ENVIRONMENTAL GENOTOXICITY IN AN ESTONIAN OIL-SHALE INDUSTRIAL-AREA

The genotoxicity of environmental samples (ambient air, drinking and r iver waters, purified waste water and oil shale ash) from an oil shale mining and processing area was studied by using the Ames Salmonella/m icrosome assay. Salmonella typhimurium strains TA98 and YG1021 were us ed, with and without metabolic activation with rat liver homogenate S9 . The water samples were treated with amberlite adsorbent XAD-S for co ncentrating non-polar compounds. The air samples were collected on gla ss fibre filters by using a high volume air sampler, and extracted wit h dichloromethane by using a Soxhlet apparatus. The air samples were m utagenic in both strains, both with and without SS-mix. The air mutage nicity data were compared with data from similar tests on cigarette sm oke condensate as a positive control. Based on the fact that the avera ge 8-hour respiratory volume at occupational activities is between 10m (3) and 20m(3), the load of airborne mutagenicity at the cokery plant during one week was estimated to be equal to the mutagenicity produced by the mainstream smoke of one cigarette. The drinking and river wate r samples were tested with both strains, but no dose-related increases in water counts per plate were noted. The oil shale ash sample showed no mutagenic activity, but showed cytotoxicity at the higher doses te sted.