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Radiological Monitoring
The Radiological
Protection Institute of Ireland (RPII) monitors radioactivity
in the Irish marine environment. This involves the routine sampling
and testing for radioactivity of fish, shellfish, seaweed, sediments
and seawater. The primary aim of the programme is to assess the
exposure to the Irish population resulting from marine radioactivity
and to estimate the consequent risks to health.
Particular attention is given to monitoring along Ireland's east
coast where discharges into the Irish Sea from the Sellafield
nuclear fuel reprocessing plant have resulted in enhanced levels
of artificial radioactivity.
The 2003
RPII Marine Monitoring Report (pdf) highlights discharged
radioactive waste from the Sellafield reprocessing plant as the
main source of artificial radioactivity in the Irish Sea. The
report details the results of the RPII's monitoring of radioactivity
in the Irish marine environment during 2000 and 2001.
The consumption of fish and shellfish is the
main way the Irish public are exposed to radiation as a result
of discharges from Sellafield. The doses due to eating fish and
shellfish, at 1.18 microsieverts (µSv) in 2000 and 1.20µSv
in 2001, appear to have reached a plateau in recent years. Commenting
on the report, the Institute's principal scientific officer, Dr
Tony Colgan stated that "these doses are very small and represent
less than 1% of the annual average radiation dose of approximately
3,620µSv received by members of the Irish public from all
sources of radiation. Consequently, they do not constitute a significant
health risk". He emphasised that "it continues to be
safe to eat seafood from the Irish Sea and to use the marine environment
for both leisure-based and commercial purposes".
RPII 2003
- Caesium-137 is the artificial radionuclide of greatest radiological
significance, accounting for approximately 60-70% of the total
radiation dose.
- The activity concentration of caesium-137 has remained relatively
stable since the mid-1990s but at a lower level than that observed
during the previous two decades. The highest activity concentrations
observed are on the north-east coastline.
- The other principal contributors to dose are technetium-99,
americium-241 and plutonium.
- Increased discharges of technetium-99 from Sellafield since
1994 have resulted in corresponding increases in the contribution
of this radionuclide to the doses to seafood consumers during
the period 1994 to 2001.
- Technetium-99 currently contributes up to 30% of the radiation
dose to typical consumers of fish and shellfish.
- Due mainly to the water circulation patterns in the Irish
Sea, the highest levels of contamination are usually found in
fish and shellfish samples collected from commercial landings
at the ports of Carlingford, Clogherhead and Howth.
Dr Colgan commented that "further reductions in these doses
are being pursued through the implementation of the OSPAR
Strategy with regard to Radioactive Substances. All Contracting
Parties to the OSPAR Convention for the Protection of the Marine
Environment of the North-east Atlantic have committed themselves
to progressive and substantial reductions in radioactive discharges
from their facilities (Sintra Declaration). Ireland is actively
engaged through the OSPAR Commission in ensuring that the discharge
strategies adopted by all parties to OSPAR (particularly France
and the UK who engage in the reprocessing of spent fuel) will
effectively meet the commitments set out in the Sintra Declaration
and reduce radioactive discharges to the marine environment."
The RPII continues to monitor the radiation levels in the Irish
Sea and to evaluate their impact on the Irish population and the
Irish marine environment. "In the Institute's view the highest
possible standards of safety and waste management should apply
to nuclear facilities, including the implementation of best available
techniques for the further reduction of discharges, with the goal
of minimising the environmental impact of discharges."
For more data see the RPII 2004
Marine Monitoring Results.
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