Professor Nick Beresford (@Radioecology) of the Centre for Ecology & Hydrology led the TREE (Transfer-Exposure-Effects) project, an international collaboration to investigate how to reduce uncertainty in estimating the risk to humans and wildlife of exposure to radioactivity. A major part of the project was fieldwork undertaken in the Chernobyl Exclusion zone.
Scientists from the project met in Portsmouth recently to discuss the research to date and the next steps for their work. Nick tells us more...
Releases of radioactivity, whether authorised (from the nuclear power industry, hospitals and research establishments), or accidental, need to be assessed with respect to their potential impacts on wildlife. This is a relatively new requirement which has evolved over the last two decades; hence the underpinning science is still developing. As part of any environmental protection framework we need to understand the effects of radiation on wildlife.
The large area around the Chernobyl nuclear reactor, abandoned in 1986 after what remains the world’s worst nuclear accident, offers us the opportunity to study the impacts of radiation on wildlife in the environment.
The amazing story of Przewalski's horse in #Chernobyl. Released in the 1990s, these beautiful animals have thrived in the Zone. They use abandoned collective farms as their stables and their numbers have increased dramatically over the last 2 decades.@radioecology @CEHScienceNews pic.twitter.com/CJDLD9jMiE— Prof Mike Wood (@ProfMikeWood) March 4, 2019
Results from studies conducted in the Chernobyl Exclusion Zone (CEZ) are conflicting, however. Some groups, for example, have suggested significant impacts at very low exposure rates. Such results have received relatively high media attention and are used to challenge regulators and relevant international bodies.
Over the last five years, the CEH-led TREE project, funded under the RATE programme, has conducted research in the Chernobyl Exclusion Zone. At the same time we performed controlled laboratory studies on similar organisms to those studied in the field.
The project represents the largest co-ordinated study of the effects of radiation on wildlife ever conducted in the Chernobyl Exclusion Zone. As TREE comes to a close, we held a workshop together with the European Radioecology ALLIANCE to share our findings and discuss priorities for the future. The workshop was attended by scientists from the UK, Ireland, France, Belgium, Spain, Ukraine, Norway and the RATE programme funders (NERC, Radioactive Waste Management Ltd. and the Environment Agency).
"The TREE project represents the largest co-ordinated study of the effects of radiation on wildlife ever conducted in the Chernobyl Exclusion Zone"
Over the course of the workshop, we heard 25 presentations summarising findings about the effects of radiation on a range of wildlife from soil biota, plants and bumblebees to fish, birds and mammals. The breadth of studies, and the use of different technologies such as drones, camera traps and acoustic recordings, was a hallmark of the TREE project. We also had robust discussion sessions about the science to date.
Results from TREE show no evidence of radiation effects on wildlife at dose rates typical for permitted discharges in the UK. However, while wildlife at Chernobyl appears to be thriving, radiation effects are observable in some species in the most contaminated parts of the Chernobyl Exclusion Zone.
Kat Raines @anchorage40 showing great lab and field studies on bumblebees reporting negative interactions between radiation levels and parasite burden. Also reduced age in bumblebees from contaminated areas.@CEHScienceNews pic.twitter.com/iGF0K3wYvi— Germán Orizaola (@GOrizaola) March 5, 2019
Our results also suggest that internal benchmark dose rates need to be reviewed. The workshop highlighted the difficulty of interpreting results from the Zone – are effects due to current chronic exposure rates, the effect of habitat or a residual impact of earlier much higher exposures?
Participants agreed to establish a meta-database of Chernobyl field sites to better share data and also prepare a statement paper on research priorities with respect to the impacts of radiation on wildlife, best practices for studies and data reporting, and the use of the Exclusion Zone in future research.
Important idea from Sergey Gaschak about #Chernobyl future: It’s crucial to preserve the inviolability of the large size of the Exclusion Zone as a biodiversity reserve if we want to maintain populations of many endangered animals.@CEHScienceNews pic.twitter.com/eOjv8vCnpz— Germán Orizaola (@GOrizaola) March 5, 2019Knowledge exchange has been a vital aspect of TREE’s work and was instrumental in us being awarded the Times Higher Education Project of the Year 2016. The sharing of ideas and the spirit of collaboration seen throughout the project was reflected again at the Portsmouth workshop. One participant commented that the workshop was a “supportive balance of constructive criticism and friendly advice that is often sought and rarely seen.”
This ensures we are in a good place to establish future research priorities and advance the field of radioecology in collaboration with our European colleagues.
For more information on research in Chernobyl, see: Field effects studies in the Chernobyl Exclusion Zone: Lessons to be learnt.