Diethylnitrosamine and Other N-Nitrosamines in Foods

Dimethyl-, diethyl-, di-n-propyl, and other nitrosamines in foods are determined semiquantitatively as follows: (a) initial extraction of the nitrosamines from foods into suitable solvents, (b) isolation of the nitrosamines from other interfering materials by steam distillation and ion exchange cleanup, (c) detection and semiquantitative estimation by TLC, and (d) final identification by GLC analysis of the separated compounds. The detection limit for dimethylnitrosamine in foods was 0.15 ppm and for diethyl- and di-re-propylnitrosamines, 50 ppb. The method has been successfully applied to wheat flour, fish, cheese, and spinach samples.