The radioactive material that killed a former Russian spy in Britain can be bought on the Internet for $69.

Polonium-210, which experts say is many times more deadly than cyanide, can be bought legally through United Nuclear Scientific Supplies, a mail-order company that sells through the Web. Chemical companies sell the Polonium-210 legally for industrial use such as removing static electricity from machinery. United Nuclear claims that the material is "currently the only legal Alpha source available without a license."

The type of Polonium-210 sold emits alpha radiation, which can't penetrate the skin but is deadly if swallowed, depending on the amount ingested. The Polonium available on United Nuclear's site can be purchased without a license because the level of radioactivity, 0.1 microcurie, doesn't pose a danger, a spokesman for the U.S. Nuclear Regulatory Commission says.

"At that level, it's exempt from licenses," NRC spokesman David McIntyre says. "At any exempt quantity, it's not considered a health hazard."

Such small amounts of Polonium could be used to calibrate devices used to detect radiation, McIntyre says. If used for that purpose, the material would remain in its sealed container and never actually handled.

United Nuclear is run by Bob Lazar, who some 20 years ago claimed to have worked on alien spaceships on a secret military base in Nevada, the San Francisco Chronicle reported. Lazar was unavailable for comment on Tuesday.

In April, United Nuclear was ordered by the Department of Justice to stop selling chemicals that it claimed could be used to make explosives, the Albuquerque Journal reported. At the time, Lazar said he was fighting the legal challenge.

On the site, United Nuclear says it will not sell anything illegal, including explosives or the materials to make explosives. "Because our products can be potentially hazardous in the wrong hands, we will occasionally terminate and refund orders if we feel you are a juvenile posing as an adult, inexperienced with the materials ordered, or using our products to make any sort of explosive device," the company says.

British authorities believe former KGB agent Alexander Litvinenko died of Polonium-210 poisoning and have opened a formal inquest. Litvinenko, who died last week in a British hospital, claimed he was poisoned on behalf of Russian President Vladimir Putin. Putin denies any involvement. United Nuclear hasn't been linked in any way to the Litvinenko case.