Nitrosamines are chemical compounds of the chemical structure R1N(-R2)-N=O, that is, a nitroso group bonded to an amine. Most nitrosamines are carcinogenic
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In foods, nitrosamines are produced from nitrites and secondary amines, which often occur in the form of proteins. Their formation can occur only under certain conditions, including strongly acidic conditions such as that of the human stomach. High temperatures, as in frying, can also enhance the formation of nitrosamines.
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These processes lead to significant levels of nitrosamines in many foodstuffs, especially beer, fish, and fish byproducts, and also in meat and cheese products preserved with nitrite pickling salt. The U.S. government established limits on the amount of nitrites used in meat products in order to decrease cancer risk in the population.[5] There are also rules about adding ascorbic acid or related compounds to meat, as the compounds inhibit formation of nitrosamines.
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