Abstract
Soil pollution by toxic chemicals has become one of important environmental issues. As a soil pollution-control measures of organic toxicants, bioremediation method is considered to be useful.
In this study, white rot fungus Phanerochaete chrysosporium was used as a test organism for bioremediation. As this fungus can not survive in soils alone, it was cultured in sawdust and was spiked to the test soil with pentachlorophenol (PCP). Pentachloroanisole (PCA) was determined as an intermediary product. The ecotoxicity of PCP and PCA was evaluated by bioassay using higher plant (Lactuca sativa) and alga (Selenastrum capricornutum). The toxicity of PCA was lower than PCP. The soil-sawdust mixture inoculated with fungus was administrated with nutrients, the nutrients were decomposed and ammonium was produced. Because the interstitial water was alkalized and the pH value went up, the PCP solubility of water extract solution increased. Therefore the PCP concentration in water extract solution from the soil-sawdust mixture inoculated with fungus was higher than that from the non-inoculated soil-sawdust mixture. The toxicity of decomposed products and various environmental factors in soils should be considered, when bioremediation method is used for pollution-control of organic toxicants on site.
