Evaluation of urinary mutagenicity in azo dye manufacture workers.

OBJECTIVES The aim of the study was to evaluate urinary mutagenicity in workers employed in a major chemical plant located near Rouen (France) that produces dichlorobenzidine and azo dyes. MATERIALS AND METHODS Samples were obtained from 47 male workers aged 38.9+/-11.3 years (range, 21-58 years), mean duration of employment 9.0+/-8.7 years (range, 1-32 years) for urinary mutagenicity determination with use of the Ames fluctuation test (strains TA 98 and TA 100 with and without metabolic activation) and gas chromatography/mass spectrometry. To assess occupational exposure of workers, urine samples were collected in two series. First, initial just after a one-month holiday (non-exposure). Second, four months later during regular occupational activity. During the same periods, workers completed a questionnaire, which sought information concerning their working conditions, non-occupational factors, and personal habits. RESULTS Of the total 47 samples tested, 3 (6%) collected just after a one-month holiday and 6 (12%) samples collected during regular occupational activity were positive in at least one mutagenicity assay. Dichlorobenzidine traces ranging from 1.6 to 8.9 ppb were detected in 4 (8%) samples of the exposed as well as in 4 (8%) samples of non-exposed workers. No significant differences between biological and analytical responses obtained in the non-exposure period and after occupational exposure were observed, however, 5 (11%) workers in this group presented urinary mutagenicity that could be related to occupational exposure. CONCLUSIONS The study suggests that some industrial hygiene problems, revealed in the analysis of questionnaire responses and confirmed by our evaluation, could be undoubtedly and easily solved to improve working conditions of the employees.