Radon is a naturally occurring radioactive gas created by the breakdown of uranium in the ground. Radon is colourless, odorless, and tasteless. In the open air, radon poses limited health risks, as radon escaping from the soil is diluted in the open air. However, in confined spaces, such as homes, radon can build up and become a health hazard. Exposure to high levels of radon has been associated with an increased risk of lung cancer. In Canada, radon is the second leading cause of lung cancer after tobacco smoke.
The risk of health effects from radon depends primarily on:
- Radon concentration
- Duration of exposure
- Smoking habits or exposure to second-hand smoke
Smokers are at significantly higher risk of developing lung cancer when exposed to radon. A non-smoker exposed to radon has a lifetime lung cancer risk of 1 in 20. A smoker NOT exposed to radon has a lifetime lung cancer risk of 1 in 10, whereas a smoker exposed to radon has a lifetime lung cancer risk of 1 in 3.
Radon gas can enter your home through cracks in the basement, sump pumps, floor drains, or any other opening where the house contacts the soil. The Canadian guideline for radon levels in indoor air is 200 Becquerels* per cubic meter (Bq/m3).
*A Becquerel equals one radioactive disintegration per second.
The age or location of a house can’t predict the level of radon. Radon concentration will vary from home to home, neighbour to neighbour. Any house could be at risk. The ONLY way to know the radon level in your home is to test.