How to protect against low-level radiation
There are many radiation sources, usually in low doses, from key medical diagnostic equipment to natural sources like radon gas that emanates from the ground. Until now, there has been little understanding of the low-dose radiation impact, but a European research project, DoReMi, is examining the potential health risks and how to protect against them.
The project team gathers biologists, radiation specialists and other experts in promoting low-dose risk research. “Exposure to natural radiation is to some extent unavoidable, while medical exposure during diagnosis and therapy is now an indispensable part of modern medicine,” says DoReMi coordinator Sisko Salomaa, who is also the Research Director of Finnish Radiation and Nuclear Safety Authority (STUK). “We want to ensure a robust radiation protection system that has a sound and up-to-date scientific basis,” he adds.
Part of the project challenge is that, although there is plenty of publicly available information on radiation, it may be difficult for an individual citizen to judge what is reliable. This communication gap is one reason why the DoReMi research work is closely linked with education and training, thus fostering the next generation of radiation scientists in Europe.
Since epidemiology – the study of disease patterns - does not explain radiation and cancer risks at low doses, new modelling approaches are needed to better understand, in quantitative terms, what the risks in the low-dose range are. “Our radiation protection system is designed to provide protection to an average individual. Yet we are aware that there are some differences between individuals,” says Salomaa.
DoReMi’s research strategy includes exploring new scientific approaches, such as epigenetics (the study of how individual genes affect the overall genetic outcome) and stem cell research. The research activities are all performed at appropriately low-doses. “We are now gaining an understanding of the link between radiation doses and the protein changes associated with ageing cells,” explains Salomaa.
One key issue concerns radiation’s non-cancer effects. Recent observations indicate that dose thresholds for cardiovascular disease and lens opacities are lower than previously assumed. DoReMi project team has helped develop novel approaches to explore potential biological and physiological effects, and its studies confirmed that there indeed might be a low-dose radiation risk for lens opacities or cardiovascular disease several decades after the exposure.
DoReMi project has already paved the way to the Multidisciplinary European Low Dose Initiative (MELODI), a platform of 22 European agencies and institutes that will develop and coordinate scientific policies. The project has also led to OPERRA, which links low-dose risk research community with experts studying how radioactive substances interact with nature, and with organisations developing tools for emergency preparedness.
The DoReMi team points out that the radiation protection system is ultimately based not only on science but also on practical experience. “We are proud of the way we have been able to engage the wider scientific community in the brainstorming on the research agenda and the roadmap for further research,” says Salomaa. “Even after decades of research we may not understand all the details of the relevant biological effects, but we are confident that we will understand much better where weaknesses of the radiation protection system are and what we can do to make it more robust,” he concludes.