TOKYO, June 7 (Xinhua) -- A worker has been found to have been exposed to as much as 22,000 becquerels of radioactivity following an accident at a research facility in Ibaraki Prefecture, northeast of Tokyo, local media said Wednesday.
According to officials from the Japan Atomic Energy Agency, up to 22,000 becquerels of plutonium 239 were found from the lung of a male worker and up to 14,000 becquerels of radioactive materials from the lung of another worker.
The men were conducting an inspection of fuel storage containers when a bag containing a powdered radioactive substance tore open and contaminated the men's gloves and protective clothing on Tuesday at the Japan Atomic Energy Agency's Oarai Research and Development Center.
Five workers at the facility were reportedly exposed to contaminants as a result of the accident, the facility said.
The worker who inhaled at least 22,000 becquerels of plutonium has had his condition described as "grave" by a member of Japan's nuclear watchdog, the Nuclear Regulation Authority. The man is in his 50s.
The workers have yet to complain of health issues, but an official at the facility said that future health-related problems were a high possibility and those most affected were likely suffering from internal exposure to radiation.
While the workers were wearing protective clothing including gloves and masks, it is believed that the highly toxic material could have been inhaled through holes in the masks and through gaps between the masks and the workers' faces.
Along with the others who were contaminated, the male worker who inhaled 22,000 becquerels of plutonium 239 was transported to the National Institute of Radiological Sciences in Chiba Prefecture near Tokyo for further investigations.
They were all reportedly given medicine to help their bodies discharge the radioactive materials.
The Japan Atomic Energy Agency had initially misreported the severity of the accident by saying that at the time just 24 becquerels had been found in the nasal passages of three of the workers.
When checked by a different machine, the science ministry confirmed that the maximum level of 22,000 becquerels had been detected in one of the workers.
According to Japan's public broadcaster NHK, Executive Officer of the National Institutes for Quantum and Radiological Science and Technology Makoto Akashi said that he has never heard of 22,000 becquerels being detected in a human body in Japan.
He said the figure is high and the impact on the worker's health will be dependent on the exact type of nuclide that was inhaled in the accident.
