Thousands of tonnes of radioactive material which were dumped in the Irish Sea between 1950 and 1976 pose an extremely low risk to human health and marine life, a Department of the Marine task force has concluded.
The Minister for the Marine and Natural Resources, Dr Woods, said the report allayed genuine public anxiety about past radioactive dumping and was also a critical up-to-date assessment of its effects on public health and the marine environment.
The findings have proved controversial, with strong criticism from the Labour Party and the Greens.
The task force of scientists and marine experts was established in 1997 by Dr Woods, following an admission by the British government that radioactive material had been dumped at six locations in the Irish Sea.
The Green Party TD Mr Trevor Sargent said the report was more of a political face-saving exercise than a scientific report. "This matter cannot be put to rest until a full study of the seabed is carried out, rather than relying on water quality alone," he said.
The Green MEP Ms Patricia McKenna said there was no safe level of radiation and any radioactive discharge constituted a risk, no matter how small. The report's assertion that the dumping did not constitute a health hazard was simply irresponsible on the part of a national government supposed to safeguard the health and well-being of people.
Labour's marine spokesman, Mr Michael Bell, said the finding of no health risk would have to be treated with caution. Repeated independent surveys had shown alarming levels of radioactivity in the Irish Sea. "Only two years ago the Radiological Protection Institute found that some radioactive levels along the east coast were 30 times higher than four years previously," he said.
The report does, however, acknowledge that the possibility of this material resurfacing and being washed ashore could not be discounted.
Archive documentation show ed that material was dumped at sites at the Beaufort Dyke, the Holyhead Deep, Liverpool Bay, Morecambe Bay and in the Firth of Clyde off Garroch Head and the Isle of Arran. The radioactive material ranged from contaminated material from Glasgow and Edinburgh Universities, to industrial waste and material dumped by the Ministry of Defence.
On the basis of documentation provided by the British government the task force, assisted by the Radiological Protection Institute and the Department of Experimental Physics at UCD, conducted an assessment of the potential radiological consequences of the dumped material.
It concluded that the dumped material did not pose a health hazard. "The task force is of the view that members of the public have no reason, arising from the likely effects of this dumping, to be concerned about eating fish caught in the Irish Sea or the safety of swimming or participating in other water sports and recreational activities in the Irish Sea, along the Irish coast," the report said.
The findings were almost identical to the results of an assessment by the UK National Radiological Protection Board, published in 1997.
The brief of the task force did not extend to explosives and chemical weapons which were also dumped off the Donegal and Cork coasts. However, it noted that the Beaufort Dyke was a British and Irish munitions dump and acknowledged concerns that radioactive material could become dislodged, just as phosphorous devices dumped in the dyke had washed up on Scottish and Irish coastlines in 1995 and 1998.
The possibility of radioactive material becoming dislodged and resurfacing only existed in relation to material which was packaged and dumped in containers. But the chance of this occurring was very unlikely, given the location and depth at which this material was buried and that most items were dumped in steel containers encased in concrete, and the small number of items involved.
"However, although it appears highly unlikely, the possibility of return of the dumped material cannot be completely discounted," the report said.
The task force did not believe it was necessary or practical to attempt to retrieve the dumped material. Deliberate movement was likely to present a greater hazard than the very low risk that it might resurface.
The report recommended caution in carrying out works near any of the dump sites that may disturb the seabed, and advocated a careful assessment of any potential risks before such works are undertaken. The on-going marine radioactivity monitoring programme undertaken by the RPII was considered adequate and no additional monitoring was needed. But the report recommended that monitoring be maintained at current levels.
As part of its investigation the task force also interviewed a former seaman, Mr Walter Regan, who told The Irish Times in 1998 that from the late 1950s and early 1960s he dumped barrels of toxic and possibly radioactive waste into the sea, 60 miles south of Holyhead, when working for the Limerick Steamship Company. The report noted that, given the bonus payments to sailors, the cargoes might have been toxic, but the task force could not ascertain if they were radioactive.