No safe levels for invisible, odourless gas
Radon, a heavy gas formed when uranium in the ground breaks down, enters people's homes through cracks and openings in the foundation.
The gas is radioactive, and is responsible for 847 lung cancer deaths in Ontario each year, about 14 per cent of all fatalities related to the disease.
Michael King, an epidemiologist with the Sudbury and District Health Unit, said 90 per cent of cancer deaths from radon happen to people who are also smokers.
King, who spoke about the health risks associated with radon at an air quality seminar presented by the Sudbury Lung Disease Support Group, said radon's effect on the lungs is cumulative if a person also happens to be a smoker.
“Any level of radon can cause lung cancer,” King said. “There is no safe level of radon.”
Health Canada says a radon concentration exceeding 200 becquerels per cubic metre should be of concern for homeowners. A becquerel measures the amount of radioactive activity in a location.
Health Canada has calculated about five per cent of Sudbury homes exceed radon measurements of 200 becquerels per cubic metre. About one per cent of homes exceed the very high level of 600 becquerels per cubic metre.
King said the number is low, compared to other Canadian jurisdictions – such as the prairies – but recommended homeowners test the radon levels in their homes.
The average radon concentration outside, where the gas can disperse, is about 10 becquerels per cubic metre.
King said homeowners can purchase a radon test kit for less than $100. It takes about three months for the kit to get an accurate average radon level reading, he said.
Because radon is a heavy gas, it is more prominent in basements and lower floors, and not a problem for people who live in apartments at upper levels, King said.
To reduce a home's radon levels, he said, it is possible to seal cracks in a home's foundation. A homeowner can also improve their home's ventilation, to let in outside air that would have lower concentrations, and release air from the inside.
But the most effective way to reduce a home's radon concentration is to hire a contractor to install a sub-slab depressurization system, he said. The system consists of pipes installed in the house's substructure that divert the radon to the surrounding air.
The cost to install a sub-slab depressurization system ranges between $2,000 and $3,000, King said.
Brenda Stankiewicz, a public health nurse with the health unit, spoke about the impact smoking cannabis has on the lungs during the seminar.
Stankiewicz said marijuana is just as dangerous as tobacco, when it comes to its effect on the lungs.
“The same cancer-causing chemicals that are in marijuana when it's inhaled, are in tobacco,” she said.
There are 400 chemicals found in marijuana smoke, and about 4,000 in cigarettes, she said.
In addition to its impact on the lungs, Stankiewicz said there is a strong body of research that has linked early use of marijuana, before adulthood, to an increased risk of psychosis and schizophrenia.
“Marijuana is an illegal substance,” she said. “So you shouldn't be possessing it in the first place.”