Comparison of Different Genotoxic Tests for Biological Monitoring of Coke Oven Workers. Preliminary Results

ABSTRACT

Chemical by-products of coke production are classified by IARC as carcinogenic in humans. Polycylic aromatic hydrocarbons (PAH) are the main compounds involved in carcinogenic and mutagenic activities of coke oven smokes, but many other compounds are present in emissions and could be involved in these activities. PAH analysis of the atmosphere indicated external contamination, but is not sufficient to evaluate the risk for exposed workers. The aim of this study was to evaluate relationship between atmospheric analysis of PAH and genotoxic markers in coke oven workers'white cells compared to controls. One hundred fifty-five exposed workers'samples were analyzed. They were selected in 5 coke production sites using a complete questionnaire allowing one to exclude all confounding factors. Two equal groups of smokers and nonsmokers were analysed. Analysis of chromosomal aberrations (CA), sister chromatid exchange (SCE), micronucleus (MN) and DNA-adduct formation using ³²P-postlabelling were performed on leucocytes. Each worker was equiped with an individual pump during the shift, for analysis of 16 PAH.

All markers were strongly modified by smoking habits. In smokers, CA, SCE and MN were not influenced by exposure to PAH. The number of DNA-adducts was increased with PAH concentration. In non smokers, we have observed an increaseof breaks / cells and of the percentage of cells with aberrations. Number of MN and SCE were unchanged. The number and the amount of DNA-adducts were strongly increased in exposed workers. DNA-adducts appear to be the best marker for genotoxic risk assessment.

Key words::

• 32P-postlabelling
• DNA-adducts
• chromosomal aberrations
• methylation
• biomonitoring
• coke oven worker