• Energy Research

Abstract The International Atomic Energy Agency (IAEA) has organised programmes on the development, comparison and testing of environmental assessment models and approaches for estimating the radiation exposure of humans and wildlife since the 1980s. The latest of these programmes was called MODARIA (Modelling and Data for Radiological Impact Assessment) and was run in two phases from 2012 to 2015 (MODARIA I) and 2016 to 2019 (MODARIA II). Both phases of the MODARIA programme had the overall objective to improve capabilities in the field of environmental transfer of radionuclides and public and non-human biota exposures assessment, by means of acquisition of improved data for model testing and comparison, reaching consensus on modelling philosophies, approaches and parameter values and building an international forum for the exchange of information. This paper provides an overview of the work undertaken during both phases of the MODARIA programme and its outputs. The overall aims and objectives of a new programme to follow on from MODARIA are described.

Abstract In response to changing international recommendations and national requirements, a number of assessment approaches, and associated tools and models, have been developed over the last circa 20 years to assess radiological risk to wildlife. In this paper, we summarise international intercomparison exercises and scenario applications of available radiological assessment models for wildlife to aid future model users and those such as regulators who interpret assessments. Through our studies, we have assessed the fitness for purpose of various models and tools, identified the major sources of uncertainty and made recommendations on how the models and tools can best be applied to suit the purposes of an assessment. We conclude that the commonly used tiered or graded assessment tools are generally fit for purpose for conducting screening-level assessments of radiological impacts to wildlife. Radiological protection of the environment (or wildlife) is still a relatively new development within the overall system of radiation protection and environmental assessment approaches are continuing to develop. Given that some new/developing approaches differ considerably from the more established models/tools and there is an increasing international interest in developing approaches that support the effective regulation of multiple stressors (including radiation), we recommend the continuation of coordinated international programmes for model development, intercomparison and scenario testing.