E. R. Landa T. Kraemer R. Zielinski Elizabeth J.P. Phillips 2001 Scale and sludge deposits formed during oil production can contain elevated levels of Ra, often coprecipitated with barium sulfate (barite). The potential for sulfate-reducing bacteria to release 226 Ra and Ba (a Ra analog) from oil-field barite was evaluated. The concentration of dissolved Ba increased when samples containing pipe scale, tank sludge, or oil-field brine pond sediment were incubated with sulfate-reducing bacteria Desulfovibrio sp., Str LZKI, isolated from an oil-field brine pond. However, Ba release was not stoichiometric with sulfide production in oil-field samples, and <0.1% of the Ba was released. Potential for the release of 226Ra was demonstrated, and the 226 Ra release associated with sulfate-reducing activity was predictable from the amount of Ba released. As with Ba, only a fraction of the 226Ra expected from the amount of sulfide produced was released, and most of the Ra remained associated with the solid material. application/pdf 10.1080/01490450120549 en Taylor & Francis Sulfate-reducing bacteria release barium and radium from naturally occurring radioactive material in oil-field barite article