TOKYO, March 29 (Reuters) - The amount of plutonium detected at the quake-stricken plant in Japan is similar to that which would occur at a location far from an atmospheric nuclear test but is not harmful to people, the Nuclear and Industrial Safety Agency said on Tuesday.
In the latest blow to hopes that authorities were gradually getting the Fukushima Daiichi plant under control, plant operator Tokyo Electric Power Co said plutonium had been found at low-risk levels in soil samples at the facility.
“It (the amount of plutonium discovered) was the same level as normally found in the atmosphere as radioactive fallout after an atmospheric nuclear test, but a test done far away that would not directly affect someone,” Hidehiko Nishiyama, deputy director-general of the Nuclear and Industrial Safety Agency, said at a news conference.
The detection of plutonium at the site was further evidence that fuel rods in at least one of the six reactors may have melted down considerably before they were cooled, and that there is damage to the structures containing the nuclear core.
Only trace amounts of the toxic substance have been detected. The level of up to 0.54 becquerals per kg of soil is not considered harmful.
Plutonium-239, used most in reactors, has a half-life of 24,200 years. It is not readily absorbed by the body but what is absorbed, stays put, irradiates surrounding tissue and is carcinogenic. (Reporting by Terril Jones; Editing by John Chalmers and Joseph Radford)