MICROBIAL TRANSFORMATION OF POLYCHLORINATED PHENOXY PHENOLS

Abstract

Microbial metabolism of polychlorinated phenoxy phenols (PCPPs) and polychlorinated phenoxy anisoles (PCPAs) was studied in mixed and pure bacterial cultures and in PCPP-contaminated soil. Both in the laboratory and in the field the PCPPs with a hydroxyl group in the para position in the molecule were methylated faster than those with a hydroxyl group in the ortho position. Rhodococcus chlorophenolicus, a polychlorophenol mineralizer, methylated 40% of one PCPP compound in 7 days, given in a concentration of 10ppm. The methylation was aerobic. There was no further metabolism of PCPAs. One of the PCPA-compounds was also o- demethylated by R. chlorophenolicus. In chlorophenol-contaminated soil each of the 8 PCPPs contained in a technical chlorophenol product became methylated.