Nitrosamines and their precursors in some Kazakh foodstuffs

Numerous samples of various foods, such as salt-dried and smoke-dried meats, fermented sausages, sour-milk products, fermented mare's and camel's milk, raw vegetables, rice, rock and table salts, local bread and daily food rations were analysed by GC-TEA and HPLC-TEA for the presence of volatile nitrosamines. Apart from the observation of NDMA (up to 0.7 microgram/kg) in three samples of Kazakh cheeses, the volatile nitrosamines were detected only in some meat and meat products. Salted air-dried meat contained NDMA in amounts up to 54 micrograms/kg. NPYR (12 micrograms/kg) was found in one sample of nitrite-cured sausage. The highest content of NPIP (7 micrograms/kg) was detected in fermented, home-made sausage. It is clear that the only significant contribution of these dialkyl and heterocyclic nitrosamines to the diet is from stored, salt-dried meat and nitrite-cured meat products. Analyses of nitrate and nitrite in various local products are reported. The validity of our assumption that the high incidence of oesophageal cancer can be lowered by realistic improvements in the processing and storage of meat and meat products requires further evaluation.