Radiocarbon in seawater at radioactive waste dumping sites in the Northeast Atlantic and Northwest Pacific.

Abstract

Radiocarbon has been an important constituent of radioactive wastes dumped in the open ocean and marginal seas as well as wastes released from nuclear reprocessing plants. Therefore, in some regions these sources could have a greater impact on (super 14) C concentration in seawater than global fallout. The high analytical sensitivity of (super 14) C measurement by accelerator mass spectrometry (AMS) allows even tracer amounts of (super 14) C to be found in seawater at radioactive waste dumping sites and their comparison with the global distribution of this radionuclide. Data on measurements of (super 14) C in samples taken at former dumping sites in the northeast Atlantic and northwest Pacific Oceans and in the open ocean are discussed and compared with other anthropogenic radionuclides, namely (super 3) H. Small increases in (super 14) C concentrations observed in some bottom and surface seawater samples collected at the Northwest Pacific Ocean dumping sites require further (super 14) C analyses before final conclusions can be made on possible leakages from dumped radioactive wastes.