Determination of N-nitrosodimethylamine in drinking water by UPLC-MS/MS

The method for detecting N-nitrosodimethylamine (NDMA) in drinking water using ultra performance liquid chromatography(UPLC) coupled with tandem mass spectrometry (MS/MS) was improved by optimizing the clean-up procedure to remove the matrixinterference in pretreatment process, and was then applied to a survey of NDMA in both raw and finished water samples from fivewater treatment plants in South China. The NDMA concentrations ranged from 4.7 to 15.1 ng/L in raw water samples, and from 4.68to 46.9 ng/L in finished water. The NDMA concentration in raw water was found to be related with nitrite concentration, and duringthe treatment, the NDMA concentration increased following ozonation but decreased after subsequent activated carbon treatment.