State to Test Radon Levels in Ventura, L.A. Counties

State health officials this month will mail letters to about 5,000 residents of Ventura and Los Angeles counties asking them to participate in a study to determine the extent of radon, a radioactive gas that can cause lung cancer.

A total of 1,000 households will be chosen for the survey, which will encompass Ventura County and adjoining areas of Los Angeles County, including Agoura, Pacific Palisades, Westwood, Hollywood and much of the San Fernando Valley.

Kenneth W. Kizer, director of the state Department of Health Services, ordered the study in October after learning the results of a yearlong survey by The Times.

The Times study found that the chances of exceeding recommended radon limits were higher than the Southern California average in a fast-growing southeastern Ventura County area that includes Simi Valley, Thousand Oaks and Moorpark. While Kizer called the Ventura County results only “mildly elevated” and relatively low in comparison to other U.S. areas, he ordered a more comprehensive study.

Survey Delayed

The $40,000 survey was to begin last fall but was delayed because of difficulties in finding funding, said Steven Hayward, manager of the state Department of Health Services’ Indoor Air Quality Program. Funds were trimmed from other department programs to pay for the study, he said.

About 800 homes in Ventura County will begin the yearlong test in June, Hayward said, along with 200 homes in adjoining areas in Los Angeles County.

Hayward said residents’ names were randomly chosen from property tax rolls in Ventura County and from Department of Motor Vehicles records in Los Angeles County. State health officials will choose a geographically representative sample of 1,000 homes from the responses they receive and mail testing devices to residents to install, he said.

“The more people that respond, the better our sample will be,” Hayward said. “But people shouldn’t just call in to volunteer because we’re only using homes that have been randomly chosen.”

Letters to be mailed to the 5,000 residents will include a two-page fact sheet on radon and a postage-paid response.

3-Month Study

About 200 of the 1,000 homes will receive a second device that will monitor radon levels for three months. This will give state health officials an early sense of the geographic distribution of any high radon levels, Hayward said.

But the longer testing period of a year is necessary because radon levels fluctuate seasonally, with higher levels often found in the winter when homes tend to be kept sealed from the cold, he said.

The state’s survey comes at a time of growing national concern about the health threat posed by radon. Radon, which is produced by the natural decay of uranium, is the second leading cause of lung cancer in the United States.

In September, the U.S. Environmental Protection Agency joined the Surgeon General in issuing an unprecedented national health advisory urging virtually all homeowners nationwide to test their homes for the gas, which is found in soils throughout the world. Kizer pointed out that state testing is under way and said that it is too early for his department to recommend that everyone test.

Because of slight differences in air pressure inside the house and outdoors, radon gas can be drawn into the house much like smoke is drawn up a fireplace chimney. The gas enters the house through cracks in concrete slab foundations, openings around plumbing and elsewhere.

Locations Confidential

The exact location of the 1,000 homes and the identity of residents will be confidential, Hayward said. But California law requires home sellers to disclose to potential buyers anything they know that affects the habitability or marketability of the property. However, Hayward said, homes with radon readings above the EPA’s recommended limit of 4 picocuries per liter of air could be modified for “a few hundred to a couple of thousand dollars” to reduce the gas to safe levels.

Early in the study, health officials from Los Angeles and Ventura counties will visit the homes to make sure that the devices are installed properly, Hayward said. The detectors are supposed to be placed in a heavily used room on the ground floor or the lowest occupied floor, he said. Participants will be asked to mail back the devices at the end of the study, he said.

The survey will involve three times as many homes as the state is already monitoring for radon throughout California. The current survey of 360 homes is being conducted by the Department of Health Services and the state Air Resources Board.

In its study last year, The Times tested 436 residences in a Southern California region that includes Los Angeles and Orange counties and parts of Riverside, San Bernardino and Ventura counties.

RADON TESTING AREAS

* Ventura Co.: 800 homes selected from throughout the entire county.

* Los Angeles Co.: 200 homes selected from within the communities of Agoura Hills, Bel-Air, Beverly Hills, Brentwood, Canoga Park, Chatsworth, Encino, Hollywood, Mission Hills, Newhall, Pacific Palisades, Saugus, Sherman Oaks, Tarzana, Topanga, Valencia, Westwood and Woodland Hills.