THE EFFICIENT DEGRADATION OF SELECTED PAHs IN SOIL WITH A SUBSTRATE REFUSE FROM PLEUROTUS OSTREATUS CULTIVATION.

The aim of the study was to assess the degradation rate of selected PAHs (fluoranthene, anthracene, phenanthrene and pyrene) with a refuse from a large-scale production of oyster mushroom (Pleurotus ostreatus). In a 12-week experiment two kinds of substrates were used, i.e. substrate overgrown with mycelium and spent mushroom compost collected after fruiting. Substrates were added at 5, 10 and 20% to the soil artificially contaminated with 2000, 5000 and 10000 μg kg^-1 DW. The time of incubation, PAHs concentration and the percentage of the substrate/compost significantly differentiated the degradation rate of the PAHs. The increase of PAH concentration led to reduction in degradation rate, in particular between 5000 and 10000 μg kg^-1 and at 5% of substrate (or compost). However, application of 10 and 20% substrate (or compost) positively influenced the PAHs degradation at the lowest concentration of PAHs. The strongest increase was observed between 5 and 10% of added substrate (or compost). The degradation of PAHs with compost was slightly weaker than with substrate. The best degradable PAH was phenanthrene (25 and 59%), while pyrene was the weakest degradable (12 and 48%). [ABSTRACT FROM AUTHOR]