Marine Chemistry 
Nordseezustand 2004 
27 
waters. These enhanced concentrations are attributable chiefly to the presence of re 
suspended material from highly polluted sediments of the Irish Sea and recent dis 
charges of the Sellafield nuclear reprocessing plant. Spatial distributions of 90 Sr activ 
ity contained a characteristic riverine signal, which concurrently peaked with Elbe 
River discharge rates in March. 
On average, the total effective dose per person and year in Germany is 4 mSv, half of 
which is attributable to medical treatments, especially x-ray diagnostics. Radioactive 
contamination of the North Sea may contribute to radiative exposure of the population 
but through the pathway consumption of fish and other seafood. An average consump 
tion of 14 kg per year would result in an effective dose of at most 0.2 pSv/a, which is 
far below the »trivial dose< of 10 pSv/a as defined in the German Radiation Protection 
Ordinance. As the enrichment of radionuclides in the food chain does not contribute 
significantly to the total exposure of humans, this is likely to apply to flora and fauna in 
the North Sea as well.