Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium

Abstract

This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters’ accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research conducted in a variety of laboratory and field settings has improved our knowledge of the effects of ionizing radiation on the environment. However, the results from such studies sometimes appear contradictory and there is disagreement about the implications for risk assessment. The Symposium discussions therefore focused on issues that might lead to different interpretations of the results, such as laboratory versus field approaches, organism versus population and ecosystemic inference strategies, dose estimation approaches and their significance under chronic exposure conditions. The participating scientists, from across the spectrum of disciplines and research areas, extending also beyond the traditional radioecology community, successfully developed a constructive spirit directed at understanding discrepancies. From the discussions, the group has derived seven consensus statements related to environmental protection against radiation, which are supplemented with some recommendations. Each of these statements is contextualized and discussed in view of contributing to the orientation and integration of future research, the results of which should yield better consensus on the ecological impact of radiation and consolidate suitable approaches for efficient radiological protection of the environment.

An Extended Dose–Response Model for Microbial Responses to Ionizing Radiation

“…This concept acknowledges that there may be some differences between the effects of IR on a range of organisms but excludes microbes. The Miami Consenus Symposium 2015 derived seven statements to address the ecological effects of radiation on populations and ecosystems and yet there has been scant focus on radiological protection for microorganisms (Bréchignac et al, 2016). This is important when the recent data outlined above suggests that the effects of IR on microbial populations is not the same as the effects on populations of other organisms.…”

Radiological risk assessment: an overview of the ERICA Integrated Approach and the ERICA Tool use

“…In order to calculate the dose-rate, activity concentration data are used in equations [5] and [6] given below. Through equations we derive the internal (D int ) and external (D ext ) absorbed dose rates in µGyh -1.…”

“…is radionuclide-specific dose conversion coefficient defined as the ratio between the average activity concentration of radionuclide i in the organism b and the dose rate to the organism b (in µGy h -1 per Bq kg -1 fresh weight). [6] where: v z is the occupancy factor (i.e. fraction of time that the organism b spends at a specified position z in its habitat [8] where: wf are the weighting factors for various components of radiation (low β, β+γ, and α) and are dimensionless.…”

“…Bréchignac et al (6) list a number of sites with particular relevance to the topic of understanding radiation effects on both population and ecosystem levels: accidentally contaminated sites; sites with a high level of natural radioactivity, well-characterised sites which may include: uranium mining sites, gas and oil sites, marine sites receiving exhaust pipes; former nuclear test sites; waste management/waste disposal sites, etc.…”

Fukushima's lessons from the blue butterfly: A risk assessment of the human living environment in the post-Fukushima era

“…The ecological consequences of a nuclear accident are not a linear extrapolation of species impacts. The update to an International Union of Radioecology (IUR) technical statement released in 2011 (Bréchignac et al ) emphasized the IUR's consensus among leading radiation scientists of the importance of ecocentric research reached at the Miami Consensus Symposium (Bréchignac et al ).…”