The dose to Irish seafood consumers from Technetium-99

In this study, the effects of 99 Tc discharges from Sellafield to the Irish Sea on activity concentrations in fish and shellfish landed at ports on the north-east coast of Ireland and the resultant committed effective doses to typical and heavy consumers of seafood since 1990 are presented. Technetium-99 activity concentrations in fish and shellfish from the Irish Sea increased in the mid-1990s in line with increased discharges from Sellafield. In 2003, 99 Tc discharges were reduced and have now returned to the levels of the early 1990s. Although there has been a reduction in 99 Tc activity concentrations in fish and shellfish landed at ports on the north-east coast of Ireland, the dose to Irish seafood consumers has not returned to the baseline levels of the early 1990s, being greater by a factor of two. In 2006, 99 Tc accounted for approximately 15% of the total dose (0.16 and 0.75 µSv for typical and heavy consumers, respectively) to Irish seafood consumers from all artificial sources of radioactivity in the Irish Sea.