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Abstract: Estimates of absorbed dose rates to wildlife from exposure to natural background radionuclides are required to put estimates of dose rates arising from regulated releases of radioactivity and proposed benchmarks into context. Recent review papers have estimated dose rates to wildlife from 40K, and 238U and 232Th series radionuclides. However, only one study previous has considered the potential dose rates to burrowing animals from inhaled 222Rn and its daughter products. In this paper we describe a study conducted at seven sites in northwest England. Passive track etch detectors were used to measure the 222Rn concentrations in artificial burrows over a period of approximately one year. Results suggest that absorbed dose rates to burrowing mammals as a consequence of exposure to 222Rn are likely to be at least an order of magnitude higher than those suggested in previous evaluations of natural background exposure rates which had omitted this radionuclide and exposure pathway. Dose rates in some areas of Great Britain will be considerably in excess of incremental no-effects benchmark dose rates suggested for use as screening levels. Such advised benchmark dose rates need to be better put into context with background dose rates, including exposure to 222Rn, to ensure credibility; although the context will be determined by the purpose of the benchmark and the assessment level. [Copyright &y& Elsevier]

A method is presented to calculate radiation dose rates arising from radon, thoron and their progeny to non-human biota in the terrestrial environment. The method improves on existing methodologies for the assessment of radon to biota by using a generalised allometric approach to model respiration, calculating dose coefficients for the ICRP reference animals and plants, and extending the approach to cover thoron in addition to radon-derived isotopes. The method is applicable to a range of environmental situations involving these radionuclides in wildlife, with an envisaged application being to study the impact of human activities, which bring NORM radionuclides to the biosphere. Consequently, there is a need to determine whether there is an impact on non-human biota from exposure to anthropogenically enhanced radionuclides., (Copyright © 2017 Elsevier B.V. All rights reserved.)

An international study under the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was performed to assess radiological impact of the nuclear accident at the Fukushima-Daiichi Nuclear Power Station (FDNPS) on the marine environment. This work constitutes the first international assessment of this type, drawing upon methodologies that incorporate the most up-to-date radioecological models and knowledge. To quantify the radiological impact on marine wildlife, a suite of state-of-the-art approaches to assess exposures to Fukushima derived radionuclides of marine biota, including predictive dynamic transfer modelling, was applied to a comprehensive dataset consisting of over 500 sediment, 6000 seawater and 5000 biota data points representative of the geographically relevant area during the first year after the accident. The dataset covers the period from May 2011 to August 2012. The method used to evaluate the ecological impact consists of comparing dose (rates) to which living species of interest are exposed during a defined period to critical effects values arising from the literature. The assessed doses follow a highly variable pattern and generally do not seem to indicate the potential for effects. A possible exception of a transient nature is the relatively contaminated area in the vicinity of the discharge point, where effects on sensitive endpoints in individual plants and animals might have occurred in the weeks directly following the accident. However, impacts on population integrity would have been unlikely due to the short duration and the limited space area of the initially high exposures. Our understanding of the biological impact of radiation on chronically exposed plants and animals continues to evolve, and still needs to be improved through future studies in the FDNPS marine environment., (Copyright © 2014 Elsevier B.V. All rights reserved.)