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OSPAR Radioactive Substances Strategy
The objective of the OSPAR
Commission for the Protection of the Marine Environment of
the North-East Atlantic with regard to radioactive substances,
including waste, "is to prevent pollution of the maritime
area from ionising radiation through progressive and substantial
reductions of discharges, emissions and losses of radioactive
substances, with the ultimate aim of concentrations in the environment
near background values for naturally occurring radioactive substances
and close to zero for artificial radioactive substances."
As its timeframe, the Radioactive
Substances Strategy further declares that by the year 2020
the Commission will ensure that discharges, emissions and losses
of radioactive substances are reduced to levels where the additional
concentrations in the marine environment above historic levels,
resulting from such discharges, emissions and losses, are close
to zero.
Since the 1950s, inputs of artificial radionuclides to the marine
environment west of Great Britain and around Ireland (OSPAR Region
III Celtic Seas) have been dominated by discharges from the British
Nuclear Fuels Plc nuclear reprocessing facilities at Sellafield
(formerly Windscale) on the Cumbrian coast of Northwest England.
According to the OSPAR Commission (2000), the magnitude of these
authorised releases "has tended to mask contributions of
radionuclides from other sources such as the 1986 Chernobyl accident,
the effects of which are largely terrestrial, and residues from
atmospheric weapons testing."
"In addition to Sellafield, a number of establishments on
the west coast of Great Britain are also authorised to release
small amounts of radioactivity. The activities concerned include
power generation, nuclear fuel production, manufacturing of medical
supplies and military/naval operations. Their discharges and the
adjacent environments are subject to regular monitoring. In all
cases the resulting public radiation exposures are very low and
difficult to distinguish from radiation due to Sellafield and
nuclear fallout." (OSPAR 2000)
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| Location of BNFL Sellafield relative to
OSPAR Region III Celtic Seas |
The OSPAR Commission's overall assessment refers to "recent
increases in the discharge of certain radionuclides, particularly
technetium-99" from Sellafield. OSPAR (2000) states:
"However, technetium is of low radiological significance
and there have been substantial net reductions in the levels of
many other more harmful radionuclides over the last decade …
Recent OSPAR commitments indicate this process (including reductions
in technetium) is likely to continue and that radioactivity levels
will continue to decline. In terms of exposure to the public,
the incremental risks to health due to present discharges from
Sellafield are extremely small.
For example, in Ireland a heavy consumer of fish and shellfish
from the Irish Sea in 1997 would have received an estimated dose
of 1.4µSv compared to the current dose limit which is set
at 1,000µSv. This would amount to an addition of 0.05% to
the average dose of 3,000µSv received from all other sources
of radiation. In the UK the highest reported dose was received
by consumers on the Cumbrian coast in 1981, amounting to 3,450µSv
or 69% of the then recommended dose limit of 5,000µSv (using
an enhanced gut transfer factor for plutonium). Exposure levels
to marine species are also well below those known to cause adverse
effects."
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