POLLUTION

AIR POLLUTION

Air Pollution, addition of harmful substances to the atmosphere resulting in damage to the environment, human health, and quality of life. One of many forms of pollution, air pollution occurs inside homes, schools, and offices; in cities; across continents; and even globally. Air pollution makes people sick—it causes breathing problems and promotes cancer—and it harms plants, animals, and the ecosystems in which they live. Some air pollutants return to Earth in the form of acid rain and snow, which corrode statues and buildings, damage crops and forests, and make lakes and streams unsuitable for fish and other plant and animal life.

Pollution is changing Earth’s atmosphere so that it lets in more harmful radiation from the Sun. At the same time, our polluted atmosphere is becoming a better insulator, preventing heat from escaping back into space and leading to a rise in global average temperatures. Scientists predict that the temperature increase, referred to as global warming, will affect world food supply, alter sea level, make weather more extreme, and increase the spread of tropical diseases.

MAJOR POLLUTANT SOURCES

Most air pollution comes from one human activity: burning fossil fuels—natural gas, coal, and oil—to power industrial processes and motor vehicles. Among the harmful chemical compounds this burning puts into the atmosphere are carbon dioxide, carbon monoxide, nitrogen oxides, sulfur dioxide, and tiny solid particles—including lead from gasoline additives—called particulates. Between 1900 and 1970, motor vehicle use rapidly expanded, and emissions of nitrogen oxides, some of the most damaging pollutants in vehicle exhaust, increased 690 percent. When fuels are incompletely burned, various chemicals called volatile organic chemicals (VOCs) also enter the air. Pollutants also come from other sources. For instance, decomposing garbage in landfills and solid waste disposal sites emits methane gas, and many household products give off VOCs.

Some of these pollutants also come from natural sources. For example, forest fires emit particulates and VOCs into the atmosphere. Ultrafine dust particles, dislodged by soil erosion when water and weather loosen layers of soil, increase airborne particulate levels. Volcanoes spew out sulfur dioxide and large amounts of pulverized lava rock known as volcanic ash. A big volcanic eruption can darken the sky over a wide region and affect the Earth’s entire atmosphere. The 1991 eruption of Mount Pinatubo in the Philippines, for example, dumped enough volcanic ash into the upper atmosphere to lower global temperatures for the next two years. Unlike pollutants from human activity, however, naturally occurring pollutants tend to remain in the atmosphere for a short time and do not lead to permanent atmospheric change.

Once in the atmosphere, pollutants often undergo chemical reactions that produce additional harmful compounds. Air pollution is subject to weather patterns that can trap it in valleys or blow it across the globe to damage pristine environments far from the original sources.

Local and regional pollution take place in the lowest layer of the atmosphere, the troposphere, which at its widest extends from Earth's surface to about 16 km (about 10 mi). The troposphere is the region in which most weather occurs. If the load of pollutants added to the troposphere were equally distributed, the pollutants would be spread over vast areas and the air pollution might almost escape our notice. Pollution sources tend to be concentrated, however, especially in cities. In the weather phenomenon known as thermal inversion, a layer of cooler air is trapped near the ground by a layer of warmer air above. When this occurs, normal air mixing almost ceases and pollutants are trapped in the lower layer. Local topography, or the shape of the land, can worsen this effect—an area ringed by mountains, for example, can become a pollution trap.

Smog and Acid Precipitation

Smog is intense local pollution usually trapped by a thermal inversion. Before the age of the automobile, most smog came from burning coal. In 19th-century London, smog was so severe that street lights were turned on by noon because soot and smog darkened the midday sky. Burning gasoline in motor vehicles is the main source of smog in most regions today. Powered by sunlight, oxides of nitrogen and volatile organic compounds react in the atmosphere to produce photochemical smog. Smog contains ozone, a form of oxygen gas made up of molecules with three oxygen atoms rather than the normal two. Ozone in the lower atmosphere is a poison—it damages vegetation, kills trees, irritates lung tissues, and attacks rubber. Environmental officials measure ozone to determine the severity of smog. When the ozone level is high, other pollutants, including carbon monoxide, are usually present at high levels as well.

In the presence of atmospheric moisture, sulfur dioxide and oxides of nitrogen turn into droplets of pure acid floating in smog. These airborne acids are bad for the lungs and attack anything made of limestone, marble, or metal. In cities around the world, smog acids are eroding precious artifacts, including the Parthenon temple in Athens, Greece, and the Taj Mahal in Āgra, India. Oxides of nitrogen and sulfur dioxide pollute places far from the points where they are released into the air. Carried by winds in the troposphere, they can reach distant regions where they descend in acid form, usually as rain or snow. Such acid precipitation can burn the leaves of plants and make lakes too acidic to support fish and other living things. Because of acidification, sensitive species such as the popular brook trout can no longer survive in many lakes and streams in the eastern United States.

Smog spoils views and makes outdoor activity unpleasant. For the very young, the very old, and people who suffer from asthma or heart disease, the effects of smog are even worse: It may cause headaches or dizziness and can cause breathing difficulties. In extreme cases, smog can lead to mass illness and death, mainly from carbon monoxide poisoning. In 1948 in the steel-mill town of Donora, Pennsylvania, intense local smog killed 19 people. In 1952 in London about 4,000 people died in one of the notorious smog events known as London Fogs; in 1962 another 700 Londoners died.

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With stronger pollution controls and less reliance on coal for heat, today’s chronic smog is rarely so obviously deadly. However, under adverse weather conditions, accidental releases of toxic substances can be equally disastrous. The worst such accident occurred in 1984 in Bhopāl, India, when methyl isocyanate released from an American-owned factory during a thermal inversion caused more than 3,800 deaths.

GLOBAL SCALE POLLUTION

Air pollution can expand beyond a regional area to cause global effects. The stratosphere is the layer of the atmosphere between 16 km (10 mi) and 50 km (30 mi) above sea level. It is rich in ozone, the same molecule that acts as a pollutant when found at lower levels of the atmosphere in urban smog. Up at the stratospheric level, however, ozone forms a protective layer that serves a vital function: It absorbs the wavelength of solar radiation known as ultraviolet-B (UV-B). UV-B damages deoxyribonucleic acid (DNA), the genetic molecule found in every living cell, increasing the risk of such problems as cancer in humans. Because of its protective function, the ozone layer is essential to life on Earth.

 Ozone Depletion

Several pollutants attack the ozone layer. Chief among them is the class of chemicals known as chlorofluorocarbons (CFCs), formerly used as refrigerants (notably in air conditioners), as agents in several manufacturing processes, and as propellants in spray cans. CFC molecules are virtually indestructible until they reach the stratosphere. Here, intense ultraviolet radiation breaks the CFC molecules apart, releasing the chlorine atoms they contain. These chlorine atoms begin reacting with ozone, breaking it down into ordinary oxygen molecules that do not absorb UV-B. The chlorine acts as a catalyst—that is, it takes part in several chemical reactions—yet at the end emerges unchanged and able to react again. A single chlorine atom can destroy up to 100,000 ozone molecules in the stratosphere. Other pollutants, including nitrous oxide from fertilizers and the pesticide methyl bromide, also attack atmospheric ozone.

Scientists are finding that under this assault the protective ozone layer in the stratosphere is thinning. In the Antarctic region, it vanishes almost entirely for a few weeks every year. Although CFC use has been greatly reduced in recent years and will soon be prohibited worldwide, CFC molecules already released into the lower atmosphere will be making their way to the stratosphere for decades, and further ozone loss is expected. As a result, experts anticipate an increase in skin cancers, more cataracts (clouding of the lens of the eye), and reduced yields of some food crops.

INDOOR AIR POLLUTION

Pollution is perhaps most harmful at an often unrecognized site—inside the homes and buildings where we spend most of our time. Indoor pollutants include tobacco smoke; radon, an invisible radioactive gas that enters homes from the ground in some regions; and chemicals released from synthetic carpets and furniture, pesticides, and household cleaners. When disturbed, asbestos, a nonflammable material once commonly used in insulation, sheds airborne fibers that can produce a lung disease called asbestosis.

Pollutants may accumulate to reach much higher levels than they do outside, where natural air currents disperse them. Indoor air levels of many pollutants may be 2 to 5 times, and occasionally more than 100 times, higher than outdoor levels. These levels of indoor air pollutants are especially harmful because people spend as much as 90 percent of their time living, working, and playing indoors. Inefficient or improperly vented heaters are particularly dangerous.

POLLUTION CLEANUP AND PREVENTION

In the United States, the serious effort against local and regional air pollution began with the Clean Air Act of 1970, which was amended in 1977 and 1990. This law requires that the air contain no more than specified levels of particulate matter, lead, carbon monoxide, sulfur dioxide, nitrogen oxides, volatile organic compounds, ozone, and various toxic substances. To avoid the mere shifting of pollution from dirty areas to clean ones, stricter standards apply where the air is comparatively clean. In national parks, for instance, the air is supposed to remain as clean as it was when the law was passed. The act sets deadlines by which standards must be met. The Environmental Protection Agency (EPA) is in charge of refining and enforcing these standards, but the day-to-day work of fighting pollution falls to the state governments and to local air pollution control districts. Some states, notably California, have imposed tougher air pollution standards of their own.

In an effort to enforce pollution standards, pollution control authorities measure both the amounts of pollutants present in the atmosphere and the amounts entering it from certain sources. The usual approach is to sample the open, or ambient, air and test it for the presence of specified pollutants. The amount of each pollutant is counted in parts per million or, in some cases, milligrams or micrograms per cubic meter. To learn how much pollution is coming from specific sources, measurements are also taken at industrial smokestacks and automobile tailpipes.

Pollution is controlled in two ways: with end-of-the-pipe devices that capture pollutants already created and by limiting the quantity of pollutants produced in the first place. End-of-the-pipe devices include catalytic converters in automobiles and various kinds of filters and scrubbers in industrial plants. In a catalytic converter, exhaust gases pass over small beads coated with metals that promote reactions changing harmful substances into less harmful ones. When end-of-the-pipe devices first began to be used, they dramatically reduced pollution at a relatively low cost. As air pollution standards become stricter, it becomes more and more expensive to further clean the air. In order to lower pollution overall, industrial polluters are sometimes allowed to make cooperative deals. For instance, a power company may fulfill its pollution control requirements by investing in pollution control at another plant or factory, where more effective pollution control can be accomplished at a lower cost.

End-of-the-pipe controls, however sophisticated, can only do so much. As pollution efforts evolve, keeping the air clean will depend much more on preventing pollution than on curing it. Gasoline, for instance, has been reformulated several times to achieve cleaner burning. Various manufacturing processes have been redesigned so that less waste is produced. Car manufacturers are experimenting with automobiles that run on electricity or on cleaner-burning fuels. Buildings are being designed to take advantage of sun in winter and shade and breezes in summer to reduce the need for artificial heating and cooling, which are usually powered by the burning of fossil fuels.

The choices people make in their daily lives can have a significant impact on the state of the air. Using public transportation instead of driving, for instance, reduces pollution by limiting the number of pollution-emitting automobiles on the road. During periods of particularly intense smog, pollution control authorities often urge people to avoid trips by car. To encourage transit use during bad-air periods, authorities in Paris, France, make bus and subway travel temporarily free.

Indoor pollution control must be accomplished building by building or even room by room. Proper ventilation mimics natural outdoor air currents, reducing levels of indoor air pollutants by continually circulating fresh air. After improving ventilation, the most effective single step is probably banning smoking in public rooms. Where asbestos has been used in insulation, it can be removed or sealed behind sheathes so that it won’t be shredded and get into the air. Sealing foundations and installing special pipes and pumps can prevent radon from seeping into buildings.

On the global scale, pollution control standards are the result of complex negotiations among nations. Typically, developed countries, having already gone through a period of rapid (and dirty) industrialization, are ready to demand cleaner technologies. Less developed nations, hoping for rapid economic growth, are less enthusiastic about pollution controls. They seek lenient deadlines and financial help from developed countries to make the expensive changes necessary to reduce pollutant emissions in their industrial processes.

Nonetheless, several important international accords have been reached. In 1988 the United States and 24 other nations agreed in the Long-Range Transboundary Air Pollution Agreement to hold their production of nitrogen oxides, a key contributor to acid rain, to current levels. In the Montréal Protocol on Substances that Deplete the Ozone Layer, adopted in 1987 and strengthened in 1990 and 1992, most nations agreed to stop or reduce the manufacture of CFCs. In 1992 the United Nations Framework Convention on Climate Change negotiated a treaty outlining cooperative efforts to curb global warming. The treaty, which took effect in March 1994, has been legally accepted by 160 of the 165 participating countries.

Pollution, Threat to Man's Only Home

We are astronauts—all of us. We ride a spaceship called Earth on its endless journey around the sun. This ship of ours is blessed with life-support systems so ingenious that they are self-renewing, so massive that they can supply the needs of billions.

But for centuries we have taken them for granted, considering their capacity limitless. At last we have begun to monitor the systems, and the findings are deeply disturbing.

Scientists and government officials of the United States and other countries agree that we are in trouble. Unless we stop abusing our vital life-support systems, they will fail. We must maintain them, or pay the penalty. The penalty is death.

Nature Operates in Precarious Balance

Air, water, and land—those are the systems. How do they work?

Look into a pond. A fish feeds there on tiny plants and animals called plankton. In time, the fish dies. Micro-organisms in the water break the creature down into basic chemicals, consuming oxygen from the water in the process. Plant plankton, nourished by those chemicals, produce oxygen to replace it. Animal plankton feed on the plants, fish eat the tiny animals, and the cycle begins anew.

On land, too, nature moves full circle. Living things are nourished there, grow old and die, then decompose to enrich the land again.

A thin envelope of air surrounds the planet. We use its oxygen, exhaling carbon dioxide, which vegetation absorbs. Plants use the carbon for growth by the marvelous process called photosynthesis, and return oxygen to the atmosphere. Thus nature's delicate balance is maintained.

Consider First Our Overloaded Air

For some 'air pollution,' let us give thanks. Dust and other particles in the atmosphere serve as nuclei about which raindrops form. But man has overloaded the sky. For centuries he has pumped particulate matter and gases into the atmosphere. As far back as 1661, a tract on air pollution was published in England.

Today much of the world suffers from the eye-smarting, lung-scarring curse we call smog. In Los Angeles and other great cities it comes in large part from automobile engines.

Last March I braved the streets of Tokyo, in that careening, cacophonous time of day the Japanese call rushawa. I was there for the first International Symposium on Environmental Disruption, where scientists from 13 countries had gathered to exchange views.

'Environmental disruption' was easy enough to see from the window of my taxi. Where else in the world, I wondered, must traffic policemen pause regularly to breathe oxygen. Conditions became so bad last summer that all cars were banned from 122 Tokyo streets on Sundays—the busiest of Japan's shopping days.

In Essen, Germany, I saw disruption in another form—smog caused mainly by industries. The chief of air-pollution control and land protection for North Rhine Westphalia, Dr. Heinrich Stratmann, showed me two small steel squares. The first was bright and new. The second, exposed to the Ruhr's smog for only two months, was chocolate brown and deeply corroded.…

Polluted Air Circles the Earth

We can clean up land before we use it, and purify water before we drink it, but—except in air-conditioned rooms—we must breathe air as it comes to us. Scientists have tracked one type of air pollution—radioactive fallout—twice around the globe. The hazy air I am breathing now in Washington, D. C., may contain sulphur from a Pittsburgh steel mill and carbon monoxide from a Chicago taxi, for this continent's weather patterns often send a river of polluted air flowing southeastward. Someone in Norfolk, Virginia, will be using this air again when I am finished with it.

Automobiles, factories, heating furnaces, power plants, trash incinerators—each adds to the problem, so control is difficult. Compounding that difficulty has been the diversity of agencies responsible for control. Until the President this year established a new Environmental Protection Agency, air-pollution control came chiefly under the Department of Health, Education, and Welfare, water pollution under the Department of the Interior, and land pollution under the Departments of Agriculture, HEW, and Interior.

Now virtually all pollution control is to be directed by one federal agency. But it will still be a complex problem, with much responsibility devolving upon state, county, and municipal governments.

Hard Choice Faces Many Communities

Most states today are ill equipped to monitor the thousands of air-pollution sources within their borders. And, because corrective measures can be tremendously expensive, years may pass before a factory stops spouting black smoke. If a plant has polluted the air for fifty years, and is operating on a close budget—can we, in good conscience, make demands that will drive it into bankruptcy? On the other hand, can we afford to risk our health by continuing to breathe the smoke?

Valley towns, especially, can be smog traps, Missoula, Montana, is such a town. When a layer of stable lifeless air hovers overhead, it holds industrial haze and dust in the valley and gives Missoula an air-pollution intensity that rivals New York City's.

And, of course, there is Los Angeles. 'Smog City, U.S.A.,' some call it. But the Angelenos have tackled their problem head on. Air-pollution regulations there are broader than those the Federal Government has formulated, and the regulations grow tougher year by year. Still, new residents pour into the city, bringing their automobiles. Los Angeles, like the Ruhr, is just managing to keep its smog density from rising.…

Killer Fogs Led to London's Air Cleanup

Twenty years ago London could have claimed the title 'Smog City, Europe.' Three-fourths of its smoke is gone now—a remarkable change triggered by a series of killer fogs in the late 1940's and early 1950's.

The worst of these settled over London on December 5, 1952. For four consecutive days the city's normal daily death rate of 300 more than tripled; in all, some 4,000 extra deaths that winter were blamed on the incident. More such fogs came in the winters that followed. Each took its toll.

In 1956 Parliament passed the Clean Air Act, decreeing that factories and homes in critical areas of the city must switch from soft high-sulphur coal to less smoky fuels: hard coal, gas, electricity, or oil. Inevitably there were economic repercussions, both to householders and to industries. But, with each passing year, London's air grew clearer.

London has proved that the veil of smog can be cast off, but its success story stands almost alone. In sunny Spain, Madrid has joined the ranks of shrouded cities. In Italy, acid from smog cuts into centuries-old sculpture. And each rain here in Washington washes more acid onto our marble buildings and monuments.

The massive struggle to clean our air began so recently that victory seems far off. But we have taken an important step—we realize we must do something. In the frequently quoted words of Pogo, Walt Kelly's cartoon possum, 'We have met the enemy, and he is us.

One by one, the factory smokestacks stop gushing noxious smoke and gases—for it is easier to regulate one factory than it is to depollute ten thousand automobiles. But here in the United States, motor vehicles contribute nearly half our air pollution. A hundred and nine million exhausts spout carbon monoxide, oxides of nitrogen, lead, and a variety of hydrocarbons.

Tetraethyl lead, an additive to most gasolines, is an acknowledged poison, although experts disagree on the long-term effects of small amounts of lead in the human body. Primitive man carried about two milligrams of lead in his bones. Today's city dweller carries 50 to 100 times that amount—up to one-third of what many doctors consider dangerous.

While legislators frame stringent new laws, manufacturers redouble their efforts to develop more efficient emission-control devices and less harmful fuels.

What else can be done to reduce automobile pollution? Increased use of car pools and mass transit would help, say environmentalists. So, perhaps, would engines of more modest horsepower. Others feel such talk is defeatist, except as a short-term measure, and look to new technological advances for the answer.

Gasoline isn't the only fuel available. In San Francisco, I rode in an unusual car. Its engine burned propane, which gives off few pollutants. At least thirty colleges and a number of industrial firms are trying to develop low-pollution engines powered by steam, electricity, or natural gas.

Rivers Overwhelmed by Man's Wastes

Why have so many of America's rivers become casualties as the country grew? Shortsightedness? Not at first. When only a few settlements dotted a river's banks, the sewage that poured in caused little harm. The organic wastes were recycled into nutrients that nourished the tiny forms of life that fed the fish. The river purified itself before it reached the next settlement.

What village could resist using such a convenient disposal system? Pour sewage in, and it disappeared downstream.

Then villages grew into towns. The river reeked a bit on hot summer days, but towns-people knew that the tainted water soon would be disappearing into the 'boundless' sea. The answer to pollution was dilution.

Most towns today remove at least some of the sewage before pouring the wastes into the rivers. Primary plants settle out about a third of the solid matter. More-sophisticated treatment plants add a second step, using bacteria to convert the remaining organic material into inorganic nitrates and phosphates.

But even this disrupts the river's cycle. The 'purified' water is too rich in these nutrients. Detergent wastes add more, and so do the fertilizers that wash in from farmland.

Nitrates and phosphates are food for the water plants such as algae. In the overnourished river, too many algae grow. But algae need sunlight to live. When the algae layer becomes too thick for light to penetrate, the deeper-lying algae die and sink to the river bottom in a thick brown soup. Oxygen is consumed by the decaying algae, making the water uninhabitable by fish.

Thermal pollution, too, afflicts our rivers. When power plants gulp water to cool their steam generators, they return it warmer than before. A temperature rise of just a few degrees can disrupt the breeding habits of fish, 'cook' some of the oxygen out of the water, and increase algal growth.

Industrial chemicals pour into rivers. Pesticides wash in from farm fields. Petroleum products from marine engines and industrial spillage coat the surface, inhibiting the river's oxygen intake. Ohio's oily Cuyahoga River actually caught fire last year and burned two railroad bridges.

Lakes can be even more vulnerable than rivers. Witness Lake Erie, second smallest (after Ontario) and shallowest of the five Great Lakes. No body of fresh water in the country has received more attention than Erie, a lake dying of too much nourishment.

'Lake Erie is suffering from eutrophication,' I was told by Francis T. Mayo, Great Lakes Regional Director of the Federal Water Quality Administration. 'That word comes from the Greek eutrophos, meaning 'well nourished.' A lake becomes overnourished as part of its normal aging process, but man accelerates the process tremendously by pouring in nutrients and industrial chemicals.'

When I asked if Lake Erie could be saved, he nodded. 'It has to be saved. Nobody can afford to write it off.'

But salvation comes hard, I learned. Many industrial plants and municipalities around the lake must change their ways. The tributaries that flow into the lake must be cleaned up—including the inflammable Cuyahoga River. Sewage plants must be upgraded, and agricultural runoff must be controlled.

'Nitrates are very difficult to remove from sewage water,' Mr. Mayo said. 'About 80 percent of the phosphorus can be taken out chemically, though, and that should hold down algae. Once the pollution stops, Erie should begin to clean itself. Its flushing time is only three to five years—that's the time it takes to replace all its water.'

If three to five years seems long, consider Lake Michigan's flushing time: one century! The lake's only outlets are the slow-moving Chicago River and the Straits of Mackinac. Thus Michigan rates special concern from Mr. Mayo and his associates. The lake's pollution load is light—by Erie standards, at least—but any pollution is bound to be there for a long, long time.

Tahoe's Sewage Water Fit to Drink

At an environmental conference in Washington last spring, I was given a glass of water to drink. I sipped with some misgiving, for it was the end product of a sewage plant.

There was an amused glint in the eyes of Frank Sebastian as he watched how slowly I tilted the glass. Mr. Sebastian is Senior Vice President of Envirotech, a California corporation that makes, among other things, tertiary sewage-plant equipment.

'It's purer than the water that comes from your faucets at home,' he said comfortingly.

The water—which tasted like any other water—came from the sewage plant at South Lake Tahoe, California.

Beautiful Lake Tahoe has long been known as one of the purest lakes in the world, but the number of tourists and residents on its shores has skyrocketed in the past two decades. Increasingly, Lake Tahoe was losing the purity that made it so attractive. But for once something was done in time.

'Even secondary sewage treatment wasn't enough,' Mr. Sebastian said, 'so more modern tertiary equipment was installed.

Although the nutrient content of the output water is low, it is not discharged into Lake Tahoe, instead, it is pumped 27 miles into another drainage basin. Dr. Charles R. Goldman, of the University of California, explained why. He is one of the Nation's leading limnologists—lake experts.

'Lake Tahoe has very little flushing action,' he told me. 'Its 37 ½ cubic miles of water are nearly permanent. We just can't add any nitrates and phosphates unnecessarily—even that sewage water. It would aggravate the lake's algal problem.

Algal problem? To me, Lake Tahoe looked as clear as blue crystal. Where were the algae getting their nutrient?

Dr. Goldman reminded me of construction I had seen around the lake. 'If all that bulldozing isn't done very carefully—and often it isn't—topsoil washes into the lake during rains. Nutrients wash in with the soil.

We walked down to the shore. Dr. Goldman felt down between underwater rocks and came up with a handful of green strands.

'There is a lot more of this than there used to be,' he said. 'The lake is still clear enough for sunlight to penetrate about 300 feet and sustain plants down there. If it clouds over with algae or silt, its life-sustaining ability will be greatly reduced.'

When residents of Seattle, Washington, head for the water—and most of them do at every opportunity—they have a choice. Puget Sound stretches along the city's western edge, 20-mile-long Lake Washington on the east.

That lake is important to the people. Ten years ago it was on its way to Lake Erie's fate. Inadequately treated sewage gushed in. A green scum could be seen on the lake's cloudy surface, and the unpleasant stench of dead lake life was hard to ignore on a hot summer day.

Puget Sound was in trouble, too, for seventy million gallons of raw sewage from the Seattle area poured in daily.

In September 1958 the citizens voted Metro into existence—the Municipality of Metropolitan Seattle—to solve the problem. Four up-to-date sewage plants were built, replacing 28 old ones. It was expensive but worthwhile. Discharge of treated wastes into Lake Washington has ended entirely. Output of raw sewage into Puget Sound has virtually stopped.

'Boundless' Seas Are Polluted, Too

A lake, with its clearly defined boundaries, fits comfortably into the human mind. We have no trouble thinking of it as a 'thing.' And if a thing is damaged, we feel that it can be fixed.

But now we realize that our oceans—those 'boundless' seas that cover nearly three-quarters of the planet—are in trouble, too.

'Man puts at least three million tons of oil a year into the oceans,' Dr. Max Blumer, of Woods Hole Oceanographic Institution, told me. 'The yearly total may run as high as ten million tons, which doesn't include tanker wrecks, such as the Torrey Canyon disaster, or production accidents like those off Santa Barbara and Louisiana, either.”

'Unfortunately, most of the spillage happens in just the wrong places,' Dr. Blumer said. 'Spills occur in the coastal waters, where marine productivity is concentrated.'

Like most laymen, I had thought of oil spills in terms of blackened beaches and dying sea birds. Dr. Blumer assured me that the effects were much more far reaching.

'We know more about oil's toxic properties now, because a spill near here—160,000 to 175,000 gallons of number 2 fuel oil—has turned out to be something of a lab experiment in oil pollution and its aftermath.

The spill occurred September 16, 1969, off West Falmouth, Massachusetts. Three days later oceanographers trawled the area. Ninety-five percent of their catch was dead, and the rest was dying.

'Now, a year later, bottom life is still being poisoned,' Dr. Blumer said. 'Toxic substances in the oil have entered the sediment. They seep out and spread with the current. Even after the poison has been diluted a thousand times, it kills shellfish. Where it doesn't kill, it gets into their meat—and it will persist there as long as they live.

More than two million tons of oil a year, Dr. Blumer estimates, come from tankers that flush out their tanks at sea (local laws prevent their doing so in port) and from vessels that pump out oily bilge water. All too often, their wastes drift ashore to foul beaches.

But Dr. Blumer and others are perfecting techniques that 'fingerprint' oil—tell exactly where the oil came from. The day may come when the careless voiding of oil at sea can be traced to a specific ship, and the captain or owners charged with negligence.

In March 1967, when the tanker Torrey Canyon went aground off the British coast, 110,000 tons of oil spilled out. I asked Dr. Blumer what measures could be taken to clean up a huge oil slick of that kind.

'Speed is essential,' he said, 'since the most toxic elements dissolve quickly into the sea water. If the oil can be pumped into airdropped bladders or into another ship … fine. If not, burning is probably the best answer, though that causes air pollution, of course. Containing booms haven't worked out well. Detergents or dispersants may get the problem out of sight, but they do it by sinking the oil down into the marine environment, where it can do more damage.'…

DDT—Boon and Hazard

In 1874 a German chemist named Othmar Zeidler created a new compound. Its jaw-breaking name was dichloro-diphenyltrichloroethane. We know it as DDT.

Dr. Zeidler was unaware that he had found a potential insecticide. Sixty-five years passed before the insecticidal properties were recognized—just before World War II.

DDT was used extensively during the war, against mosquitoes and body lice, with great success. And thousands upon thousands of tons have been used since then, on forests, on farms, and to control household pests. Many an area has been freed at last from malaria.

But one of the compound's most attractive features—the fact that it remains active long after application—has had unpleasant ramifications, too. In the past decade it has become increasingly evident that creatures in water, in air, and on land—including man himself—have built up concentrations within their bodies. Sharp reductions in numbers of ospreys and other birds are attributed to DDT and its derivatives.

The pesticide has traveled through the ocean chain. Even penguins in the Antarctic, where DDT has never been used, have accumulated traces of the compound.

Another senior scientist at Woods Hole Oceanographic Institution, biologist Dr. H. L. Sanders, told me more about the problem.

'It has become apparent that DDT and the other chlorinated hydrocarbon insecticides aren't selective. They are toxic to many forms of animal and marine life. When a fish eats food organisms contaminated with the insecticides, the compound builds up in its fatty tissues. When a larger fish eats him, that predator will end up with the insecticide.

Dr. Sanders is also concerned about another group of toxic chemical compounds—the polychlorinated biphenyls, called PCB's.

'The PCB's have been around for 25 years or so,' he told me. 'But, until recently, we weren't too conscious of them. They are used in the manufacture of plastics, paints, and a great many other things—so they're present in a lot of the industrial waste that ends up in our rivers and oceans. When scientists began analyzing fish samples in a chromatograph to track DDT through the food chain, PCB's kept showing up.

'We've found that they act on marine life much as DDT does, traveling through the food chain. Their toxic effects, alone or in combination, are still largely unknown. Research is just beginning.

Last year Americans threw away 50 billion empty cans, 30 billion glass containers, 4 million tons of plastics, and more than a million television sets. Where did it all go?

Into the ground, mostly, in open dumps or into 'sanitary landfill.' Incineration posed problems: Much of the refuse was unburnable. Also, some burning plastics produce toxic smoke, plus fumes that damage an incinerator's pollution-trapping devices.

Trash Mountain Provides Ski Slopes

Landfill poses problems, too. Leaching chemicals sometimes pollute ground water. Rotting garbage can generate methane gas. Dumping sites for a city's trash are getting more and more difficult to find.

Du Page County, Illinois, just west of Chicago, is trying out a creative solution. Its people are turning a mountain of refuse into a recreational asset. Each day's collection of garbage and trash is spread, tamped firmly, and covered by a six-inch layer of gravel and clay, which controls decomposition and unpleasant odors. So, layer by layer, the hill grows. By July 1971, it will be capped with more clay and soil and, rising some 120 feet, will stand as the highest elevation in the county. Six toboggan runs and five ski slopes will weave down its sides.

What can be done to reduce the astronomical number of discarded cans and bottles? In a number of U. S. cities, the Reynolds Metals Company is buying back aluminum cans for melting and re-use. Returnable bottles are becoming more popular with conservation-minded housewives—for each one reduces trash-disposal problems by making some 20 round trips in the course of its useful life.

I saw an intriguing answer to the bottle problem in Stockholm, Sweden. It was a plastic beer bottle that would gradually turn to dust after it had been drained and discarded. Sunlight's ultraviolet rays work the transition. U.S. and other scientists are working on similar bottles that would break down in sunlight and dissolve in water.

Even atomic scientists are working on the trash problem. Their incinerator would be a 'fusion torch'—using controlled thermonuclear fusion to generate temperatures of millions of degrees. The incredible heat would vaporize trash, reducing it to its basic elements, such as iron, copper, or silicon, for reuse—the ultimate in recycling.

Environmental pollution is not exclusively a city problem. At Cornell University in Ithaca, New York, ecologist Lamont Cole told me about problems down on the farm.

'My grandfather was an Illinois prairie farmer,' he said. 'Granddad rotated his crops, every few years he'd grow alfalfa or red clover and plow it under to replace the humus and nitrogen in the soil. He used lime, but I doubt if he ever bought any artificial fertilizer. After harvesting a crop, he'd turn his animals into the field, and they'd fertilize it.

'Things are different now. Land out there is so valuable that farmers feel they can't afford to do anything except grow corn on it every year, using chemical fertilizers to boost the yield. But unfortunately those chemicals tend to leach out and add to our problems in rivers and lakes.

First Need of All: Population Control

Dr. Cole made another point. I'd heard it made before by virtually every ecologist I had interviewed.

'One of our basic errors,' he said, 'is that we always equate growth with goodness. Everything has to keep growing—the population, the cities, the industries. We have to stop growth somewhere. And, if we don't stop the population explosion, there's very little chance of solving our other problems. It's the key to the whole thing.

'We have to recognize that we're dealing with systems,' he continued. 'For example, the World Health Organization went into Ceylon with pesticides to knock down the high mortality rate from malaria. It did a very good job of it. But its success has also contributed to Ceylon's severe overpopulation problem and strained economy.

'The human race,' the ecologist continued, 'may be in even more trouble than we think. Very possibly, man won't know he has passed the point of no return until it's too late.'

A horrible idea! I asked him to explain.

'Life depends on quite a few microorganisms doing their job,' Dr. Cole replied. 'For example, at least six types of bacteria in soil and water are absolutely essential to keep nitrogen circulating from air into organic material, then back to the air again. If any of the bacteria stopped working, nitrogen in the atmosphere would be depleted—or possibly replaced by ammonia.

He shook his head slowly. 'We're playing a kind of Russian roulette. We keep pouring new chemicals into the environment without testing to see what effect they'll have. If one or a combination of them should ever poison the nitrifying bacteria on a worldwide scale, the air would become unbreathable.'

What about nuclear power plants? Do they pollute the air with radioactivity? I asked the question of Mr. Harlan K. Hoyt, superintendent of Commonwealth Edison's Dresden Nuclear Power Station, 55 miles southwest of Chicago, Illinois.

'Some radioactivity is present in our stack gases,' Mr. Hoyt said. 'But if you lived at the fence line downwind of that stack, you would absorb only one-twentieth as much radioactivity in a year as you would get from one chest X-ray.

But environmentalists worry about any increase in atmospheric radioactivity, and note the growing number of nuclear power plants. When man takes something from his planet, they point out, there may be hidden costs involved. A town lures a new industry by allowing it to contaminate the local river. A jet speeds 150 people across the country, and cloud cover may increase imperceptibly.

'We ecologists have a word for bargains like those,' Dr. Cole said. 'We call them trade-offs. Often the bargains are bad ones.

He paused, searching for the best example. 'Take the Aswan High Dam on the Nile,' he said. 'It was put there to expand irrigation, to generate electricity, and to control the annual flooding of the Nile Valley. Actually, those floods had helped keep the farms productive by fertilizing the land with silt. The dam has virtually ruined a sizable sardine fishery along the Nile Delta, because the nutrient supply has been choked off. The catch has fallen from 18,000 tons a year to less than 500 tons. And there's another problem, too: Snails are spreading through the irrigation ditches, carrying the debilitating disease schistosomiasis.

If Lamont Cole seems to take too jaundiced a view of man's attempts to conquer nature, be assured that he has much company among his ecologist colleagues. Dr. Barry Commoner, Director of the Center for the Biology of Natural Systems at Washington University in St. Louis, Missouri, sums up the matter in speeches on college campuses. Dr. Commoner's three laws of ecology are these: (1) Everything is connected with everything else. (2) Everything goes somewhere. (3) There is no such thing as a free lunch.

Innovations Can Backfire

'It's time that we scientists begin making sure we've asked all the right questions,' Dr. Donald W. Aitken said to me in Palo Alto, California. Dr. Aitken is chairman of environmental studies at San Jose State College.

'Too many times, some technological or engineering advance is conceived and immediately implemented, and ends up having harmful side effects,' he continued.

Dr. Aitken cited the Welland Ship Canal as an example. 'Lamprey eels moved into the Great Lakes through the canal and seriously damaged sport and commercial fishing. What will happen, I wonder, if we build a sea-level canal across Central America and let predators from the Pacific and Caribbean invade each other's realms?'

In Washington I interviewed Dr. Lee A. DuBridge, former President of the California Institute of Technology and until recently President Nixon's Science Advisor. I brought up that matter of asking all the right questions. Had they all been asked before long-lasting pesticides were put into use?

'The side effects of something like DDT show up only after massive use.' Dr. DuBridge replied. 'Similarly, the smog-creating qualities of automobiles weren't apparent until traffic had built up.'

Dr. DuBridge subscribes to the 'no-free-lunch' theory. 'There seems to be a law of nature that every benefit that is introduced to improve our happiness, our welfare, or our security has a cost factor someplace.

'Sometimes it's a dollar factor,' he went on. 'Sometimes it's an environmental factor. And that's the real job for human ingenuity today—to develop concepts that will let us measure the benefits against the risks.'

Mercury: Man's Helper and Poisoner

All of us—including farmers, industrialists, and sewage-plant superintendents—want a clean and healthful world. Then why is our environment being polluted? It comes down to this: Engrossed in our own activities, we have little awareness of side effects that those activities may be having on the world outside. Let me illustrate by following one pollutant—mercury—in its course from helper to poisoner of man.

The first mercury seed dressing was developed half a century ago, and became popular because it inhibited seed mold. Other industries were attracted by those fungicidal abilities. Mercury became common in such businesses as papermaking and diaper laundering; mercury is an important catalyst in the manufacture of a basic plastic, polyvinyl chloride.

But Dr. Barry Commoner's 'no-free-lunch' rule comes into play at this point. Sweden's pheasant population was drastically reduced because the birds ate seeds treated with mercury. Canadians found mercury in partridges and fish. Almost 100 Japanese died from eating fish caught in Minamata Bay—a polyvinyl chloride plant dumped its waste there.

Americans became mercury conscious last July, when fish from 20 states and Canada were found to contain concentrations of the poison. The Department of Justice filed suits against eight U. S. chemical and paper companies, insisting on an immediate halt to water pollution by mercury.

                                                           Air Quality

Air Quality, an indication of the healthfulness of the air based on the quantity of polluting gasses and particulates (liquid droplets or tiny solid particles suspended in air) it contains. Air is considered safe when it contains no harmful chemicals and only low levels of other chemicals that become harmful in higher concentrations to humans, other animals, plants, or their ecosystems.

Air is commonly monitored by the United States Environmental Protection Agency (EPA) and state and local environmental agencies for concentrations of six pollutants: carbon monoxide, lead, nitrogen dioxide, sulfur dioxide, ozone, and particulates. Air samples are collected and analyzed several times daily in cities and other industrial areas. The samples are graded on a scale of 0 to 500, indicating how many parts per million (ppm) contain these pollutants. A sample of 0 to 50 ppm indicates good air quality; 50 to 100 ppm, moderate air quality; 100 to 200 ppm, unhealthy; 200 to 300 ppm, very unhealthy; and 300 to 500 ppm, hazardous. If the concentration of one or more pollutants reaches either the very unhealthy or hazardous categories, people with heart or respiratory problems are warned to stay indoors.

EPA data show an increase in air quality in the United States between 1985 and 1994. During this period, concentrations of carbon monoxide decreased 28 percent; lead, 86 percent; nitrogen dioxide, 9 percent; sulfur dioxide, 25 percent; ozone, 12 percent; and particulates, 20 percent.