Warning on Radon Released : Health: A study says homes in three area communities may contain an unsafe level of the cancer-causing gas.

People who live in or near Simi Valley, Fillmore and Westlake Village have a higher than average chance that cancer-causing radon gas is present at unsafe levels in their homes, according to a state study released Tuesday.

On average, one in 100 Californian homes have elevated radon levels above four picocuries per liter of air, the study says. Living in a home with that level of radon is the equivalent of smoking about half a pack of cigarettes a day, officials say.

The study found that in and near Westlake Village and Agoura Hills, just east of the Ventura County line, elevated radon levels can be expected in 14% of homes. In Simi Valley and Fillmore, elevated radon levels were found 8% of the time. And in the rest of the county, radon levels were elevated in 1% to 2% of the homes.

The EPA estimates that 13 to 50 of every 1,000 people exposed to unsafe levels of radon over a 70-year period could die of lung cancer.

Radon, which is present in soil everywhere, is produced by the natural decaying of uranium.

The California Department of Health Services, which compiled the study, recommends that residents in areas with higher than normal incidences of radon test their homes for the radioactive gas, which seeps into residences through foundation cracks and other crevices.

But the American Lung Assn., which lists radon as the leading cause of lung cancer among nonsmokers, recommends that residents countywide purchase a low-cost kit to test their homes for the deadly gas.

“Radon causes lung cancer because it gives a little dose of radioactivity directly onto the lung,” said Dr. Paul Papanek, president of the Los Angeles County chapter of the American Lung Assn.

“If you’re going to live in a home with your family, it makes good public health sense to find out if you’re exposing them to radon.”

The test kits are available at three area stores for $35 or less. Once detected, radon exposure can be reduced to very low levels with improvements costing from $500 to $5,000, county and state officials said.

Over the past year, the state Health Department studied radon monitors in 862 houses in Ventura and northwestern Los Angeles counties. Because the study used ZIP codes to mark geographical areas--an arbitrary boundary in geological terms--state officials stress that the lines are not absolute.

Radon emanates from geological deposits such as shale beneath the floors and foundations of homes and buildings. The gas is sucked into the residence when a vacuum is created by warm air escaping through the roof or by exhaust fans such as those in the kitchen or bathroom.

Levels of radon could be elevated in Ventura County because layers of gas-producing sediment are not as deep in the earth as they are in other areas of California, according to county health officials.

Homes built on concrete slabs, as are an estimated 65% of homes in California, tend to have higher levels of radon than those built with a crawl space beneath, said David Quinton, environmental health specialist with the state Health Department. The crawl space allows for better ventilation underneath the house, he said.

Apartments on higher floors also have reduced risk of radon.

Older houses tend to have higher levels than newer homes because they have had more time to develop cracks.

But regardless of how the home is built, it can be fixed, Quinton said.

“The biggest problem we have is convincing people they ought to test their houses,” Quinton said. “Radon is naturally occurring and there is no one to sue. That means you are personally responsible.”

Relative Radon Concentrations

Zip codes where 14% of homes have elevated radon levels:

91301 (Agoura Hills) and 91302 (Calabasas).

Zip codes where 8% of homes have elevated radon levels:

93015 (Fillmore), 93065 & 93063 (Simi Valley) and 91361 (Thousand Oaks).

Zip codes where 1-2% of homes have elevated radon levels:

93001, 93003, 93004 (Ventura), 93010 (Camarillo), 91351 (Lake Sherwood), 93021 (Moorpark), 91320 (Newbury Park), 93022 (Oak View), 93023 (Ojai), 93035 (Oxnard), 93040 (Piru), 93041 (Port Hueneme), 93060 (Santa Paula), 93065 (Simi Valley) and 91360 (Thousand Oaks).

Source of Radon Test Kits

American Radon

Detection Co.

Thousand Oaks

523-1226

Radon Detection Systems

Saticoy

1-800-678-8879 or

659-2622

Chempet Research

Moorpark

529-0814

Source: Ventura County Health Department