Complex Approach to Evaluating Genotoxicity from Occupational Factors in Coal Mining Industry

The level of cytogenetic damage was analyzed in coal miners (N = 116) and the control sample (N = 169) using an assay for scoring of chromosomal aberrations (CAs) and the DNA comet assay in lymphocytes, as well as the micronucleus test in buccal epithelial cells (MN in BEC). The group of coal miners was characterized by a statistically significantly increase in the main index values of the used test system, compared to the control group. Specifically, the level of chromosomal aberrations in the miner and control groups was 4.69 +/- 0.28 and 2.13 +/- 0.10%; the proportion of DNA in the comet tail was 4.33 +/- 0.38 and 2.16 +/- 0.24%; and the micronucleus level was 1.44 +/- 0.21 and 0.23 +/- 0.12 parts per thousand, respectively (P < 0.05). Moreover, in the sample of coal miners, a considerable increase in the levels of additional test indices was observed. For CAs, these parameters included the frequency of single fragments, chromatid-type aberrations, paired fragments, dicentrics without fragments, chromosome exchanges, and chromosome-type aberrations; for the DNA comet assay, these were the comet tail moment and Olive tail moment; for the MN in BEC, the frequencies of binucleated cells, cells with notched nuclei, geminate nuclei, karyorhexis, and apoptotic bodies. Ranking of the results according to major cytogenetic abnormalities made it possible to establish that, in the group of miners, the proportion of individuals with the index values above the background was 68.97% for CAs, 52.13% for the DNA comet assay, and 36.08% for the MN in BEC. The proportion of individuals with cytogenetic damage higher than the background simultaneously in three test systems was 20% of the total sample of miners. To assess the mutagenic effects from occupational factors of coal mining enterprises, it seems reasonable to use a complex of test systems (CA test, DNA comet assay, and MN in BEC).