Contamination of Chinese salted fish with volatile N-nitrosamines as determined by QuEChERS and gas chromatography-tandem mass spectrometry.

The QuEChERS sample preparation method and gas chromatography-tandem mass spectrometry were employed to determine nine volatile N-nitrosamines (VNAs) in Chinese salted fish. This method was validated by considering calibration plot linearity, selectivity, matrix effects, trueness, precision, limits of quantification and specificity. Fifty-four samples of Chinese salted fish obtained from five provinces were analyzed. The results indicated that the concentrations of one VNA, N-nitrosodimethylamine in 57.4% of the samples exceeded the acceptable limit (the China national standard value of 4μgkg