Volatile N-Nitrosamines in various fish products

N-Nitrosamines (NAs) are a group of carcinogens which have been detected in various fish products. In this study the level of five NAs (N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodibutylamine, N-nitrosopiperidine, and N-nitrosopyrrolidine) was determined in 294 various samples of fish, and in 77 samples of oil during 2001–2005. For the sample cleaning the two-step solid-phase extraction with Extrelut and Florisil sorbents was used. NAs were separated by gas chromatography and detected by positive-ion chemical ionization using ammonia as reagent gas. The HP 6890 Plus GC/HP 5973 MSD was used in the selected ion monitoring mode with pulsed splitless injection. In this work, the limit of detection and the limit of quantitation of NA were approximately 0.10 and 0.35 μg/kg, respectively with about 85%. The sum of the average of five NAs content in cold-smoked fish was found to be 1.92 μg/kg, in hot-smoked fish – 4.36 μg/kg, in fried fish – 8.29 μg/kg, in pickled fish – 5.37 μg/kg, in salted fish – 3.16 μg/kg, in salted/dried fish – 3.81 μg/kg, and in the fresh fish it was not detected.