Researchers find short-term radon testing not effective

Many radon test kits wildly inaccurate, study says Watch: A U of C study has found equipment sold in stores to conduct home radon tests is very inaccurate. Kevin Green reports.

Calgary — New research from the University of Calgary finds short-term radon testing kits are not effective.

The findings show short-term tests have up to a 99 per cent failure rate in precisely measuring dangerous levels of exposure to radon gas.

The study finds only long-term testing kits accurately measure exposure to radon gas.

“Radon gas levels can fluctuate wildly day-to-day,” said Dr. Aaron Goodarzi, assistant professor of biochemistry and molecular biology and oncology at Calgary’s Cumming School of Medicine.

“Short-term tests can give a false sense of alarm, or worse, a false sense of security as they cannot precisely predict long-term exposure.”

As awareness has grown about the danger of radon, more people are choosing to test their homes for the cancer-causing gas.

A University of Calgary-led study shows many people may be using test kits that are not accurately determining their exposure to radon.

The research team put a short-term (five-day) test kit, and a long-term (90-day) kit in the same homes. Simultaneous tests were conducted during both summer and winter months.

They found up to a 99 per cent failure rate of the short-term test kits compared to a long-term test.

Radon causes cancer. Health Canada says it is the leading cause of lung cancer in non-smokers.

Radon is a radioactive gas formed by the breakdown of uranium in soil and rock. It is colourless and odourless. Radon is only a concern when it is trapped in confined spaces, such as a house, where it can build to high levels and become a danger to occupants.

On its website, Health Canada recommends testing your home over a period of 91 days or more.

Goodarzi has also been working with the Real Estate Council of Alberta to educate realtors, warning against the use of short-term radon kits as they prepare for the sale of a property.

While there are no official regulations governing radon levels, Health Canada sets an acceptable annual rate of 200 becquerels per cubic metre (200 Bq/m3), while the U.S. rate is 150 and the World Health Organization has proposed recommended levels of 100.

Becquerels per cubic metre (Bq/m3) describes how many radioactive radon particles are decaying every second in every cubic metre of air.

In December 2018, researchers found one-in-eight Calgary homes had dangerous levels of radon gas, while one-in-six homes in the foothills south and west of Calgary were found to have dangerous levels of the gas. The levels reported in the foothills were much higher than those found in the city.

"We have observed houses at 7,199 Bq\m3, which is the equivalent of say 36,000 dental x-rays equivalences of radiation each year," he said at the time.

"Approximately one person a day in Alberta is being diagnosed with radon-induced lung cancer, which is why we're doing this. To understand what makes for a high radon exposure household."

Goodrazi also found the Prairies are home to the second-highest radon exposed population on Earth. The scientist and physician led the Evict Radon research initiative and they are now recruiting participation from across Canada.

"This is easily the most preventable form of environmentally caused cancer. We have already learned so much from the work we’ve done in Alberta to test for and mitigate radon," said Goodrazi.