Microbial Degradation of Selected Hazardous Materials: Pentachlorophenol, Hexachlorocyclopentadiene, and Methyl Parathion

摘要

This program evaluated the use of selected pure culture microrganisms for potential in biodegrading the hazardous materials pentachlorophenol (PCP), hexachlorocyclopentadiene (HCCP), and methyl parathion (MP). Each chemical was separately challenged by each of 24 organisms in aqueous medium under aerobic conditions. Following the initial screening and selection process, pure culture organisms identified as having potential for biodegradation of the selected chemicals were subjected to further testing and evaluation. Although no fully conclusive evidence of biodegradation of these substances was obtained, data indicated that a number of fungi have potential for disposal of PCP, HCCP, and MP. One bacterial culture demonstrated tolerance to PCP at 200 ppm in soil and appeared to reduce the PCP concentration in an aqueous medium when dextrose was provided. This isolate may have potential for removal of PCP from spill-contaminated areas. A fungus also showed some potential for degrading PCP. Time constraints and budgetary requirements precluded the use of C-14-labeled chemicals and the extensive analyses required for isolation, identification, and quantification of potential by-products and metabolities of the biodegradation or biotransformation of the selected chemicals. Improvements on existing HPLC and GC-EC methods were developed.