CONFIRMATION OF LOW MU-G-KG AMOUNTS OF VOLATILE N-NITROSAMINES IN FOODS BY LOW RESOLUTION MASS-SPECTROMETRY

Abstract

Volatile N-nitrosamines were confirmed in foods at concentrations of less than 10 .mu.g/kg by full scan low resolution mass spectrometry. Ground samples were vacuum-distilled from mineral oil and condensed in liquid nitrogen-cooled vapor traps. The thawed distillate was extracted, the extract was cleaned up and concentrated, and the N-nitrosamine content was determined by combined gas chromatography-thermal energy analysis. Positive samples were further cleaned up, trapped from a gas chromatographic column and purged into a gas chromatograph-mass spectrometer for qualitative confirmation by full scan low resolution mass spectrometry. This procedure was applied to foods spiked at 1 .mu.g/kg and to fried commercial bacons with volatile N-nitrosamine contents of 2-5 .mu.g/kg.