Anti-inflammatory, therapeutic effects, but also risks – the radioactive noble gas radon contains both at the same time. Radon and especially its short-living progeny are considered to be responsible for about half of the annual radiation exposure from natural sources and are classified as carcinogenic. Researchers from the GSI Helmholtzzentrum für Schwerionenforschung now have proven in a paper published in the “International Journal of Environmental Research and Public Health” that face masks – both FFP2 and surgical masks – strongly reduce lung exposure and thus the dose.