22,000 becquerels of plutonium-239 and 220 becquerels of americium-241 found in lungs of nuclear facility worker

 

‘No one has inhaled this much plutonium’: 5 staff exposed to radiation in Japan lab accident

Japanese authorities are unsure about the medical prognosis for five staffers who inhaled toxic plutonium after mishandling it at the Oarai Research and Development Center outside Tokyo.

“As far as I can remember, no one has inhaled plutonium at this level,” said Ishikawa Keiji, a security official at the Japan Atomic Energy Agency (JAEA) which oversees the lab, cited by the Jiji Press news agency.

The accident occurred at 11:15am on Tuesday in the analysis room of the facility dedicated to researching improved nuclear fuel for its fast reactors.

One of the five men opened a metallic cylinder where the fuel, a mixture of uranium and plutonium, is stored before and after experiments. In the process, the double plastic wrapping inside which the radioactive material is kept ripped, and the toxic substance burst into the air.

Shunichi Tanaka, chairman of the Nuclear Regulation Authority (NRA), which has frequently criticized the JAEA for the conditions at its facilities, said “workplace complacency” was possibly to blame.

The NRA said the workers had never experienced a similar plastic rip before, and as a result, did not feel the need to complete their research in a tightly sealed environment.

The researcher responsible for opening the box, described as a man in his 50s, had 22,000 becquerels of plutonium-239 detected in his lungs, and the other four between 2,200 and 14,000 becquerels.

Officials said the five staff have not yet complained of health problems with one assuring that “the amount is not enough to cause acute radiation damage,” according to the Japanese newspaper The Asahi Shimbun.

The longer-term predictions were less definitive, however.

“Detection of 22,000 becquerels is a situation that cannot be easily brushed aside. It is no small amount, although it may not be life-threatening,” said Nobuhiko Ban, an NRA radiological protection specialist, quoted by The Asahi Shimbun. 

The five have been injected with a substance that speeds up the discharge of radioactive materials and remain under observation at the National Institutes for Quantum and Radiological Science and Technology.

The NRA has previously said that JEAA was “unfit” to operate an accident-plagued prototype reactor at Monju and has also faced accusations of poor handling of radioactive materials at another site.

But a use for Japan’s large plutonium stockpile must be found, and there are currently plans for utilizing MOX fuel – a mixture of plutonium and uranium, such as that involved in the latest accident – to power conventional reactors instead of the low-enriched uranium that they were designed for.

https://www.rt.com/news/391283-japan-nuclear-accident-plutonium/

‘No one has inhaled this much plutonium’: 5 staff exposed to radiation in Japan lab accident

Japanese authorities are unsure about the medical prognosis for five staffers who inhaled toxic plutonium after mishandling it at the Oarai Research and Development Center outside Tokyo.

“As far as I can remember, no one has inhaled plutonium at this level,” said Ishikawa Keiji, a security official at the Japan Atomic Energy Agency (JAEA) which oversees the lab, cited by the Jiji Press news agency.

The accident occurred at 11:15am on Tuesday in the analysis room of the facility dedicated to researching improved nuclear fuel for its fast reactors.

One of the five men opened a metallic cylinder where the fuel, a mixture of uranium and plutonium, is stored before and after experiments. In the process, the double plastic wrapping inside which the radioactive material is kept ripped, and the toxic substance burst into the air.

Shunichi Tanaka, chairman of the Nuclear Regulation Authority (NRA), which has frequently criticized the JAEA for the conditions at its facilities, said “workplace complacency” was possibly to blame.

The NRA said the workers had never experienced a similar plastic rip before, and as a result, did not feel the need to complete their research in a tightly sealed environment.

The researcher responsible for opening the box, described as a man in his 50s, had 22,000 becquerels of plutonium-239 detected in his lungs, and the other four between 2,200 and 14,000 becquerels.

Officials said the five staff have not yet complained of health problems with one assuring that “the amount is not enough to cause acute radiation damage,” according to the Japanese newspaper The Asahi Shimbun.

The longer-term predictions were less definitive, however.

“Detection of 22,000 becquerels is a situation that cannot be easily brushed aside. It is no small amount, although it may not be life-threatening,” said Nobuhiko Ban, an NRA radiological protection specialist, quoted by The Asahi Shimbun. 

The five have been injected with a substance that speeds up the discharge of radioactive materials and remain under observation at the National Institutes for Quantum and Radiological Science and Technology.

The NRA has previously said that JEAA was “unfit” to operate an accident-plagued prototype reactor at Monju and has also faced accusations of poor handling of radioactive materials at another site.

But a use for Japan’s large plutonium stockpile must be found, and there are currently plans for utilizing MOX fuel – a mixture of plutonium and uranium, such as that involved in the latest accident – to power conventional reactors instead of the low-enriched uranium that they were designed for.

https://www.rt.com/news/391283-japan-nuclear-accident-plutonium/

High level of radiation found in lungs of nuclear facility worker

OARAI, Ibaraki — A worker at a research and development (R&D) center here has been found to have a high level of radioactive material — up to 22,000 becquerels — in his lungs following exposure to radiation, the center said on June 7.

The discovery came after five workers at the Oarai Research & Development Center, which belongs to the Japan Atomic Energy Agency, were exposed to radioactive materials on June 6.

Radioactive materials are difficult to expunge from the human body, and it is thought that the level of internal exposure in this case will be 1.2 sieverts in one year, and 12 sieverts over 50 years.

The five workers have been taken to the National Institutes of Radiological Sciences in Chiba Prefecture, where they are undergoing examinations.

At a Nuclear Regulation Authority (NRA) meeting on June 7, a committee member said the workers’ situation is “not mild.”

According to organizations such as the NRA, one of the five workers was found to have up to 22,000 becquerels of plutonium-239 and 220 becquerels of americium-241 in his lungs. Two other workers were discovered to have 12 becquerels and 130 becquerels of americium-241 in their lungs, respectively. All five workers were administered medicine designed to reduce the radiation dose of the internal exposure.

The five workers were all wearing protective clothing and face masks at the time of the radiation exposure, the R&D center said. It is currently being investigated whether or not there were any problems at the time the incident happened.

Plutonium and americium are both harmful to human bodies as they emit alpha rays.

http://mainichi.jp/english/articles/20170607/p2a/00m/0na/018000c

Four workers exposed to radioactive materials at Ibaraki nuclear facility

Four workers suffered internal radiation exposure due to inhalation of a large amount of plutonium during an inspection at a nuclear research facility in Ibaraki Prefecture on Tuesday, the operator of the facility said Wednesday.

In the wake of what appears to be an unprecedented internal radiation exposure accident, the state’s nuclear safety regulator and local labor authorities inspected the scene to see if there were any flaws in safety management.

The accident occurred at the fuel research building of the Japan Atomic Energy Agency’s Oarai Research & Development Center when a bag covering a container for nuclear fuel materials, including powder samples of plutonium and uranium, tore during inspection on Tuesday.

Up to 22,000 becquerels of plutonium 239 were detected in the lungs of a male worker in his 50s. Up to 14,000 becquerels of radioactive materials were found in the three other workers, officials of the Japan Atomic Energy Agency said.

The Nuclear Regulation Authority said the worker with the higher reading has been exposed to an extreme amount of radiation and the situation is considered grave.

While none of the workers have complained of health problems so far, an official with the facility’s operator said it “cannot rule out the possibility of future health effects.”

The agency assumes that the amount of radiation exposure of the male worker in his 50s translates to up to 12 sieverts over 50 years, well above the legal limit set for workers who deal with radiation.

For its part, the labor office said that it estimates the man with the highest exposure to radiation has exceeded the annual limit of radiation exposure, which is 50 millisieverts a year and 100 millisieverts in five years.

Plutonium is known to emit alpha rays over a long period, damaging surrounding organs and tissues. If it is deposited into the lungs, it could increase the risk of developing cancer

The five workers have been transported to the National Institute of Radiological Sciences and given medication to help discharge radioactive materials from their bodies.

“I saw such a (high) figure for the first time,” said Makoto Akashi, a senior official at the National Institutes for Quantum and Radiological Science and Technology, referring to the reading of 22,000 becquerels. The institute oversees the National Institute of Radiological Sciences.

“It is very clear from a scientific viewpoint that the internal exposure to radiation would increase the risk of cancer (for the workers),” Akashi said.

“I have never heard of such a large amount as a reading for internal exposure to radiation,” Shunichi Tanaka, who heads the NRA, told a separate news conference.

The workers wore masks but could have inhaled radioactive material from the small gaps between the masks and their faces.

Kunikazu Noguchi, an expert on radiological protection and associate professor at Nihon University, said it is hard to conclude the impact of the 22,000 becquerels, as the actual amount of radioactive substances he inhaled is still unknown.

“It is possible, however, that the worker could have been exposed to more radioactive materials than the legally allowable maximum limit,” Noguchi said. He said it is necessary to get to the bottom of the incident, especially whether workers followed guidelines, as it is hard to imagine a plastic bag containing nuclear substances could tear in such a facility as the Oarai center.

http://www.japantimes.co.jp/news/2017/06/07/national/five-workers-exposed-radioactive-materials-ibaraki-nuclear-facility/#.WTkK8zekLrc

Worker at Ibaraki facility has up to 22,000 becquerels of plutonium in lungs

TOKYO – Five workers have suffered internal radiation exposure, with one found with up to 22,000 becquerels of plutonium in his lungs, following an inspection accident at a nuclear research facility in Ibaraki Prefecture on Tuesday, the operator of the facility said Wednesday.

In one of the worst accidents involving internal radiation exposure in Japan, up to 5,600 to 14,000 becquerels of plutonium 239 have been detected from the other three workers, the Japan Atomic Energy Agency said.

The accident occurred at the fuel research building of the agency’s Oarai Research & Development Center when a bag covering a container for nuclear fuel materials, including powder samples of plutonium and uranium, tore during inspection.

A labor standards inspection office in Ibaraki conducted an inspection Tuesday and Wednesday at the building, while the Nuclear Regulation Authority, the nuclear safety watchdog, also dispatched an inspector to the scene to check whether there were any violations of safety regulations.

The agency estimates that the amount of radiation exposure of the man with the highest level translates to up to 12 sieverts over 50 years.

The labor office believes that the man in his 50s has exceeded the annual limit of radiation exposure of 0.1 sievert in five years set for those who handle radioactive materials.

Plutonium is known to emit alpha rays for a long period, damaging surrounding organs and tissues. If it is deposited into the lungs, it could increase the risk of developing cancer.

The Japan Atomic Energy Agency has said the operation by the workers was carried out as usual.

Nuclear Regulation Authority Chairman Shunichi Tanaka said of the incident at a press conference, “Perhaps (the workers) have become too accustomed to plutonium. I urge careful handling.”

“As (a level for) internal radiation exposure it’s an amount unheard of,” he said.

“We shouldn’t downplay the situation,” said NRA Commissioner Nobuhiko Ban, a specialist in radiological protection.

While none of the workers has complained of health problems so far, an official of the facility operator said it “cannot rule out the possibility of future health effects.”

The five workers have been transported to the National Institute of Radiological Sciences and given medication to facilitate the discharge of radioactive materials from their bodies.

Since radioactive materials were found on hands and faces of four of the five workers, they have been decontaminated, said an official of the National Institutes for Quantum and Radiological Science and Technology, an umbrella organization of the National Institute of Radiological Sciences.

The workers wore masks to cover their mouths and noses but could have inhaled the radioactive materials from the small gaps between the masks and their faces.

The Japan Atomic Energy Agency has previously come under criticism for lacking safety awareness, following revelations of a massive number of equipment inspection failures at its Monju prototype fast-breeder nuclear reactor in Fukui Prefecture.

The Japanese government decided to decommission Monju last year after it has barely operated over the past two decades despite its envisioned key role in the country’s nuclear fuel recycling policy.

https://japantoday.com/category/national/5-workers-suffer-radiation-exposure-one-with-up-to-22-000-becquerels-of-plutonium-in-his-lungs#.WTh8DhaVAOw.facebook

 

 

June 9, 2017 - Posted by dunrenard | Japan | Exposure, Ibaraki Prefecture, Oarai Research & Development, plutonium, radiation, Workers