Uranium is a radioactive substance that breaks down into radioactive radium, which, in turn, is broken down to the radioactive gas Radon. Radon is a colorless, odorless, radioactive gas that may cause lung cancer.
The more uranium and radium there are in the ground, the more radon is formed. Hence, an area with a lot of uranium in the ground, is an area that can be radon exposed. Alun slate and uranium rich granites are typical uranium rich rocks (Source: Norwegian Radiation Protection Authority)
It’s estimated that approximately 1 million buildings in Norway have higher radon levels than recommended by the authorities. (Source: Norwegian Radon Association)
The risk of catching lung cancer due to radon, is 20-25 times higher for smokers than for those that have never smoked (Source: Norwegian Cancer Society).
Radon increase the risk of cancer and is after smoking, the main reason for lung cancer according to WHO. Norway is among the countries in the world with the highest concentration of radon gas in the indoor air. This is among other due to our geological and climatic conditions (Source: Norwegian Radon Association)
1 out of 10 households in Norway has radon levels that is too high and yearly 300 people dies of lung cancer due to radon exposure. Nevertheless, the knowledge about the radioactive gas is low. Half of the municipalities in the survey, conducted by the Radiation Protection Authority, have no program for information about radon, and the radon risk are not considered in municipal regulatory plans.
Radon increases the risk of lung cancer. The risk increases proportionally with the Radon exposure. Any reduction of radon concentration in indoor air will therefore have a positive health effect (Source: Building Quality Directorate)
Radon causes lung cancer, and the risk increase from the radon concentration in the indoor air as well as the duration of exposure. There is no lower threshold value for when radon is harmful. Former and active smokers is at a higher risk as the radon exposure is more than 20 times higher for smokers than for those that have never smoked. Nevertheless, the risk for non-smokers are also considerable.
To reduce the risk in existing buildings, radon reducing measures can be implemented. By halving the radon level, the risk of developing lung cancer due to radon is also halved (Source: Norwegian Radiation Protection Authority)
Why is radon dangerous?
Several short-lived radionuclides called radon daughters, are formed continuously when it is Radon in the air. Both radon and radon daughters emits alpha radiation, and can harm living cells so that some can develop into cancer cells. Alpha radiation does not penetrate through the skin, but the risk for developing lung cancer can increase by inhalation. Radiation doses to other organs other than the lungs, are very limited and can be disregarded (Source: Norwegian Radiation Protection Authority)