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Does radioactive gas lurk in your home?

by: COURTESY OF PORTLAND STATE UNIVERSITY DEPARTMENT OF GEOLOGY  - Researchers can now map average radon contamination levels by ZIP code, based on data from thousands of home radon tests. Levels vary from from home to home, so some properties in low and moderate areas may be alarmingly high. A tasteless, colorless, invisible killer can be detected in one in four houses in the Portland metro area. Its name is radon, a radioactive gas, and experts say the time to test for it is now.

“I don’t want to sit here 30 years later from now and learn my husband has cancer,” says Ella Vining, a mother of two from Southeast Portland.

Her husband’s office is in the basement of their home, and an initial radon test showed moderate levels of the radioactive gas in the basement.

Basements are usually the key site of exposure, because radon seeps in from the soil below.

A research team led by Portland State University geology professor Scott Burns, which tracks radon exposure levels statewide, updated its previous maps in January, based on a surge of new data derived from test results from 33,000 homes. The new data enabled the team to map out levels of radon by ZIP code across the state.

Researchers documented elevated radon levels in several parts of Portland, plus Banks, Boring, Clackamas, Gladstone, Lake Oswego, Sandy, Sherwood and Wilsonville. Outside the Portland area, there were elevated radon levels in Astoria, Milton-Freewater, Myrtle Creek and Silverton.

Contamination can vary from house to house, Burns cautions, so even an area that has low predicted radon levels may register radon levels in the moderate range or higher.

If untreated, the effects from prolonged radon exposure can be fatal.

Radon causes about 21,000 deaths per year in the United States — twice the number who die from drunken-driving incidents. It’s the No. 1 cause of lung cancer in nonsmokers.

Luckily, there are ways to test for radon.

New results raise alarm

Manufacturers of test kits record the radioactive levels measured by users, and send some of the data to the state. The Oregon Health Division gives the data to Burns and his team, which they organize by ZIP code.

In 1994, Burns and his team started research with data from only 1,100 houses. By 2003, they had test results from 3,500 houses. Since January, they’ve had much more extensive statewide testing results, with data from 33,000 additional homes.

“Two-thirds of the tests were in high- or moderate-potential areas for radon poisoning,” Burns says. “We are trying to get people who are in areas that are high and moderate to test their homes.” (See accompanying map of Portland-area ZIP codes).

The ideal time to test is in the winter, but “you don’t want to wait six months to find out if there’s radon in your house,” says Chad Ruhoff, who does radon testing and mitigation for the Neil Kelly home-remodeling company in Portland.

Levels of concern

There are three levels of radon exposure typically used:

• Low: less than two picocuries per liter

• Moderate: two to four picocuries

• High: more than four picocuries

Vining’s basement registered 3.7 picocuries, in the moderate range, but still of concern. The family opted to remove the radon, a process known as mitigation.

For Ruhoff, the choice to pay for mitigation work was easy. He tested for radon in his own home five years ago, when Neil Kelly hired him. He found his house registered six picocuries per liter — higher than the four picocuries level that the U.S. Environmental Protection Agency defines as acceptable. His children’s playroom and art room were located in the basement.

“I don’t want them exposed to that gas,” Ruhoff says.

There are both short-term and long-term test kits. The short-term test measures radon levels in a house during the past two days to three months. A long-term test measures levels from three months to a year or more.

Neil Kelly likes to take an average radon exposure level over the course of a year, Ruhoff says. The company starts with a short-term test, and then determines whether another short-term or long-term testing is required, or if mitigation should proceed.

Prehistoric flooding is culprit

The radon problem here originated with the Missoula Floods during the Ice Age. Flood waters carved the Columbia River Gorge and brought an unwelcome intruder: radioactive radon embedded in granite. As a result, there are high levels of radon in flood-deposit areas, Burns says.

“We didn’t know it was a hazard till 1984,” he says.

Then-U.S. Surgeon General Richard Carmona warned the public about the dangers of radon in 2005, calling the threat “completely preventable.”

Radon seeps into a home because of pressure the house puts on the soil below. To ease the pressure, mitigation companies seal up cracks in the basement. Then a four-inch-diameter hole is cut into the basement floor, and an area of the ground below is cleared out. A pipe is attached from the hole up to the roof with a pump to filter air out of the house.

This entire process can cost from $900 to $2,500. At Neil Kelly, a standard mitigation job costs about $1,500, depending on the complexity of the house.

During mitigation, workers don’t generally wear special protective gear to avoid inhaling radon, Ruhoff says.

“Radon poisoning is from long exposures and high levels,” he explains. For example, someone living in a basement bedroom with high radon levels might be exposed for eight hours each night.

Vining and her family live in the 97202 ZIP code, which includes Sellwood, Eastmoreland, Brooklyn and nearby neighborhoods. Burns’ team now has test results from 348 properties in that ZIP code, with an average result of 3.8 picocuries. Though that average places the ZIP code in the moderate category, 31 percent of the tests there registered levels higher than four picocuries.

Testing conducted after the Vinings had their problem mitigated last January showed a radon level of 0.9, which Ruhoff says is better than the air outside.

“It’s something I don’t have to worry about now,” Ella Vining says. “And if we put our house on the market one day, I think it’ll help.”

During his time with Neil Kelly, Ruhoff says there’s been an increase in the number of people testing and mitigating for radon.

But Burns says there’s plenty more in need of mitigation.

“The object is to encourage those in areas where we are without data points to get a kit,” Burns says. “We need 10 houses in one ZIP code to have data.”

He advises people to test twice and place the kit in a closet that doesn’t get a lot of air circulation, and not to test in a bathroom or kitchen.

The American Lung Association sells short-term radon test kits for $14 at www.radonkit.org.

“It’s not going to break the bank for something that could be a big issue,” Ruhoff says.