materials and technologies, knowledge of behaviour patterns of the occupants, including use of consumer products, as well as energy and sustainability policies.
Regulators, as well as many scientists, didn’t take much notice of contaminant intrusion until the 2000s. At that time, awareness had grown about the hazards of radon. The average person is not likely to detect radon intrusion. You need sophisticated instrumentation to measure low concentrations that are involved.The World Health Organization concludes that radon causes lung cancer in Europe, North America and Asia. The analyses assume that the lung cancer risk increases proportionally with increasing radon exposure.
This assumption has been questioned. As many people are exposed to low and moderate radon concentrations, the majority of lung cancers related to radon are caused by these low exposure levels rather than by higher concentrations (WHO). Most of the radon-induced lung cancer cases occur among smokers due to a strong combined effect of smoking and radon. WHO proposes a reference level of 100 Bq/m3 to minimize health hazards due to indoor radon exposure (WHO). However, if this level cannot be reached under the prevailing country specific conditions, the chosen reference level should not exceed 300 Bq/m3.
Indoor radon pollution mapping in dwellings
In 2006, the Joint Research Centre of the European Commission launched a project to map radon at the European level, as part of a planned European Atlas of Natural Radiation starting with a map of European indoor radon concentrations. Although a few uninhabited areas remain, the reason for which is that radon surveys are still ongoing, or national surveys have concentrated on high-radon areas.
Almost all European countries have monitoring programmes for radon. Clearly, radon monitoring and reduction strategies are best developed in countries with an established radon problem. Radon mitigation in these countries includes national information systems, guidance documents for buildings and local and national radon maps.
The majority of European countries do not have different policies for the various population groups — only a few countries make distinctions between children and the rest of the population by establishing lower reference levels for radon in schools and kindergartens or offering additional financial support for remediation to reduce children’s exposure.
The European Commission issued a Recommendation (EC, 1990) on the protection of the public against indoor radon exposure (90/143/Euratom) in order to harmonize Member States’s provisions for the application of the basic safety standards for health protection against the dangers arising from ionizing radiation. This Recommendation gives guidelines for public information, an indoor radon reference level, an annual average concentration of 400 Bq/m3 applicable for existing dwellings; and design levels of an annual concentration of 200 for future construction, above which remedial actions and preventive measures should be considered.
In addition to reference levels for indoor radon concentration in workplaces (1000 Bq/m3) and dwellings and buildings with public access (300 Bq/m3 for existing, 200 Bq/m3 for new ones), the Euratom Basic Safety Standards foresees obligating EU Members to establish a radon action plan, aimed at managing long-term risks of radon exposures in dwellings, buildings with public access and workplaces for any source of radon ingress, whether from soil, building materials or water. JRC has prepared a map on indoor radon concentration and is currently trying to produce a European geogenic radon map.
A geogenic map has been produced and a first trial version was presented at the 11th International Workshop on the Geological Aspects of Radon Risk Mapping held in Prague in 2012. After that the JRC has created a more comprehensive geogenic radon database asking the participating countries to supply radiometric data related to radon. Nowadays, the range and distribution of indoor radon levels in other countries, such as the US, have been quantified and scientifically measured by national surveys.
Don’t worry. You can still rent a house for your holidays even abroad. The risk from radon is on the basis of a lifetime spent in the same house. Some experts argue that small doses of radiation may even be good for us, stimulating our immune defences. But if they invite you to try, politely decline: “I am trying to give up smoking. Radon, at least”.
Eusebio Loria
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