Genetic and individual differences in the process of biotransformation and their relevance for occupational medicine.

Genetically determined differences in biotransformation of xenobiotics have been identified which are important for occupational medicine. This review highlights the following topics: (i) genetic polymorphisms in the activity of cholinesterases; (ii) polymorphisms in the cytochrome P-450 isozymes CYP2D6 and CYP2E1; (iii) polymorphisms in the N-acetyltransferase NAT-2; (iv) polymorphisms in the glutathione-S-transferases mu and theta. From the view-point of occupational medicine, these genetic polymorphisms may affect the toxicity of industrial and workplace chemicals, such as organophosphates (i), major solvents and monomers for plastics (ii), aromatic amines (iii), and compounds like styrene/styrene oxide, methyl halides, dichloromethane and ethylene oxide (iv). Individual differences in biotransformation linked with genetic polymorphisms also have a considerable influence on biological monitoring strategies and on human risk assessment.