IMMOBILIZATION OF HEAVY-METALS IN INCINERATOR ASH BY THE ACTIVITY OF DESULFOVIBRIO-DESULFURICANS

The ash produced by the incineration of domestic refuse contains signi ficant amounts of heavy metals. Because incerator ash is often dispose d of by burial in landfills, leaching of the heavy metals into groundw ater is an environmental hazard associated with incineration. Although ash is considered to have the potential to be highly toxic, the anaer obic sulfate reducing bacterium Desulfovibrio desulfuricans can grow i n the presence of incinerator ash and significantly increase the leach resistance of the lead, cadmium, and chromium that is present in the ash. The data suggest that conditions compatible with microbial sulfid ogenesis in landfills may be of value in preventing metal leaching sho uld other containment startegies prove ineffective.