One of the Irish authors of a survey on plutonium in teenagers' teeth has said it shows that plutonium from the Sellafield nuclear reprocessing plant was not detected in Irish people.
Dr Peter Mitchell, director of the radiation physics research team at UCD, said the survey, carried out on 3,350 adolescents' teeth in Britain and Ireland, showed that the extremely low amounts of plutonium in Irish people's teeth, and therefore bones, came from fall-out caused by nuclear weapons testing in the atmosphere.
He said there was a very small statistical increase in plutonium in samples taken closer to the Sellafield plant. However, samples taken in Antrim, Armagh, Down and Wexford showed the same extremely low plutonium levels as places far away from the Cumbrian plant.
The survey was conducted jointly by the departments of physics at UCD and Bristol University and the biomedical research department at AEA Technology in Harwell. The research on plutonium was done entirely at UCD.
This week's New Scientist quotes Prof Nicholas Priest, another of the survey's authors, as saying that most of the plutonium found in the teenagers' teeth "almost certainly" came from Sellafield. However, Dr Mitchell said he and Dr Priest agreed that what was being referred to here was "the minute amounts of excess plutonium in Cumbria which most likely come from the British Nuclear Fuels plant".
Dr Mitchell said the latest research arose out of a recommendation in the 1984 Black report, which had failed to confirm a linkage between leukaemia in children and radioactive waste discharges from Sellafield. However, it suggested further research based on measuring radiation received directly by the general public in Cumbria and further afield.
In the late 1980s another scientist, Dr Don Popplewell, tested autopsy samples and found "strong circumstantial evidence" that radioactive discharges from Sellafield - albeit at an extremely low level - had found their way into local people's bodies.
Dr Mitchell said the most important conclusion of the present study was that "we should be consoled that the human population of Britain and Ireland has only minute traces of plutonium in their bones, traces which are of no radiological significance whatsoever".
Most of the infinitesimal amounts of plutonium "arise from nuclear weapons testing in the late 1950s and early 1960s, and has very little to do with Sellafield", he said.
"Nuclear weapons fall-out plutonium dominates everywhere, but as you get closer to Sellafield there is statistical evidence of a very small increase on top of the weapons fall-out."
All records of radioactive dumping in the Irish Sea should be disclosed as a matter of urgency following the news that information has been found on two further instances of dumping in archive records, Mr John Gormley TD (Green) has said.
Mr Gormley said the first objective of the task force set up by the Minister for the Marine, Dr Woods, should be to insist that the British government examine all archival records so that the full extent of the potential danger to the Irish Sea is known. He accused the British government of drip-feeding information and said giving people little bits of information at different times could lead to them losing trace of the full extent of damage.