Metal toxicity effects the biological treatment of aqueous metal wastes: Is a biocatalytic system feasible for the treatment of wastes containing actinides?

Abstract

The toxicities of uranyl and vanadyl ions and of tri-and tetravalent cations towards the activity of a Citrobacter phosphatase were investigated. The oxycations were inhibitory, but uranyl ion inhibition was overcome in the presence of excess organic phosphate substrate. Precipitation of uranyl ion with liberated inorganic phosphate was implicated as a detoxification mechanism which was substantiated using immobilized cells in a flow-through bioreactor. Application of these studies to the design of a process to treat actinide-bearing aqueous wastes is discussed.

Microbial Influence on the Performance of Subsurface, Salt-Based Radioactive Waste Repositories

“…Apart from the ligands produced as waste metabolites, microorganisms can generate other organic and inorganic ligands. Bacterial mineralisation of uranium via phosphate, as a detoxification mechanism, may result in precipitation and impede migration (Plummer and Macaskie, 1990;Tolley et al, 1992). Phosphate may also serve as a "nucleation focus" on cell surfaces (Lloyd and Macaskie, 2002).…”

Biosorption technology: starting up an enterprise

“…Heavy metals (e.g., lead, copper, cadmium, zinc, chromium, etc. ) are toxic even at low concentrations (Tolley et al, 1992). As they are non-biodegradable, their threat is multiplied by their accumulation in the environment through the food chain.…”

The Distribution of Toxic and Essential Metals in the Florida Everglades

“…In addition, the excess of Pb may also inhibit enzyme activities and alter mineral nutrition (Sharma and Sohn 2009). Cadmium is another well-studied toxic metal (Tolley et al 1992;Su et al 2009). …”