What about radon in the West? - includes related article

What about radon in the West? Indoor pollution by radon is not a remote threat, nor is it a completely new one. But it's much in the news nowadays. A three-year study, released in January by the National Academy of Sciences Research Council, corroborates previous estimates that radon ranks second only to cigarette smoke as the country's leading cause of lung cancer.

Using data compiled by the research council, it can be calculated that 13,000 of the 152,000 people the American Cancer Society predicts will die of lung cancer in 1988 will do so as a result of exposure to radon.

Here we describe why and how this earth-produced radioactive gas permeates certain houses, how you can test for for it, and what you should do if you find dangerous concentrations in your house.

What is radon?

Radon is here to stay: it has been around since time began. Produced as uranium and radium--elements present in rocks and soils throughout the world--break down, radon percolates up through the soil. Escaping into the open air, the radioactive gas dilutes to become relatively harmless.

However, when it collects in an enclosed space--such as your house--it can be lethal. As radon decays, it emits alpha radiation, solid particles that can lodge in your lungs. According to the EPA, as many as 8 million houses in the U.S. may harbor hazardous levels.

Scientists have long know that radon poses a threat to the health of miners who work in poorly vented underground mines. Concern about indoor radon arose nearly 20 years ago, when unsafe levels were linked to radioactive fill dirt and building materials. In 1984 researchers found that naturally occurring radon is a much more pervasive threat to homeowners than had previously been thought.

Two years later, the EPA established 4 picocuries of radon per liter of air (pCi/l) as the "recommended action level." A picocurie is one-trillionth of a curie, a standard measure of radiation. Nationwide, the EPA estimates that 8 to 12 percent of all single-family detached houses may have radon concentrations that exceed 4 pCi/l. The agency has found elevated indoor radon concentrations in virtually every state, with particularly high levels in the Rocky Mountains, eastern Pennsylvania, and Florida.

In California, statewide study underway

In January the California Indoor Air Quality Program in the Department of Health Services joined with the Air Resources Board to launch a statewide study of radon. The study will measure levels in a random sample of 360 single-family homes--approximately one detached house for every five zip codes.

Project director Steve Hayward hopes to arrive at a better understadning of how geology, soil permeability, house type, operation patterns, and meteorological factors interact. Look for survey results in the fall of 1989.

Every house should be tested

Because you cannot see, taste, or smell radon, the only sure way to tell whether your home has a high level is to test. Fortunately, do-it-yourself test kits are inexpensive, reliable, and easy to use.

Testing is most imperative in areas where radon source strength is known to be high. As you see in the reproduction of the EPA's map (above left), ambient radon levels are highest in the intermountain states, and next highest in the desert states and mountainous regions of the coastal states. At sea leval in coastal states, high levels and infrequent but have been found.

To get a current appraisal of radon levels in your area, call your state health department or EPA office. These offices can also tell you about voluntary test programs and send you lists of reputable companies engaged in radon testing and mitigation work.

Radon concentrations can very from hour to hour, day to day, and season to season, but they tend to peak in winter. March is a good time to test: you're likely to obtain a "worst case" reading this month.

Mail-order test kits

Charcoal test kits ($10 to $25) give a screening measurement that will indicate if you have a problem, and whether additional measurements should be made. Recommended test periods usually range from two to four days. Typical procedures call for placing a testing device in a protected place, away from drafts, moisture (living rooms and bedrooms yield more reliable results than bathrooms and kitchens), and heating and cooling sources. When the test period is over, return the kit to the manufacturer for analysis.

If kit tests show between 4 and 20 pCi/l, the EPA suggests a longer-term, more sophisticated test using alpha-track detectors before undertaking any major corrective efforts. Leave detectors in two areas of your house for a month to a year. These detectors range from $20 to $50.

If you discover radon levels above 20 pCi/l, you should call in a professional to do detailed testing, pinpoint radon sources, and recommend appropriate reduction strategies. Expect to pay $250 to $300 for this service.

Radon testing has become a growth industry. To protect the public, the EPA conducts a radon measurement proficiency program. Companies and laboratories engaged in measuring indoor radon can participate on a voluntary basis. For a current list of qualified companies, call your regiona EPA office.