ALAS, AQUARIUS

By CLEM LAY, Public Works Coordinator, Michigan Municipal League

By the 1950s, analytical chemists were able to detect and measure a few materials at levels approaching 1 part per million. We began to be aware of traces of materials in our environment that we had given little thought to previously.

We have since increased our capabilities to detecting and measuring parts per billion and, in some instances, parts per trillion. Our growing awareness has been matched by fears over what these trace materials might be doing to the environment, and to us.

One early consequence of this awareness was the publicizing, in the late 50s, of the presence of a weed control chemical (aminotriazole) in cranberries, that in large doses caused cancer in some lab animals. This report generated fears which effectively wiped out the cranberry industry for several years. Too late, a few scientists concluded that a person would have to eat a boxcar full of cranberries to get a toxic dose of aminotriazole — even assuming that the animal data applied to humans.

Using lab animals to estimate the effect of materials in humans has been the basis of our predictive toxicology for decades now. Most of us have overlooked the questions of many scientists about the validity of this approach.

One classic example where the application of animal testing to humans fell down completely is the case of thalidomide.

In the late 1950's, this drug, a mild tranquilizer, was widely prescribed for pregnant women in Europe. Extensive testing on lab animals demonstrated no significant toxicity and no detectable side effects — including birth defects. Manufacturers requested permission to market the drug in the U.S. During the Food and Drug Administration review process, one FDA scientist noted the casual remark in a lab notebook that the lab animals, in contrast to humans, were not tranquilized by the drug. She reasoned that, if the drug had opposite effects in humans and animals in one parameter, it might have opposite effects in others. On this basis alone she recommended denial, pending further study.

The bottom line? Extensive birth defects in Europe; children were born with deformed legs, arms, heads and other abnormalities. Such widespread defects were avoided in this country because one scientist picked up on the possibility that this material might have exactly opposite effects in humans and animals.

In most cases, lab animal data is probably predictive of basic toxicity. More and more scientists are concerned about the custom of giving animals very large doses of chemicals and attempting to predict cancer probability in humans from very low doses. If respected scientists still debate the issue, how do we lay people put the matter into perspective?

Most reputable scientists assess risk in a variety of ways, and are working to introduce a common sense perspective into dealing with the risks in our everyday lives — risks we take without second thought.

Until the late 70s, an animal study could cost up to $500,000 per chemical. As a result, only several hundred chemicals world-wide had been tested. These were exclusively man-made chemicals. Since then, very inexpensive and rapid tests for carcinogenicity have been developed.

With such a "toy", scientists such as Dr. Bruce Ames, University of California, are discovering that we live in a world full of carcinogens.¹ Most of these carcinogens are naturally occurring and, almost without exception, far more potent than the few man-made chemicals that have generated so much concern over the past 30 years.

Ames and other scientists are finding natural carcinogens in peanut butter, mushrooms, cola drinks, bread, beer, wine, mustard and other spices, celery and other vegetables, etc., etc., etc. The chemistry of cooking, especially grilling, produces natural carinogens. So too does the baking of bread. Untold tons of natural carcinogens are dumped on the ground when plants die and decay. Human metabolism produces carcinogens, and these circulate in our blood until excreted or neutralized in various ways.

Let's compare the relative risk of some of these

February 1990 / Illinois Municipal Review / Page 9

everyday carcinogens to the EPA limit for chlorinated organics in drinking water:

• Eating one serving of peanut butter daily is 30 times as hazardous due to aflatoxin in the peanut butter. It also occurs in corn, wheat and other grains.

• Breathing the air in your home is 600 times as hazardous due to formaldehyde formed naturally. Formaldehyde is produced naturally in human bodies and occurs naturally in a large number of foods and beverages.

• One 12 oz. beer daily is 3000 times as hazardous. (Alcohol is a carcinogen).

• A diet cola daily is 60 times the risk (saccharin).

• One average mushroom daily poses 100 times the risk because of the various natural hydrazines.

• Four strips of bacon daily is 3 times as hazardous (various nitrosamines).

• The amount of mustard you typically put on one hot dog, if eaten daily, is 70 times as hazardous (allyl isothiocyanate).

The list of examples grows daily. Why are we still living? Because of the many natural mechanisms in our bodies, which are only now being understood, that defend us against this world full of carcinogens. Ain't nature wonderful!

Regulatory agencies generally aim to hold the risk limit for exposure to chemicals at one in a million. That is, no more than one additional cancer per million people will be accepted. Achieving this can be extremely costly. Is there a proper perspective here?

Consider that the overall rate for cancer from all causes is one in four, and the great majority of these come from easily controllable causes. Smoking alone is estimated to account for one-third of all the cancers in our population. Dietary habits, drinking and other life style factors raise this total to over two-thirds. If these personally controllable causes have a risk of about 175,000 cancers in one million, why the hysteria over a theoretically possible one more? We are quibbling over the difference between 175,000 and 175,001.

Information from the American Cancer Society shows that over the past half century, the 10 most common forms of cancer have, with two exceptions, remained at a fixed level in our population. Lung cancer has risen dramatically (for obvious reasons), and stomach cancer has decreased significantly (attributed to improved dietary habits).

The levels of most cancers have remained constant, even though the types and quantities of man-made chemicals produced and used by society had increased dramatically. It would appear that those who generate the fears are wrong, and they are arousing fears out of all proportion to reality.

The Age of Aquarius was to have lasted a thousand years. Alas, it seems to have given way to the Age of Paranoia.

In summary, we can now detect extremely small quantities of materials in our environment. Relating the effects of these materials in animals to humans is debatable. We have done so anyway. What we have not done is put these extrapolations into some sense of perspective.

Local officials coping with tight budgets, limited revenues and hard decisions over priorities cannot afford to be frightened into spending big dollars on perceived problems that may, in fact, be little more than emotional over-reaction to bad information. They must try to make sure the problems are real. This can be difficult. Asking questions, seeking advice from people who are technically competent in risk assessment and applying your own common sense will help sort the wheat from the chaff. •

Reprinted with permission from the Michigan Municipal Review.

Page 10 / Illinois Municipal Review / February 1990