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Mercury pollution threat to global environment

Mercury-laden swordfish and "tainted tuna" were recently banned for sale as human food.
Which species will be next?
Is the "mercury scare" merely a passing concern,
or does it point up a basic fault in our modern technology?


LAST YEAR Americans dumped over 1.2 million pounds of mercury into the air and water. Scientists now tell us this was a grave mistake. Mercury, once thought to be inert in the ecosystem, has proven deadly — and even if we quit dumping it now, mercury already in our atmosphere and waterways will still be there for decades to come.


The "Old Problem" of Mercury

Even before modern scares from mercury poisoning, "Alice in Wonderland's" Mad Hatter characterized a very real tragedy experienced by workers in European hat factories in the 1800's.

One step involved the use of mercury to shrink the fibers. Over a period of time, workers in these factories breathed enough mercury vapors to contract mercurial poisoning. Symptoms included headaches, weakness, emotional upset, tremors, respiratory failure, brain damage and eventually death.

These cases of poisoning were tragic, yet relatively few in relation to the modern mercury scare. Today the stakes are much higher — not just a few workers in a hat factory, but our entire global environment is threatened by mercury pollution.


Modern Mad Hatters

Modern "Mad Hatter" incidents have turned up with tragic results in recent decades. Yet human beings — industry, governments, farmers and others — have been slow to heed the handwriting on the wall.

In 1953, local Japanese fishermen living in Minamata Bay died from mercury poisoning. Cause — a plastics factory located near the bay used mercury in its manufacturing process, and dumped the mercury-laden effluent into the bay. Effect — when local fishermen and their families ate fish caught in Minamata Bay, a disastrous toll of scores of human lives was taken.

In the case of Minamata Bay, the plastics factory eliminated most of its mercury discharge, and the local people quit eating contaminated fish from Minamata Bay. The case was closed — as far as the public was concerned.

Reports of such incidents were publicized. Yet few regarded them of important concern. Isolated cases of massive mercurial poisoning were just that — isolated cases — or so it was thought. It was assumed there was no cause for alarm about any widespread mercury poisoning. Low levels of mercury in the human body had never been proved harmful. Of course, neither had low levels been proved harmless. Studies just had not been made.

Now, after cataloging symptoms of mercury poisoned individuals, some doctors have a hunch that wards of mental hospitals and cases of premature senility might be fruitful fields for investigation. The symptoms exhibited among these people are the SAME as those exhibited in cases of known mercury poisoning.


Behind the Scenes

Few were aware that mercurial discharge into the environment had already been going on for decades — and, as a result of new technologies, in huge quantities. Little did anyone realize how dangerous mercury dumping would prove later.

In preparing this article, we talked with scientists who are gravely concerned about the global ecosystem. We wondered if the news media was overemphasizing — sensationalizing — this recent mercury scare. We wondered if the major news sources were blowing up this problem out of proportion to other pollution problems.

One scientist working directly on the mercury pollution problem summarized his and some of his colleagues' thoughts by saying, "The threat of mercury pollution — and other heavy metals such as cadmium, lead, zinc, beryllium, vanadium and others — is so great scientists themselves don't even know the long-lasting effects. This problem can't be blown up too big. Its effects are global!"

You may wonder how mercury pollution can be of such global significance, when so few products we normally use contain mercury. Namely, thermometers, "sun" lamps for indoor sunbathers, and certain batteries for small radios. Surely these few products alone cannot be the source of such massive spread of mercury into the environment. They are not!


Mercury in Industry

By far the largest user of mercury is industry. Some 26% of the 78,000 flasks of mercury and mercury compounds used in the United States annually are "consumed" by the chlorine and caustic soda (lye) industry. Actually, the mercury used is a catalyst and not a product itself. During the electrolytic process of converting brine (salt water) into chlorine and lye, mercury is used as an electrical conductor, which combines with sodium from the salt solution. Later the sodium-mercury "amalgam" is separated, with the addition of water, thus forming lye and freeing the mercury for reuse.

In theory, no mercury is used up. In actual practice, however, small amounts of mercury are lost throughout this process, by vaporization, leakage and accidental spills. We suffer from the basic technological inability to eliminate the loss of mercury at a low cost. For every ton of chlorine gas produced, a half pound of mercury is "lost" into the environment. “Lost" is a poor choice of words, however, since one of the most fundamental laws of ecology is that "everything has to go somewhere."

Total United States mercury production is some 6,000,000 pounds each year, and about one fifth of this escapes into the environment in the form of waste discharge. Until recent government crackdowns, some individual chlorine-lye plants were losing 200 pounds of mercury into nearby waterways every operating day. Coal-burning power plants in the United States alone may be putting up to 150 tons of mercury vapor into the skies every year. Rains and wind deposit this back to the earth in the form of pollutants.

Considering the high toxicity of mercury, just half a jigger of a mercury compound dissolved in a tank car of water would make a concentration of poison about equal to the toxic limit of mercury allowed in food (.5 parts per million) set by the Food and Drug Administration. (Half a pound of mercury is able to contaminate 10 million pounds of fish, according to the more stringent World Health Organization standards of .05 ppm)

Scientists have estimated that the total amount of mercury released into the environment during the years from 1945 to 1958 was 24 million pounds, almost half of the 50 million pounds produced during those years. Since 1900, the United States has produced and used some 160 million pounds. When released into the environment every ounce of this remains potentially poisonous, when converted to methyl-mercury by microorganisms.

Some of the other means whereby mercury has escaped into the environment are from discarded electrical equipment — certain batteries for transistor radios, electrical switches, mercury vapor lamps. These and a host of other electrical gadgets are responsible for 24% of the total mercury use. Other uses are anti-fouling and fungus-resistant paints for ship bottoms and houses (12%). The remaining 38% of mercury is used in slime inhibitors used in manufacture of paper, fillings for dentistry, catalysts, agricultural fungicides and pesticides and other products.


"Unknown Killer"

But if all this mercury were being proliferated in new industrial processes and in products, why didn't the manufacturers warn an unknowing public about the dangers?

The answer is simple.

No one really knew the end results. No one knew what would happen to the mercury once it entered the natural systems of earth.

After all, mercury has been around for millennia in the form of cinnabar and other compounds — from which mercury is mined. Mercury found naturally in rocks is constantly being released, flowing naturally throughout the earth's systems. In fact, mercury is found naturally in living animals, and in humans.

Bones of ancient Peruvian Indians were tested for mercury content, and found to contain much lower levels than "average" humans do today, pointing to the increased proliferation of mercury in modern times.

Danger emerges, however, when man takes huge quantities of a substance — in this case, mercury — and concentrates it in a specific area by allowing its discharge into the natural ecosystem. Here an unnatural imbalance of the substance becomes highly poisonous to life forms.

For example, below one chemical plant which discharged mercury wastes into the Great Lakes region, concentrations of mercury 560 parts per million were found in mud 125 feet downstream from the discharge point. Four miles downstream concentrations of 50 ppm were found. This is true, even though the company had kept its waste stream mercury content to .1 ppm — well under the .5 ppm toxic limit set by the FDA for food.

"We knew we were losing mercury," the company admitted, "but we just didn't think the concentration was high enough to be harmful." (How mercury is changed into methyl-mercury, and made very harmful, is explained later)

This belated admission points up a fundamental flaw in the present technological process. Products are manufactured and used without a thorough understanding of their effect on our environment. One of the hidden costs is that of getting rid of "wastes" from the manufacturing process — "wastes" being in reality by-products for which the manufacturers perhaps could, but often do not, find a use. The effect and ultimate costs of these wastes in many cases is much greater than the direct cost of the product itself. These "hidden" costs must be paid later, and are now proving disastrously expensive.


A Case in Point

In Lake St. Clair, on the United States-Canadian border in the Great Lakes region the mercury from industrial wastes has wrecked sport and commercial fishing, and endangered human health.

Noted biologist Barry Commoner of Washington University in St. Louis divulged some statistics at the American Association for the Advancement of Science (AAAS) meeting held in Chicago, December, 1970. Dr. Commoner estimated that in recent years about 100,000 pounds of mercury was released into Lake St. Clair annually. At $5.50 per pound, the current market price for mercury, the average yearly cost of "lost" mercury annually dumped into Lake St. Clair would be some $550,000. Yet, due to the contamination effects of this mercury on fish, Lake St. Clair's commercial fishing operation valued at $500,000,000 annually was closed!

The cost to commercial fishing comes to nearly $5000 for every pound of mercury released each year by the chemical industry! In addition, tourism, sport fishing, and even land values were all affected to a great extent.

Carrying this calculation one step further, the value of goods produced by the industries which released mercury into Lake St. Clair is estimated at some $40 to $50 million annually, or only about one tenth of the annual value of the commercial fishing operation which had to be closed down.

Truly, a high price to pay, and hardly an equitable compensation for the release of mercury into the environment.

Cases such as this cause serious concern over the uncontrolled technology of highly industrialized societies.