Fungus Could Be a Fix for Uranium Pollution

Enlarge Image Picture of fungus

Yum-yum!
It would sicken or kill other organisms, but this mycorrhizal fungus consumes depleted uranium and leaves it in a less mobile form.

Credit: Marina Fomina et al. (Current Biology 18)

Uranium pollution from high-tech armor and munitions is one of the dangerous legacies of the wars in the Balkans and Iraq. But a naturally occurring fungus might help combat the spread of that pollution into local ecosystems. The fungus transforms the uranium into a stable form that shouldn't work its way into the food chain, a new study shows. The findings potentially could help engineers isolate the toxic metal until better ways of cleaning up all but the most heavily contaminated sites can be developed.

Modern warfare has introduced a new and insidious type of pollutant to battlegrounds in the Middle East and Europe: depleted uranium. The compound consists of the nonexplosive uranium-238 that remains after the fissile uranium-235 has been extracted for making nuclear explosives and other purposes, plus a touch of titanium. Depleted uranium's high density makes it extremely useful for armor and munitions. But when shell collides with armor, fine particles scatter, so the military use of depleted uranium has left soil and water tables in battlegrounds polluted. Although less radioactive than natural uranium, the depleted form is nonetheless toxic and as hazardous as lead or mercury.

Researchers at the University of Dundee in the United Kingdom examined whether certain natural fungi could help clean up uranium from sites in the Balkans and Iraq. They knew from past studies that some types of fungi can ingest toxic substances without apparent harm. So in laboratory experiments, they fed depleted uranium to so-called mycorrhizal fungi, which usually live in the roots of plants, taking carbon from the plants and furnishing nutrients in return. Within a few months, the team reports tomorrow in Current Biology, the mycorrhizal fungi had surrounded and chemically transformed the depleted uranium to a stable phosphate compound. Because this compound isn't a nutrient, it doesn't work its way into the food chain.

Even better, this transformational ability of fungi "would work for pollution with any--depleted or not--metallic uranium and its corrosion products," says environmental microbiologist and lead author Marina Fomina. "Our findings could also be applied to cleaning up contaminated liquid wastes, metal leaching, and recycling and recovery," she says.

Soil ecologist John Dighton of Rutgers University in New Brunswick, New Jersey, calls the findings "great work" and an important step forward in identifying how fungi can slow the buildup of uranium in the environment. Understanding the role of fungi in radioactive and heavy-metal interactions in the soil is "important from many perspectives," he adds, particularly their impact on human health and the environment.

But when shell collides with armor, fine particles scatter, so the military use of depleted uranium has left soil and water tables in battlegrounds polluted. Although less radioactive than natural uranium, the depleted form is nonetheless toxic and as hazardous as lead or mercury.

It tends to be soluable when it is in its oxidized state. Once it gets into an anoxic part of an aquifer, it precipitates out of solution.

"the depleted form is nonetheless toxic and as hazardous as lead or mercury."

Nonsense. study after study shows that UNLIKE lead and mercury, DU does NOT accumulate in the brain, liver and kidneys. It's a much safer heavy metal.

Safe as dirt, however safe that is.

"So in laboratory experiments, they fed depleted uranium to so-called mycorrhizal fungi, which usually live in the roots of plants, taking carbon from the plants and furnishing nutrients in return. Within a few months, the team reports tomorrow in Current Biology, the mycorrhizal fungi had surrounded and chemically transformed the depleted uranium to a stable phosphate compound.

Key words there. We need do nothing at all, it's already present and working to neutralize all this "evil" DU, evil only because it has the word "uranium" in it, and we happen to make and use it to protect our troops from terrorist RPG attacks.

Who would have thought that the mycorrhizal fungi would turn out to be our friends? Thank you Marina Fomina et al. for letting us know.

6 posted on 05/07/2008 7:53:38 AM PDT by Dad yer funny (FoxNews is morphing , and not for the better ,... internal struggle? Its hard to watch)

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