Successive rapid reductive dehalogenation and mineralization of pentachlorophenol by the indigenous microflora of farmyard manure compost.
OBJECTIVE
To determine whether composting with animal manure can be used to effectively remediate soil from a pentachlorophenol (PCP)-contaminated site, and to establish the fate of the degraded xenobiotic.


RESULTS
Contaminated soil from a sawmill site was mixed with farm animal manure and composted in a 0.5 m3 silo under fully aerobic conditions. The disappearance and fate of PCP was monitored by gas chromatography (GC-ECD) and extensive mineralization confirmed in experiments with 14C-radiolabelled PCP. The disappearance of PCP was rapid and virtually complete within 6 days, prior to the onset of thermophilic conditions. Dechlorination of the PCP was found to be both reductive and sequential.


CONCLUSIONS
PCP removal from contaminated soil by aerobic composting with animal manure is efficient and proceeds via reductive dechlorination to virtually complete mineralization. This contrasts with other chlorophenol composting regimes in which mineralization is achieved but dechlorination intermediates do not accumulate to detectable levels.


CONCLUSIONS
The results of this study demonstrate that anaerobic reductive dechlorination can proceed in an aerobic composting environment and contribute to efficient pentachlorophenol removal. Farmyard manure composts may represent a rapid, low-cost, low-technology option for treatment of chlorophenol-contaminated soils.
Jaspers
C J
CJ
Section Interfacultaire d'Agronomie, Laboratoire de Physiologie et Ecologie Microbienne, Université Libre de Bruxelles, Brussels, Belgium.
Ewbank
G
G
McCarthy
A J
AJ
Penninckx
M J
MJ
D000383:Agriculture; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002713:Chlorine / Q000378:metabolism; D008372:Manure / Q000382:microbiology*; D010084:Oxidation-Reduction; D010416:Pentachlorophenol / Q000378:metabolism*; D012037:Refuse Disposal; D012989:Soil Pollutants / Q000378:metabolism*; D013997:Time Factors
D008372:Manure; D012989:Soil Pollutants; D002713:Chlorine; D010416:Pentachlorophenol