A 14-year-old from Louisville, Kentucky, took first place for this radon-awareness poster in a 2015 contest arranged by Kansas State University.

With National Radon Action Month having arrived, Pitkin County and Aspen environmental health officials are issuing reminders about the dangers of the odorless, colorless, radioactive gas — and how local property owners can take steps to lessen its threat to health.

“You’ve got a 50-50 chance of having a lung-cancer risk factor in your home,” Jannette Whitcomb, senior environmental health specialist for the city, said in reference to radon. “But this is a risk factor that you can correct.”

Whitcomb and Pitkin County environmental health specialist Bryan Daugherty say plenty of free testing kits are available to local residents who want to see whether dangerous levels of radon exist in their homes. The kits can be picked up at the county administration building, 530 E. Main St., Suite 205.

Radon is formed by the natural radioactive decay of uranium in rock, soil and water. It can be found in all 50 states, but Colorado is said to have one of the highest national rates of radon gas seeping into homes due to the presence of uranium beneath the land and its history of uranium mining.

Whitcomb estimates that since the city stepped up its awareness of the dangers of radon some 10 years ago, about 700 houses have been tested in the city, with results showing a little more than half of the homes containing high levels of the gas.

While long-term radon exposure can lead to lung cancer, and possibly death, it’s not considered as dangerous as nicotine consumption through smoking, Whitcomb said. But those who smoke while also living in homes with high levels of radon face an increased health threat, according to Daugherty.

“Smoking and radon exposure together are much worse than just smoking or just radon,” he said.

Both the city and the county have received $5,000 grants from the state for the purposes of conducting a media campaign about the need for radon testing early this year, Whitcomb said. The two governmental entities will coordinate their efforts so that they don’t overlap.

Daugherty said the county distributes about 150 kits per year, and that in recent years about 400 to 500 homes have been tested in the county. He concurred with Whitcomb’s statement that roughly half of the tests show higher-than-acceptable levels of radon in local homes.

“Anywhere in our county can be testing high,” he said.

Because radon is heavier than air, it can accumulate in the lowest portions of a house, such as basements, crawl spaces or other low-lying areas. Homes with central heating may have an increased presence of the gas because such systems may draw air from basements or crawl spaces.

“The more you’re exposed to radon the more likely you’re going to be contracting lung cancer,” Daugherty said.

Mitigation can be somewhat expensive, running into the thousands of dollars, Whitcomb said. The process isn’t complicated, Daugherty said, and it involves sealing off cracks in low-lying areas of a house and then using a fan to draw out the air and send it outside.

“It all depends on the house,” he said of the mitigation costs.

The best time of year for radon testing is winter, said Whitcomb, because that’s when people tend to keep their houses sealed from outdoor elements. The reading of radon levels tends to be more accurate during winter months.

“Winter testing is going to give you the worst-case scenario for your home,” Daugherty said.

He said while radon exposure can cause lung cancer, it’s difficult to accurately connect radon to actual cancer cases. People might be contracting lung cancer though other ways as well, such as smoking and asbestos exposure, or a combination of the two or three factors.

Whitcomb added that even the health of pets can be affected by high levels of radon within a home.

Andre is a reporter for Aspen Daily News. He can be reached at andre@aspendailynews.com.