Highly toxic plutonium has been released in an accident within the Sellafield nuclear reprocessing plant in Cumbria.
A group of 72 workers was forced to evacuate a laboratory at midday yesterday where the leak of plutonium oxide occurred. One worker was found to have been contaminated externally by the release but this was cleaned away, according to a spokeswoman for BNFL which operates the plant.
The Minister of State at the Department of Enterprise and Employment with responsibility for nuclear safety, Mr Joe Jacob, said last night he would be pursuing his UK counterparts for more information about the incident "as a matter of urgency".
"Departmental officials and the Radiological Protection Institute of Ireland would be seeking immediate clarification regarding the latest incident at Sellafield," he said.
The leak, which set off automatic alarms, occurred at the "B33 MOX Demonstration Facility" according to a BNFL statement. This is a prototype part of the Sellafield plant which makes an advanced fuel mix combining uranium and plutonium recovered from reprocessing activities.
"During routine operations there was a minor escape of radioactivity that was contained within the building itself," according to the statement. Alarms were triggered and staff occupying the facility were evacuated.
There had been "no release" outside the laboratory or the plant, a BNFL spokeswoman said last night. Staff were last night back in the laboratory assessing the extent of the release.
There were filters and other safety equipment to prevent the powdered plutonium oxide from escaping, she said. The statement added that "grass samples had been taken in order to confirm that there was no release of activity from the building".
The RPII had already received an initial report on the incident according to its chief executive, Dr Tom O'Flaherty. "We will certainly be in contact [today] with the Nuclear Installations Inspectorate and BNFL," he said.
"This incident in itself does not have any consequences for Ireland, but every incident naturally increases concerns in this country about the possibility of a major accident which would affect us," he added.
One Sellafield worker was found to have been contaminated and was sent to the site surgery, according to the BNFL statement. "Initial testing of that individual has not shown any internal contamination and all external contamination has been removed. Other personnel were monitored prior to being allowed to go home and everyone was found to be clear," according to BNFL.
Plutonium is particularly dangerous as it stays radioactive for many centuries. While it is relatively simple to afford external protection against it, the great risk is that the plutonium would enter the body, for example by being breathed in. Once in the lung the plutonium would cause significant and persistent damage to tissues, leading in turn to cancers.
BNFL would have been required to report the incident to the relevant UK regulatory authorities. The company confirmed that these had in fact been briefed.