Tests show high levels of radon in Thunder Bay-area homes

Eco Superior says high radon levels have been discovered in a large number of homes located outside of Thunder Bay city limits.

Radon, a known cancer-causing agent, can be mitigated by filling basement floor cracks or covering sump pits

Homes outside the Thunder Bay city limits have tested higher than the national average for radon— an odourless, colourless gas. (CBC)

High levels of radon — a naturally-occurring, but cancer-causing radioactive gas — have been discovered in a large number of homes located outside of Thunder Bay city limits, according to EcoSuperior.

The environmental group says it recently compiled the results of people who bought home radon test kits.

Results showed that 42 per cent of homes tested outside of Thunder Bay were above Health Canada-recommended levels, and much higher than the national average, said Caroline Cox, a program coordinator for EcoSuperior.

"We know that on a national scale, 6.9 per cent of homes will test high for radon," Cox said.

"So high means above the Health Canada recommended guideline of 200 becquerels per metre cubed.  So that is very concerning."

Cox said high levels of radon come from uranium breaking down in the soil. Its entry into a home can often be mitigated by filling a basement floor crack or covering a sump pit.

While the tests were conducted in homes in communities ranging from Sioux Lookout, Ont. east to Longlac, EcoSuperior said that the "vast majority" were conducted in the municipalities surrounding Thunder Bay.

High levels of radon were detected in homes in Neebing, Gorham, Murillo, Kaministiqua, Shuniah, Rosslyn, and Kakabeka Falls, according to the environmental group.

In September, the Thunder Bay District Health Unit also said it would expand testing to homes in other northwestern Ontario communities.

Eco Superior will be holding a radon workshop Nov. 21,  in Thunder Bay, at the Waverley Resource Library from  6:30 p.m. to 7:30 pm.


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