonia and nitrite but their contribution to NDMA formation is governed bytwo different mechanisms. Includes 5 references, table, figures.