Transuranic nuclides in plaice (Pleuronectes platessa) from the North-Eastern Irish Sea

The concentrations of a number of -emitting nuclides, ²³⁸Pu, ^239/240Pu, ²⁴¹Am, ²⁴²Cm and ^243/244Cm have been determined in the organs of plaice, Pleuronectes platessa L., caught in the vicinity of a nuclear fuel reprocessing plant. Fish were taken for analysis every 3 months for a period of 2 years. During this period, the highest concentrations of plutonium and americium nuclides were found in the kidney and the lowest in muscle. In all of the organs analysed, the concentrations of americium were greater than those of plutonium: they were also greater than plutonium when related to the rates of discharge of these two elements and gave higher concentration factors over samples of filtered shore-line sea water taken from the area.