Green Algae Could Help Clean Up Nuclear Waste

Fox News - Fair & BalancedAlgae Could Be Key to Cleaning Up Nuclear Accident Sites - FoxNews.com

Algae can secrete biofuels and pump out biologic drugs, and now researchers think it could help clean up radioactive accidents like the one unfolding at Japan's Fukushima nuclear facility.
A Northwestern University researcher has identified a certain kind of common algae, known as Closterium moniliferum, that has a unique penchant for sequestering strontium into crystals, a trick that could help remove the dangerous radioactive isotope strontium-90 from the environment.

Pond Alga Could Help Scientists Design Effective Method for Cleaning Up Nuclear Waste: McCormick School of Engineering at Northwestern

The crescent-shaped, single-celled organism studied by Joester and his colleagues naturally makes biominerals that include non-radioactive strontium, and it can differentiate strontium from calcium -- a rare feat. The researchers want to learn more about this selectivity because calcium is present in far greater abundance than strontium in nuclear waste, but calcium is harmless. By concentrating the radioactive strontium (Sr-90) in the form of solid crystals with very low solubility, the dangerous high-level waste could be isolated from the rest and dealt with separately.


Joester, Krejci, Finney and Vogt all are authors of the paper, titled “Selective Sequestration of Strontium in Desmid Green Algae by Biogenic Co-precipitation with Barite.”

What’s the Context: The danger of strontium-90 is that it is chemically similar to calcium, and so can be taken up into milk, bones, and other tissues. Nuclear waste and spills can contain significant amounts of strontium; C. moniliferum is especially helpful because it can precipitate strontium but leave calcium alone (calcium is different enough from barium that the bacteria doesn’t crystallize it).

Not So Fast: Scientists don’t yet know how well the algae can withstand radioactivity, which could potentially put a damper on this clean-up method. Now, the scientists would like to find ways of increasing sulphate levels in the environment, which may in turn increase the ability of the algae to crystallize strontium.