Baud-Grasset S, Baud-Grasset F, Bifulco J M, Meier J R, Ma T H
International Technologies Corporation, Cincinnati, OH 45246.
Mutat Res. 1993 Oct;303(2):77-82. doi: 10.1016/0165-7992(93)90098-g.
The fungal degradation of polyaromatic hydrocarbons (PAH) in a contaminated soil from a hazardous waste site was evaluated in a pilot-scale study. As some PAH are known to be mutagens, the Tradescantia-micronucleus test (TRAD-MCN) was selected to evaluate the genotoxicity of the soil before and after fungal treatment. The genotoxicity test was conducted with Tradescantia clone 4430. Cuttings were exposed for 30 h to different dilutions of soil extracts from the PAH-contaminated soil before and after fungal treatment. Soil extracts before fungal treatment exhibited a relatively strong genotoxic effect in the meiotic pollen mother cells even at a 1% concentration, and the highest concentration without significant effect was 0.25%. After fungal treatment, the depletion of selected PAH was associated with a reduction of the soil genotoxicity. The 2% concentration of the extract from the fungal-treated soil showed genotoxic effects comparable to the 1% soil extract without fungal treatment. These results indicate that the Trad-MCN test has a potential utility for evaluating the efficiency of bioremediation of genotoxic soil contaminants.