Research and analysis

Seaweed: transfer of radioactivity to foodstuffs

This report (HPA-RPD-059) describes the transfer of radioactivity from seaweed to terrestrial foods and potential radiation exposure.


HPA-RPD-059: transfer of radioactivity from seaweed to terrestrial foods and potential radiation exposures to members of the public

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Radionuclides are discharged into the Irish Sea from the Sellafield nuclear fuel reprocessing plant in Cumbria and can become concentrated in seaweed. This seaweed can be used as a fertiliser and soil conditioner and in some instances is grazed by animals directly on the foreshore. This practice is known to have been prevalent in Scotland in the past and continues to a limited extent today. This provides a route for the transfer of radionuclides into terrestrial food chains.

This study aimed to identify the extent of seaweed use in Scotland at the time, the practices adopted, the extent to which food grown on seaweed treated land is consumed by individuals and to estimate potential radiation doses from ingestion of these foods. Samples of seaweed, soil, crops and animal products were analysed for a range of radionuclides.

The radiation doses estimated would not justify a major programme of continuous monitoring. However, data from current monitoring programmes could be used to identify any trends which might suggest a requirement for changes to the programme.

Published 1 November 2009