Level characteristics and dose assessment of organically bound tritium and carbon-14 in marine biota from the Taiwan Strait

Tritium (3H) and carbon-14 (14C) are radionuclides present in Fukushima nuclear contaminated water in Japan that are difficult to effectively remove, their potential risks to marine ecosystem safety have raised extensive concern. This study assessed the pollution levels of organically bound tritium (OBT) and 14C in seafoods from Taiwan Strait. The results showed that in the eatable part of marine biota, the specific activities of OBT and 14C ranged from 14C in marine biota of the Taiwan Strait were comparable to those in other nearshore areas in China, while the specific activities of 14C were much lower than those in marine biota around the Sellafield spent fuel reprocessing plant in the UK. Further dose assessment revealed that the average annual committed effective doses for Fujian residents due to the consumption of OBT and 14C in seafood were 8 × 10−4 μSv and 0.18 μSv, respectively, with a maximum combined dose of 0.45 μSv, which was far below the dose limit (1000 μSv) stipulated by the national standard (GB 18871－2002). The results of this study can provide key data references for evaluating the potential impact of Fukushima nuclear contaminated water on Fujian marine environments and for alleviating public anxiety.