The Health Physics Society has put out an information sheet on polonium-210, the radioactive material that was found in the body of former Russian spy Alexander Litvinenko. The fact sheet explains in particular the effects of polonium-210 on the intestinal lining.
San Francisco Chronicle science writer Keay Davidson found out that it’s easy to buy “trace amounts” of the isotope for $69 on the Web site of a company that sells scientific equipment. (Radioactive isotopes are used in all sorts of research — for example for tagging specific snippets of DNA — and have of course many uses in medicine, for example in PET scans.) However, the company’s site says, “You would need about 15,000 of our Polonium-210 needle sources at a total cost of about $1 million — to have a toxic amount.”