July 2003
Radioactive pollution in Solway '100 times higher than expected'
SUNDAY HERALD, 29 June 2003
By Michael RussellOriginal address: http://www.sundayherald.com/34913
[Posted 03/07/2003]
THE pollution of the Solway Firth by plutonium from the Sellafield nuclear complex is 100 times higher than previously thought -- and it could be moving northwards.
A new study, to be published by University College Dublin, will reveal levels of plutonium in the sediment under the sea far in excess of those highlighted by the government's green watchdog, the Scottish Environment Protection Agency (Sepa).
The researchers also discovered that, instead of staying trapped in the sediment, the plutonium was breaking loose and being carried north by currents. 'What we found was in keeping with a high level of remobilisation,' the study's main author, Julie Lucey, told the Sunday Herald.
Plutonium is one of the most toxic metals known, and even the tiniest amounts inside the body can increase the risk of cancer. Lucey said that, along with another toxic radioactive isotope, americium-241, it can be kicked up by storms, trawlers and even minute changes in the acidity of seawater.
This challenges the official view, long held by Sellafield's state-owned operators, British Nuclear Fuels, that heavy particles of plutonium sink to the bottom of the Irish Sea and are not disturbed. It means that the quarter of a tonne of plutonium dumped in the sea by Sellafield over the past 50 years will carry on contaminating the Scottish coast for many years to come.
The study was commissioned by the Scottish and Northern Ireland Forum for Environmental Research, of which Sepa and the Scottish Executive are members. It was supervised by former Nato consultant, Professor Peter Mitchell, and is due to be published within weeks.
Lucey and her team collected samples of sediment on a research cruise around the firths of Solway and Esk last summer. When analysed, they turned out to be contaminated by up to 15,000 becquerels of radioactivity per kilogram from plutonium and americium-241. Much lower levels of plutonium were recorded by Sepa in 2001 as part of the annual Radioactivity in Food and the Environment report. Samples taken by Sepa showed levels of 100-150 becquerel per kilogram in the Solway Firth.
But according to Sepa, this could be explained by the fact that the University College researchers had taken samples from deeper in the seabed. They went down 80cm, whereas samples for Sepa were usually taken from its surface. 'They went looking for high levels as a reference point,' said SEPA spokesman, Stewart Argo. 'Obviously, Sepa takes research of this sort very seriously, and, therefore, will need to consider its findings properly along with other factors that influence the monitoring programme.'
There was no significant risk to human health from the contamination, he argued. 'Our extensive national monitoring programme shows that there is no member of the Scottish public is exposed to unacceptable levels of man-made radiation through food or the environment.'
But the nuclear engineering consultant, John Large, who was in charge of hazard assessment during the recovery of Russia's Kursk nuclear submarine, said the study's findings were 'staggering'. He dismissed Sepa's assertion that radiation levels are higher deeper in the sediment.
'Sampling from the surface is dodgy because there are always day-to-day changes due to tidal currents,' he said. 'This study suggests that plutonium is much more mobile that hitherto thought. It is an enormous finding and would suggest that the previous assessment carried out by the Department for the Environment, Food and Rural Affairs is totally wrong.' Large also urged Sepa to extend its monitoring programme to more northerly waters to determine how far the pollution had spread. Lucey, from University College, said it was 'very likely' that similar findings would emerge if samples were taken in the Minch, between the Isle of Lewis and the mainland.
The Sunday Herald understands that a study of radioactive pollution in the Minch was conducted in 1999 by a team from the Dunstaffnage Marine Laboratory near Oban, but it has not yet been published. One of the scientists involved in the study, Dr Kenny Black, said the survey was in 'bits and pieces' and only required a month to collate and interpret the results. The University College study is entitled 'Solid speciation and remobilisation of caesium, americium and plutonium in the northern Irish Sea and south west coast of Scotland'.
Levels of caesium, and radioactive technetium-99, were lower than expected. But technetium-99, a byproduct of reprocessing spent nuclear fuel at Sellafield, is known to reach its highest levels in bladderwrack seaweed and lobsters, neither of which were sampled.
Last week, technetium-99 was also discovered at low levels in farmed Scottish salmon on sale in super markets.
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