Radon is a radioactive noble gas that comes from the breakdown of uranium in soil, rocks, and water. It emits alpha radiation and is odorless, tasteless, and invisible. Once released into the atmosphere, radon breaks down into radioactive elements which when inhaled causes damage to lung tissue which leads to lung cancer.
Radon dilutes very quickly and is typically not a problem outdoors, however in buildings radon gas becomes enclosed and accumulates into high levels which are harmful to humans and animals.
In Canada radon is measured in becquerels per cubic meter (bq/m³). A becquerel is referred to as one radioactive decay per second. This means if you tested your home and the results came back at 200bq/m³ that means for every cubic meter of air, there are 200 radioactive decays per second.
Radon concentration levels will vary from one house to another, even if the buildings are similar designs and next door to each other. No matter the age, type of construction, or where your home is located, the only way to ensure you have safe levels of radon gas in your home is to test for it.
In this video Aaron Goodarzi explains the science and the long term health effects radon has on the human body.
There are many ways radon can enter into your home. Radon moves through any opening that is in contact with the ground. Crawl spaces, small cracks, openings in the foundation, poorly sealed windows, sump pits, waste drainages, and fittings all create openings for radon to gas to enter. Typically the air pressure in the soil surrounding your home is higher than inside the building. The difference in pressure then draws radon gas into your home while it tries to reach equilibrium. Radon is also found in water, most commonly in wells in rural municipalities.
Radon impacts your health by decaying into radioactive decay products that are easily inhaled and deposited in the lungs where they emit radiation and damage sensitive lung tissue.
According to Health Canada, radon gas is responsible for 1 out of every 6 lung cancer deaths and is the leading environmental cause of lung cancer.
Exposure to high levels of radon and the use of tobacco together significantly increases your risk of lung cancer. If you are a lifelong smoker your risk of getting lung cancer is 1 in 10. If you add long term exposure to a high level of radon, your risk becomes 1 in 3. As a non-smoker, your lifetime lung cancer risk, at the same high levels of radon are 1 in 20.