The examination of samples of various commer-cially available vegetable oils (olive oil, sunflower oil, thistle oil, linseed oil, plant germ oil, etc.) and of various samples of margarine for the presence of vola-tile N-nitroso-compounds yielded the following results. By means of the above mentioned procedure (gas liquid chromatography — AFID gas liquid chromatography — TEA), N-nitrosodimethylamine (NDMA) was found to be present in 21 of 61 dif-ferent samples of vegetable oil, in concentrations ranging from < 1 μg/kg to 23 μg/kg. 18 samples con-tained N-nitrosodiethylamine (NDEA) in concentra-tions varying between < 1μg/kg and 27.8 μg/kg. 37 out of 107 different samples of margarine were shown to contain N-nitroso compounds. N-nitroso-dimethylamine was found to be present in 15 samples. The range of concentrations determined was between < 1 μg/kg and 5.8 μg/kg. 33 samples con-tained N-nitrosodiethylamine in concentrations varying between < 1 μg/kg and 7.5 μg/kg.