A U.S. government researcher is studying ways to clea nse the body of nuclear fallout, using a chemical from crab and prawn shells.

As concerns over nuclear proliferation grow, so do worries that an attacker could set off a suitcase-sized bomb in a major city.

That would spread radioactive material over a wide area, exposing victims to various radioactive elements. Some of these can find their way into the body, where they keep producing radiation for years and often cause cancer.

There are no effective methods known to purge the body of this material, scientists say, although they have made some headway on treatments that temper its effects.

Tatiana Levitskaia of the Pacific Northwest National Laboratory in Richland, Wash., is researching a new approach. It’s based on a widely available material, chitosan, found in the shells.


A porcelain crab, Petrolisthes cinctipes. (Credit: Jonathon Stillman)

The substance, which is nontoxic, is a chelator, or compound that attaches itself to metallic atoms. Coincidentally, the word “chelator” itself has crabby origins; it’s derived from the Greek chele, or claw, because the chemical attachment mechanism is reminiscent of a lobster- or crab-like grasping action.

Chitosan can also be chemically modified to enhance its ability to clasp radioactive atoms, Levitskaia said. Many of the radioactive elements in nuclear fallout are metals, including plutonium, uranium, strontium and cobalt.

Chitosan is also easily expelled from the body, and scientists speculate that after linking to the radioactive substances it could take them with it. That would prevent their buildup in the bones, liver, kidneys and other organs.

For now, Levitskaia is investigating the effectiveness of chitosan and similar substances in removing cobalt from laboratory rats. She reported on her research at the national meeting of the American Chemical Society in mid-September, saying results are expected this fall.


- Courtesy Pacific Northwest National Laboratory
and World Science staff

ABOUT THE AUTHOR

Science writer Jack Lucentini is founder and editor of the World Science science news webzine. He has worked as a staff writer at three daily newspapers, and as a freelance science writer for a range of publications including The Washington Post, Discover magazine and The Scientist magazine. He earned his bachelor's degree at Oberlin College in Oberlin, Ohio in 1993.