Long-term exposure to radon gas is the second-leading cause of lung cancer in the United States, according to the U.S. Environmental Protection Agency. Studies show that Madison County is second only to Colbert County for the highest levels of radon in Alabama.

From New Market to Madison, from Florence to Scottsboro, bits of uranium line the Chattanooga shale formations underfoot. As the heavy metal decays, gas escapes. The radioactive emissions seep through caves and fissures and sidewalks to drift away harmlessly.

Enter climate control, weather stripping, double-pane glass, caulking and storm windows.

If the pathway through the ground ends in a basement or crawl space, gas can become trapped and pool in the atmosphere of the home or building above.

Radon is colorless and odorless. It has no taste. There are no known symptoms of early exposure. Related lung cancer may not set in for five to 20 years after exposure.

"The only way to know is to test your house," said James McNees, head of the state's radon program at the Alabama Department of Public Health. "The problem is easy to fix."

How radon gets in The major cause of radon entering a building is the small difference between inside and outside pressure. It works the same way a fire draws air up a chimney. A heated house draws cool air from the basement or ground floor where the pressure is low and sends it to the upper floors where the pressure is higher.	Where it comes from Radon is an odorless, colorless radioactive gas that is made by the natural decay of radium and uranium found in rocks and soil. Radon breaks down into harmful elements that attach to dust particles and can enter the lungs. There the elements decay in minutes, releasing alpha radiation. This radiation can cause cell damage possibly leading to cancer.

In New Market, Bott-Jenkins worries the well-being of her children demands more than $1,500 in repairs she says she can't afford.

That's money she says she doesn't have. That's money she says the government ought to provide. After all, she argues, the federal government acknowledges the problem, the state government knows the dangers and local government sets the building codes. She called the Federal Housing Authority, the county extension systems, the state Department of Public Health to ask for help.

"The Health Department doesn't have any money to help you," McNees said. "I'm sorry."

He said the money the state does have mainly comes from federal grants and goes toward radon awareness and testing. Repairs rest with homeowners.

He said radon rates in Alabama are high in 15 counties where uranium lines shale or granite formations and where caves provide opportunities for radon to reach the surface.

Last week, McNees gave a plaque and commendation to Adams Homes in Huntsville. Last year, the company voluntarily decided to begin installing radon ventilation stacks in all new homes. As awareness spread, the company had begun to see more requests for radon tests from Realtors, sales manager Barbara Breland said.

"I think it's something that's probably going to come eventually in the codes," Breland said. "You want to please your customers and I guess we stepped up and got on the front of this thing."

The Decatur City Council changed its construction code and began requiring the slender ventilation stacks a couple of years ago. In May, the Federal Housing Commission required a radon agreement and notification in the contract of all HUD-acquired homes. In Huntsville, where levels can be high throughout town, the city has no standards.

Barry Crumrine, assistant director of city inspections, said the city still operates under building codes passed in 1979.

Dale Shepherd is familiar with the problem and familiar with the lack of knowledge.

Shepherd baby-proofs homes as part of the Waxing Moon Baby Safety Solutions business. That includes bringing in a 14-by-14-inch cube with a vacuum chamber.

"Every house that I've checked has had elevated radon levels to one extent or another," said Shepherd, who has done about 15 homes in Madison County in recent months. The EPA recommends homes have less than 4 picoCuries per liter of air. He finds levels two and three times that. He tested one home at 65 picoCuries.

"They just look at me and blink. They kind of know it's bad. But they don't even know what it is."

That's where the mitigators come in. There are a few listed in the Huntsville phone book under radon. Ken Lightsey and Tennessee Valley Home Inspections covers a broad swath of homes from Florence to Huntsville.

He sees rates of 30 and 40 picoCuries. The EPA says that when rates get above 20, about 36 in 1,000 non-smokers will get lung cancer. At that same high exposure, one in four smokers would get lung cancer.

Lightsey brings the rates down. He drills through the concrete slab under a home and digs a small depressurization pit beneath that slab. The gas will gather in the empty space. He then runs a thin PVC pipe from that pit to the roof. A small fan continuously draws the gas up the tube and away from the house.

Average costs range from $1,000 to $2,000. Prices depend on the type of foundation and placement of the exhaust pipe. "Good mitigators work with the homeowners to find the least intrusive placement," he said.

Levels can vary greatly between next-door neighbors. No type of foundation offers better protection than another.

To test a house, homeowners here can go to the building at 819 Cook Ave. behind Krispy Kreme on North Memorial Parkway and ask for Walter Rodgers. He handles radon education for the local office of the Alabama Cooperative Extension System. It sells $5 test vials. He said after 48 hours, homeowners can put the vial back in the box and send it to a lab for no additional charge.

He said agents in 16 counties sell more than 1,000 tests each year, although the kits can also be found at hardware stores.

In New Market, Bott-Jenkins has been running the tests and struggling to connect the dots. The family's 62-year-old nanny lies on a respirator in a nursing home in Ohio. Her 4-year-old needs a nebulizer and an asthma inhaler. So does the 6-year-old. No one in the family smoked. She suspects that radon could be the cause.

She shows a recent test that measured her radon level at 22 picoCuries, or more than five times the recommended levels.

Groups ranging from the EPA to the U.S. Centers for Disease Control to the American Medical Association agree radon can drop radioactive particles in the lungs that cause cancer. EPA estimates 21,000 lung cancer deaths in the U.S. each year are due to indoor radon. "There is no evidence that other respiratory diseases, such as asthma, are caused by radon exposure," reads the EPA Web site.

But a basic fact sheet posted by the Centers for Disease Control, says "exposure to high levels of radon may result in an increased incidence of lung disease, such as emphysema and pulmonary fibrosis." These findings are based on studies of miners and animals, rather than the residential samples that link radon and lung cancer.

As far as a link to asthma, "no one's really thought to look for it. They've really only known about this for less than 20 years," said Dr. Richard Spera at the Alabama Infectious Disease Center.

Spera said that emphysema and related conditions are more closely linked to smoking than radon. The causes are less clear with pulmonary fibrosis. "There are a lot of things that are possible, but the one with the most data to support it is lung cancer," he said.

Apparently, it's difficult to conduct definitive long-range studies on radon because people move, there is little historical record-keeping on radon rates and studies must consider everything from smoking to exercise to how often someone closes the windows.

Spera compared radon to a bad diet or a pack-a-day habit - a health problem with a ready solution. "They need to be aware of it. I wouldn't go and sell my house if it had radon in it. I would take proper steps to make sure it's vented."

At Bott-Jenkins' home, a trampoline rests in the side yard, pumpkins line the front porch and homemade wood cuts of the Ten Commandments perch alongside the patio door at the end of the driveway.

She begins to point next door, where the neighbors moved to avoid the cotton defoliant sprayed in fields down the road. She says a neighbor recently died of lung cancer, although he didn't smoke.

Many of her suspicions are unproved. Even if many elderly neighbors have respiratory illness, there is no easy way to link each case to radon.

"I think this is not just my problem. The New Market people do not realize how bad radon is in this area," she says. "I think the government needs to do something. They can't just keep letting people die like this."