Nitrosamine Entstehung, Belastung des Menschen und mögliche biologische Auswirkungen.

Since a relation between exposure to nitrosamines and development of cancer in man is highly probable, human exposure should be kept as low as possible. Therefore it is necessary to understand the mechanisms of nitrosation and to have approximate data about the intensity of N-nitroso-compound exposure in the external and internal human environment. Nitrosamines are formed from various precursors especially nitrate, nitrite, and secondary and tertiary amines, which all are ubiquitous. They can be formed exogenously and endogeneously, i.e. externally and in vivo in the human body. Exposure with exogenously formed nitrosamines occurs by ingestion, inhalation, or by absorption through the skin. The endogenous formation of nitrosamines is especially supported by the acid pH of the stomach. To answer the question if and which nitrosamines initiate or promote cancer in humans, it is necessary to carry out specific investigations with exposed person groups