nitrosamine

Nitrosamines are a class of chemical compounds with the general structure R2N-N=O, in which a nitroso group is bonded to a secondary amine. They are commonly referred to as N-nitrosamines and vary in size and substituents around the nitrogen atom.

Nitrosamines form when nitrosating agents such as nitrous acid react with secondary amines, often under acidic conditions, heat, or during manufacturing or storage. They can occur as contaminants or byproducts in food, drinking water, tobacco smoke, cosmetics, rubber products, and pharmaceuticals.

Health effects: Many nitrosamines are genotoxic and carcinogenic in animals, and several are considered probable carcinogens in humans. Among the best studied are compounds such as N-nitrosodimethylamine (NDMA) and related nitrosamines, which have been linked to cancer risk at certain exposure levels.

Detection and regulation: Analytical methods for nitrosamines include LC-MS/MS and GC-MS. Regulatory authorities set limits and guidelines for nitrosamine levels in foods, water, cosmetics, and drugs, and require testing of products and process controls to minimize formation and contamination.

Prevention and control: To limit formation, reduce the availability of nitrites and secondary amines, and use antioxidants to inhibit nitrosation. Controlling pH, temperature, and storage conditions during processing and storage is important. In pharmaceuticals, clean synthesis, thorough purification, and validated testing help minimize nitrosamine impurities.