GENOTOXICITY STUDIES ON PROFESSIONAL HAIR COLORISTS EXPOSED TO OXIDATION HAIR-DYES

The cytogenic repercussions of occupational exposure to oxidation hair dyes were assessed by using three assays in professional hair coloris ts. The assays were sister chromatid exchanges (SCE) in circulating ly mphocytes to evaluate the interchange of DNA replication products at a pparently homologous chromosomal loci, single cell gel electrophoretic (SCGE) assay to detect the presence of DNA strand breaks/alkali-labil e damage, and the Ames assay using Salmonella typhimurium strain TA98 to detect the urine mutagenicity. The ability of these assays to detec t genetic damage caused by oxidation hair dyes in man compared with cl osely matched controls produced the following findings. (i) The SCE as say could not detect the mutagenic effect in lymphocytes of exposed su bjects from whom complete data were obtained. However, subjects (contr ols and exposed) with a history of smoking had slightly increased SCEs than the non-smokers in both groups. (ii) The extent of DNA migration (SCGE assay) did not distinguish between the samples in either the ex posed or control subjects. Like the SCE results, the exposed and contr ol smoker subjects showed a greater proportion of damaged lymphocytes with apparent migration of DNA. (iii) No clear differences in the muta genic activity of the urine samples were observed between the exposed and control subjects. But, pooling exposed and controls together, a po sitive and significant variation in the urinary mutagenic effect was o bserved with the number of cigarettes smoked per day. (C) 1997 Elsevie r Science B.V.