The "no threshold" dogma for cancer induction that is being foisted on the American public is generating a national crisis that is seriously damaging our economy.

The economic consequence of such a cancer prevention policy is particularly apparent on examining the asbestos abatement program for schools and other buildings. Asbestos removal has cost this nation 50 to 100 billion dollars, has depreciated commercial building by one trillion dollars, and has increased, not decreased risk of injury or death, both from increased exposure to asbestos dusts during the dirty ripouts and from job accidents by the abatement workers.

That asbestos causes cancer among heavily exposed workers, coupled with the hypothesis that there is no known threshold for the induction of a tumor by a carcinogenic substance, justified this extraordinarily expensive abatement program—a program that is abetted by the false concept that a schoolchild's exposure to asbestos fiber, even in minute quantities, could later cause that child to develop cancer. Unfortunately, asbestos removal continues; approximately $3.1 billion was spent for this nefarious activity in 1993.

U.S. Environmental Protection Agency first promoted the removal of asbestos in schools, homes, and commercial buildings through six advisory documents published in the 1980's. However, in July of 1990 the EPA published a new advisory document titled "Managing Asbestos in Place." Among the statements presented in this 1990 advisory are: (1) asbestos hazard is dependent on dose, therefore low-dose means low-risk; (2) on the basis of available data, the fiber levels in buildings are low; accordingly, health risk to occupants also appears to be low; and (3) removal is often not the best course of action. "In fact", the text states, "an improper removal can create a dangerous situation where none previously existed."

Despite this advice by the EPA, the removal of asbestos from schools and other buildings continues. For example, in August and September of 1993 the New York City school system spent nearly $100 million for asbestos removal. During this time many schools remained closed and parents were subjected to a massive media coverage that promoted the idea that the schoolchildren might develop asbestos-related cancer sometime in the future. At no time did an EPA official publicly inform New York City school administrators of the 1990 EPA advisory. The fear of asbestos in the New York City schoolrooms was completely unjustified.

A recent review document by the Health Effects Institute summarized the asbestos air concentrations measured in United States and Canadian schools that contained asbestos. It was found that the average concentration in these schools was two ten thousandths of an asbestos fiber per cubic centimeter. The calculated risk to the children from a 12 school-year exposure to this concentration of asbestos, using the most pessimistic risk model, is one excess cancer death per one million lifetimes; the risk of dying from a lightning bolt is 35 times greater. The air sampling data collected in schools do not support the concept that low-level exposure to asbestos is a significant risk. As stated by Dr. Brooke Mossman at the University of Vermont College of Medicine and her coworkers "clearly the asbestos panic in the U.S. must be curtailed, especially because unwarranted and poorly controlled abatement results in unnecessary risks to young removal workers."

Few people realize that the current Federal regulatory structure is based in large part on a health policy that demands that we live and work in a risk-free environment. The prevailing cancer dogma in the United States espouses the "no threshold" theory of cancer induction. It is stated repeatedly by certain influential health specialists that, since no one knows the minimum amount of a carcinogen required to initiate the growth of a tumor, it must be assumed that any amount of a carcinogen is unsafe. Thus, the public is led to believe that exposure to just one molecule of a chemical carcinogen can cause cancer. Regarding exposure to asbestos and other mineral dusts, this paradigm becomes "one mineral fiber or particle can kill." What the public has not been told is that simply living on Earth exposes us to innumerable naturally occurring carcinogens. From many previous studies, we can predict that at least one-half of all chemicals, whether natural or man-made, when tested in animals at very high doses will produce tumors; when applied in low doses few if any tumors are produced. These high doses cause extensive tissue cell destruction and subsequent cell replacement; these processes greatly increasing the chances of chromosome damage with a concomitant increase cancer risk.

Common sense must prevail concerning the regulation of carcinogens, otherwise many thousands of substances will be designated as possibly carcinogenic to humans, including play-box sand. The "no threshold" hypothesis of cancer induction must be abandoned and other criteria used to control substances that may cause disease. To prevent occupationally induced cancer, the object of regulatory control should be to prevent chronic tissue damage, where thresholds can be defined. In conclusion, we should recall the centuries-old admonition of Paracelsus (1493-1541): "Everything is a poison, nothing is a poison, the dose alone makes the poison."

Malcolm Ross, Ph.D., is associated with the Science and Environmental Policy Project, Fairfax, Virginia. He has 41 years experience as a research scientist with the U.S. Geological Survey, publishing 25 articles on the health effects of mineral dusts and co-authoring the book Asbestos and Other Fibrous Materials.