Six schools exceed proposed radon limits


radon gasSix schools in the Halifax area have had higher levels of potentially harmful radon gas than the new, stricter limits Health Canada is considering.

The schools, among 14 tested in the province for radon gas in 2004, exceeded the proposed advisable limit of 200 becquerels per cubic metre but fell within the current federal guideline of 800, provincial records indicate.

They were: Atlantic Memorial Consolidated in Shad Bay, East St. Margaret’s Elementary in Indian Harbour, Five Bridges Junior High (the former Sir John A. Macdonald High) in Hubley, St. Margaret’s Bay Elementary in Head of St. Margarets Bay, Terence Bay School and William King Elementary in Herring Cove.

Pat Wall, who chairs the province’s intergovernmental advisory group on radon, told a news conference Monday that those tests were shorter-term and the Environment Department is planning to follow up on them.

Mr. Wall said Nova Scotia will investigate radon gas levels at all its schools, hospitals and other public buildings over the next five years. He encouraged homeowners to do the same.

"There is no immediate health risk," Mr. Wall said. "This is not going to kill you tomorrow."

But long-term exposure to the gas, which comes from soil containing uranium and sometimes collects in buildings with inadequate ventilation, is believed to be a second-leading cause of lung cancer after smoking, he said. The risks are even greater for smokers exposed to radon gas.

Higher levels of radon seem to be present in parts of the province south of Halifax, such as Timberlea, Mr. Wall said.

"The only way to tell for sure whether you have radon is to test for it," he said. "You can’t hear it, see it or taste it but it is a radioactive gas."

There are devices people can buy and place in their homes for a period of time to determine if radon levels are safe. They commonly come in the form of small containers that are then sent to a laboratory for analysis, costing $60 to $100.

Mr. Wall said radon gas is only a risk in enclosed areas and typically collects low to the ground, seeping into basements through sewer pipes, crawl spaces and cracks in the walls. The longer time involved in the test, the more accurate it will be, he said.

The province estimates that every year about 40 Nova Scotians die from lung cancer caused by long-term exposure to high levels of radon, Mr. Wall said. The figure is based on a 1997 Statistics Canada study that indicated 1,600 people died countrywide that year from radon-related cancer.

"The risk has not changed," said Dr. Robert Strang, the acting deputy provincial medical officer of health who also represented Nova Scotia on the board that studied the matter for Health Canada. "The risk depends on your exposure."

Alan Thompson, of Inspector Clue-So Home Inspections in Halifax, said he has done about 500 radon tests since 1993, which he doesn’t think is a lot.

"I do the testing but I don’t push it on people," he said.

That’s because it’s difficult to determine for certain that there’s a risk associated with radon levels, he said. But he has had people diagnosed with lung cancer hire him to test for radon and subsequently found the gas was present in their homes, he said.

Mr. Thompson said every home he has tested has at least some radon gas present; homeowners aren’t keen to publicize this information because it could cause their property values to drop.

"The Timberlea area’s through the roof," Mr. Thompson said. "That’s why there was no development out there until recently."

There had been a greater awareness of radon gas prior to this decade, but interest has waned recently, he said.

Test results from 2004, which included 12 schools in Halifax County and two on the South Shore, indicated the following levels of radon gas in a classroom exceeding the proposed limit of 200 becquerels per cubic metre:

  • Atlantic Memorial: 205 / 227 (two classrooms)
  • East St. Margaret’s Elementary: 424
  • Sir John A. Macdonald High: 655
  • St. Margaret’s Bay Elementary: 632
  • Terence Bay School: 246
  • William King Elementary: 327

© 2007 The Halifax Herald Limited 


Previous entry: Cancer Is A Stem Cell Issue

Next entry: Sylicon Valley Moms Blog

Find recent content on the main index or look in the archives to find all content.