ASBESTOS PANIC

Asbestos was one of the common building materials in the USA until the late 1970s, when large numbers of industrial workers who used it developed cancer. A small fiber mined on six continents, asbestos is prized for its ability to add strength and heat resistance to a variety of materials. At its peak in 1973, the United States used 795,000 metric tons of asbestos in roofs, floors, insulation and hundreds of other products. (A metric ton is 2,200 pounds.)

The crusade to remove asbestos results from a failure to make a distinction about when asbestos is dangerous. Asbestos dust has caused tragic rates of cancer in miners and workers who made and installed asbestos products with insufficient precautions. The workers inhaled asbestos fibers, often for years of decades.

But "once products with asbestos are installed, so few fibers are released that the air inside even the most asbestos-rich building is indistinguishable from the air outdoors."

Why have Americans spent billions attacking a minor health risk?

The experts say the fear created by the health tragedy that befell asbestos workers - and the multibillion -dollar lawsuits that followed-overwhelmed the scientific evidence.

In the past 30 years, 171,500 workers in the United States have died of asbestos -related cancers, the worst occupational health disaster of the century. An additional 119,000 U.S. deaths are expected before the epidemic winds down in 2025. Unsafe use of asbestos in poorer nations will cause 30,000 cancer deaths per year for the foreseeable future.

In the 1970s and 1980s in court, plaintiffs' lawyers proved companies hid the dangers of asbestos long after they were known.

So far, 40,000 lawsuits have been resolved; Y 2000,000 are pending. The lawsuits forced Johns-Manville Corp., a powerful building materials company, to seek bankruptcy protection in 1982 and turn over 80% of its stock to workers exposed to asbestos.

Linda Rosen stock, director of the National Institute for Occupational Health and Safety, researched the dangers of asbestos early in her career and remains extremely concerned about its unsafe use. But she says even people who should know better lack a sense of proportion about asbestos risks.

"I remember getting panicked calls from other doctors who had been exposed to a burst of asbestos dust while working on a boiler or whatever," she says. "I would tell them, 'Calm down. It's no worse than smoking a couple of cigarettes.' Those two cigarettes are certainly not good for your health, but you have to keep it in perspective. The dangers of asbestos - like smoking - depend on amount and duration of exposure."

Workers who developed asbestos -related disease often spent years in clouds of asbestos dust, spraying insulation inside ships or weaving fireproof cloth at textile mills. They worked in places that might have a typical asbestos dust level of 10 fibers per cubic centimeter of air --- enough to cause 20% of workers exposed for 20 years to develop lung cancer or mesothelioma, a fatal cancer of the lung's lining. Their exposure was so high that their spouses had the elevated cancer rates because of dust carried home on clothing.

But the risk of U.S workers from asbestos has been reduced dramatically by relatively inexpensive safety techniques, such as improving ventilation, wetting the dust with water and using respirators. The legal limit on asbestos exposure for workers is 0.1 fibers per cubic centimeter of air, and compliance has not been a problem.

The United States used 21,700 metric tons of asbestos in 1996, mostly in water pipes, brake linings and roof coatings. Consumption is expected to continue at that level.

In everyday life, breathing asbestos is unavoidable. Asbestos is a natural mineral released into the air by wind and erosion, as well as from man-made sources such as brake linings.

Once asbestos is installed, it rarely causes problems to a building's users. Only in a few instances - such as janitor's removal of asbestos insulation - will a worker be exposed to a high level of asbestos for a short time.

Yet asbestos removal continues on a large scale when there is concrete proof of no danger.

The renovation of a post office in Fort Myers, Fla., last year is typical. The old floor was found to contain asbestos. Testing found no asbestos fibers in the post office's air and only a few fibers in the air-conditioning filter. But the post office did what is now a common and costly practice.

It halted construction and hired a special crew of men dressed in spacesuits to remove the floor. Customers were banned from the building. A counter was set up outdoors to sell stamps and hand out mail. The cleanup added $ 255,000 to the original renovation cost of $470,000.