The Global Scenario and Challenges of Radioactive Waste in the Marine Environment

The present special issue of Pure and Applied Chemistry (PAC) comprises a series of papers prepared by task group members of IUPAC project no. 2021-027-2-600 titled “The Global Scenario and Challenges of Radioactive Waste in the Marine Environment”. This project was proposed and subsequently led by project co-chairs Joon Ching Juan, from the Nanotechnology and Catalysis Research Centre (NANOCAT), University of Malaya, Malaysia and Silvina A. Di Pietro from the Lawrence Livermore National Laboratory (LLNL), Livermore, USA. It has been undertaken to provide an interdisciplinary approach to the provision of knowledge about the fate and transport of radioactive waste in the marine environment.

For decades, radionuclides have been released to the aquatic environment as the result of reactor accidents (e.g., at Chernobyl and Fukushima), fuel production facilities/fuel reprocessing plant discharges (e.g., La Hague in France and the Windscale/Sellafield complex in the UK.), aircraft accidents (e.g., loss B52 aircraft carrying nuclear weapons at Palomares, Spain and Thule, Greenland) and reactor disposals (e.g., Soviet ice breaker and submarine reactors in the Kara Sea). Such radionuclides become redistributed by ocean currents, may subsequently be trapped in sediments and widely accumulated by biota. They may also be returned to the land by sea-to-land transfer. While discharges to the sea have been used to map ocean currents, they also present a potential hazard to biota and human beings. For example, ruthenium-106, technetium-99 and caesium-137 have all been shown to have entered the human food chain. However, information on radionuclides in the ocean is dispersed. The IUPAC project aimed to bring together relevant information in a single referenced document. Its interdisciplinary approach included social science approaches.

The IUPAC project aims to provide state-of-the-art critical reviews of the current knowledge and understanding of radionuclides in the ocean, with special reference to those that are anthropogenic in origin. The results of specific tasks are presented, as papers in this special issue of Pure and Applied Chemistry:

1. Transport of radioactive materials from terrestrial to marine environments in Fukushima over the past decade.

2. A critical review of the quantification, analysis and detection of radionuclides in environment using Diffusive Gradients in Thin films (DGT): advances and perspectives.

3. Impact of fluvial discharge on ¹³⁷Cs in the ocean following the Fukushima Daiichi Nuclear Power Station accident.

4. Radionuclides in marine sediment.

5. Speciation and mobility of uranium isotopes in the Shu River: impacts for river to sea transfer.

6. Overview of marine radionuclide contamination from sampling to detection.

7. The transfer of irradiated uranium from the Irish Sea Coast to the terrestrial environment in Cumbria, UK.

8. Public knowledge, sentiments, and perceptions of low dose radiation (LDR) and power production, with special reference to reactor accidents.

These papers cover a wide range of topics concerned with novel radionuclide analytical methods, the environmental speciation of radionuclides in riverine and ocean waters and their association with widely mobile sediments. Reference is made to the impact of nuclear accidents, including those at Chernobyl and Fukushima, on receiving marine environments. Two papers review the impact of the 2011 Fukushima nuclear disaster that released a significant amount of radioactive contamination. It is estimated that 18,000 TBq of radioactive caesium-137 was discharged into the Pacific Ocean. These papers refer to processes that result in the redistribution of radionuclides between environmental compartments and inform environmental models. Papers describe air-to-sea, sea-to-land and land-to-sea transfers, including those resulting from fluvial discharges. It is recognized that the most significant radionuclide ocean contaminations result from the activities of the civilian nuclear industry and industrial accidents have impacted attitudes to the industry. It follows, a social science paper is included that reviews public attitudes to low dose radiation and the nuclear industry, which is important because the future of discharges to the marine environment is inevitably linked to the future of nuclear power – a future that is impacted by public opinion.