Nitrosamines and Nitrosamides

TABLE 4. Transformation of Golden Syrian Hamster Embryo Cells by Nitrosamines and 

Chemical Reported activity T arget culture Hamster cell transformation LTD (Mg/ml) HOT (Mg/ml) Bacterial mutagenesis 

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The class of Il-nitroso compounds (l e , nitrosamines and nitrosamides) is currently considered a unique group that includes members with remarkable carcinogenic properties. Because of their potency and almost ubiquitous presence in... 

Mirvish (53,54) discovered that vitamin C could inhibit ni-trosation reactions. The purely chemical interaction of ascorbic acid with nitrite has been studied for theoretical reasons and because of its importance in the preservation of foods. This interaction has received increased attention for minimizing the presence of nitrosamines and nitrosamides in the environment, and especially in foods. We have studied the relationship in gastric carcinogenesis between high levels of nitrite, including pickling, and of vitamin C as a protective and inhibiting element. 

The nitrosamines and nitrosamides are an important class of chemicals since a large number have been found to be carcinogenic. Nitrosamines require metabolic activation by target tissue microsomal mixed-function oxidases. 

IV. Formation of the N-N bond by exchange 1. Preparation of nitrosamines and nitrosamides... 

Figure 1 Nitrosamines and nitrosamides. Some examples of interest.

Thanks to its characteristics colourless and odourless, easily soluble in water and alcohol, low toxicity, good skin compatibility, broad effective spectrum , Bronopol is being used on a large scale as a preservative for cosmetics and pharmaceuticals (concentrations 0 01-01%). It is listed in the EC list of preservatives allowed for the in-can protection of cosmetics (max. authorized concentration 01% limitations and requirements avoid formation of nitrosamines). Since it is in acidic solutions that Bronopol features the highest stability, weakly acidic media are the ideal field of application. In neutral or weakly alkaline formulations there is a risk that Bronopol releases nitrite (see above) which, with defined amines and amides, forms nitrosamines and nitrosamides which are regarded as carcinogens. 

Nitrosamines and nitrosamides are powerful carcinogens. They are obtained from secondary... 

L. Pasternak, Untersuchung iiber die mutagene Wirkung verschiedener Nitrosamin- and Nitrosamid-Verbindungen, Arzneimittelforschung 14, 802-804 (1964). 

The nitrosamines and nitrosamides, for example, are highly carcinogenic derivatives, and in vivo they are metabolized to diazoalkane or alkyl carbonium ions, both of which will react with DNA (Fig. 13). The highly carcinogenic aromatic... 

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