Biological monitoring of toluene and DNA polymorphism in humans.

The effects of genetic polymorphism in aldehyde dehydrogenase 2 (ALDH2) on alcohol intakes and toluene metabolism were studied in workers who handle toluene. The genotypes of ALDH2 were divided into three groups, which were the homozygous genotype of normal ALDH2 (NN), the homozygous genotype of an inactive one (DD) and the heterozygous genotype of normal and inactive ones (ND), using the polymerase chain reaction (PCR) method in a solution containing ddGTP. The alcohol intake of the DD group was very small. On the other hand, the alcohol intake of NN group was higher than that of DD group. That of ND group was about half way between those of NN group and DD group. The alteration of toluene metabolism by the polymorphism of ALDH2 was not clear because the exposure levels of the workers to toluene were low.