Three chlorinated compounds, namely, Pentachlorophenol(PCP), Hexachlorobenzene (HCB), and Carbon tetrachloride were biodegraded under anaerobic conditions using a (CCl4)mixed culture obtained from an anaerobic sewage sludge digestor in Linden, NJ.
Three sets of cultures capable of degrading each of the target compounds were established. Primary Enrichment Cultures (PECs) from the anaerobic sludge were exposed to each one of the target compounds. The cultures were able to degrade each target compound as follows: HCB, 0 to 1.2 ppm; PCP from 0 to 3-4 PPM; CCl4, 0.5 to 15.5 PPM
One culture from each PEC group (CCl4, HCB, PCP) was transferred into fresh sterilized sludge with a mixture of all three compounds at a concentration of approximately 10 PPM each. Each culture produced some degradation: HCB 0.27 to 0.5 PPM; PCP, 1.7 to 6.3 PPM; and CCl4, 2.4 to 5 PPM The maximum time period for degradation in both experiments was approximately three months.
This is the first time in the literature that these three chlorinated compounds have been anaerobically biodegraded at the same time.
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