Newly Discovered Bacteria May Gobble Down Hazardous Waste

Bacteria gobble down all kinds of waste, but could they actually deal with nuclear waste? Scientists have found that tiny single-celled organisms that have recently been discovered may just be able to help with nuclear waste disposal.

Getting rid of nuclear waste is extremely challenging. Large volumes of this waste are slated for burial deep underground. The largest volume of radioactive waste, termed "intermediate level," will actually be encased in concrete prior to disposal into underground vaults.

Over time, ground waters can reach these waste materials and react with the cement and become highly alkaline. This change drives a series of chemical reactions that triggers the breakdown of the various "cellulose" based materials that are present in these complex wastes. One of the products linked to these activities is called isosaccharinic acid (ISA). This material is a particular cause for concern since it can react with a wide range of radionuclides, which are unstable toxic elements that are formed during the production of nuclear power and make up the radioactive component of nuclear waste. If ISA binds to radionuclides, then it's possible for them to become soluble and enter drinking water or the food chain.

Yet certain microorganisms may prevent this problem. Researchers have discovered a specialist "extremophile." These bacteria can thrive under the alkaline conditions expected in cement-based radioactive waste. In addition, they can use ISA as a source of food and energy under conditions that are expected in and around intermediate level radwaste disposal sites.

"Nuclear waste will remain buried deep underground for many thousands of years so there is plenty of time for the bacteria to become adapted," said Jonathan Lloyd, one of the researchers, in a news release. "Our next step will be to see what impact they have on radioactive materials. We expect them to help keep radioactive materials fixed underground through their unusual dietary habits, and their ability to naturally degrade ISA."

The findings are published in The ISME Journal