R01055: Accumulation and re-mobilisation of technetium-99 (Tc-99) in eastern Irish Sea sediments
Friday 8 October 2004
This research project aims to confirm whether Tc-99 is accumulated in Irish Sea sediments.
Background
Technetium-99 is present in the liquid effluent discharged into the Irish Sea from the BNFL reprocessing plant at Sellafield. Monitoring results indicated that Tc-99 accumulates in Irish Sea sediments. This project aims to confirm this and assess the implications for seafood contamination.
Results and findings
Results from the sediment core data show that Tc-99 from Sellafield has penetrated below 30cm into the sediment. Derived transfer factors for coastal sediments were roughly an order of magnitude higher than those recommended by the International Atomic Energy Agency.
Results from laboratory experiments indicated that there was little or no uptake of Tc-99 from seawater onto some sediment. Removal of contaminated sediment to uncontaminated seawater showed that re-dissolution varied with different sediment types. For oxidising sediment this was rapid whereas for anoxic sediments Tc-99 remained bound.
The results have been used to assess the implications for seafood contamination and will be used to update the models used by the FSA to assess doses to consumers of seafoods.
Dissemination information
The final report is available from the FSA Library and Information centre.
To obtain a copy, please contact the Enquiry Desk, Dr Elsie Widdowson Library and Information Services, Food Standards Agency (tel: 020 7276 8181/8182 or email: library&info@foodstandards.gsi.gov.uk)
Contact: For any enquiries concerning this research project, please contact the relevant Programme contact or email science@foodstandards.gsi.gov.uk