Field & Street | Field & Street | Chicago Reader

News & Politics » Field & Street

Field & Street



Twenty years ago Barry Commoner laid out the causes of our environmental crisis in his book The Closing Circle. Our problems, he wrote, arise from our failure to recognize four basic laws of ecology. Law number one says that everything is connected to everything else. Law number two states that everything has to go somewhere. Law number three says that nature knows best. And law number four is the familiar economic argument that there is no such thing as a free lunch.

Everything that has been said since then about our relationship to our environment is essentially a footnote to his basic insight. Those are indeed the rules that govern the biosphere, and every time we trespass against them we run into trouble.

The truth of his second law has hit us again and again over the past two decades. Like most profound statements it can be rephrased in a variety of ways. Everything has to go somewhere also means that throwing something away is an impossibility. It can't be done. No matter how far you throw it, it will never reach the land of away because there is no such place. Every place in the world is in the land of here.

If you don't believe that, I invite you to take a look at such seemingly away places as the mud at the bottom of Waukegan Harbor, Indiana Harbor, Saginaw Bay, the Sheboygan River, and a few dozen other sites around the Great Lakes. For years industries and farmers around the lakes thought they were throwing away their wastes by dumping them in rivers and harbors. The PCBs, DDTs, and hexachlorobenzines, the waste metals, the furans, the PAHs would just sink to the bottom of the lake and be safely out of the way.

The discovery that the bottom of a lake is not in the land of away took several decades. Environmental cleanup of the Great Lakes began in the late 60s. The initial effort was against what are called conventional pollutants, nutrients such as phosphorus that were running into the lakes from sewage-treatment plants and other sources. The excess nutrients upset the balance of the lakes, creating obvious problems like algae blooms and bad smells.

The discovery that life in the lakes was infected with toxic chemicals such as PCBs and DDT came in the early 70s. It led to the banning of these chemicals, and in response to the ban the levels of concentration of these toxics in the tissues of fish and other animals began to fall. But the decline stopped in the late 70s. Clearly there was some source, or sources, of these poisons that was unaffected by the ban.

Scientists looked first at the air as a possible source. The discovery of Mirex in the tissues of fish from Lake Siskiwit provided dramatic confirmation that airborne sources were indeed significant. Lake Siskiwit is a small lake on Isle Royale, a wilderness island in Lake Superior about 20 miles from the nearest shore. Mirex is a pesticide used by cotton growers. The nearest possible source for the Lake Siskiwit Mirex was Mississippi.

But deposits from the air could not account for all the toxics in Great Lakes fish, and that fact turned scientists' attention to the sediments that once seemed the very definition of away. Since the nasty stuff had originated on land, it tended to be concentrated in the shallow, inshore waters of estuaries and harbors. In such environments the sediments were constantly stirred up by the propellers of passing ships and by currents and storm waves. Each perturbation released more poisons into the water.

Dredging provided more disturbance. Many of the worst concentrations--the "hot spots," as people in the environment business say--were in harbors and channels that had to be dredged regularly to keep them navigable. Until quite recently the dredge spoils were simply taken out into deeper water and dumped, an action that spread the toxics into the open lake.

And then there are the animals. Bottom mud is full of life. Sludge worms, crustaceans, clams, mussels, and insect larvae burrow in it. Many of them feed by passing the mud through their bodies and absorbing the edible parts. Along with those edible parts, they take in PCBs and PAHs and heavy metals. These chemicals build up in their bodies, and when a crawdad or bullhead comes along and eats a mud dweller it takes in a very large dose of toxics. And the perch that eats the crawdad and the lake trout that eats the bullhead get even bigger doses. Animals at the top of the food chain contain concentrations of these chemicals many thousands of times larger than the levels in animals at the bottom of the chain.

Bioaccumulation, as this process of concentration is called, has forced a rethinking of the whole question of pollution control. Natural aquatic systems can take in a certain amount of conventional pollutants like phosphorus or nitrates. These chemicals can be cycled through the ecosystem in modest amounts without disrupting anything. So the EPA can issue permits to industries or sewage-treatment plants that allow them to discharge limited amounts of these chemicals.

But there is no safe level for PCBs or dioxins. Early versions of the Clean Water Act called for zero discharge of harmful chemicals. That idea was ignored for years, but now it is being picked up again. The International Joint Commission, the appointive body set up by treaty to govern the waters shared by the U.S. and Canada, has called for the "virtual elimination" of discharges of persistent bioaccumulative toxics, and the EPA is moving, slowly and gingerly, toward putting together a list of chemicals that will be banned to achieve zero discharge.

Spurring this activity is mounting epidemiological evidence of the harm that this bad stuff can do. Almost every time you run across the letters PCB in the media you also find the words "cancer causing," but we now know that the carcinogenic potential of this group of chemicals is not their most serious problem. PCBs are mimics. Our bodies react to them as if they were hormones. They create serious developmental disorders.

Investigators at Wayne State University in Detroit are doing a long-term study of children born to mothers who frequently ate Great Lakes fish before and during their pregnancies. Their children were born smaller than average and less well developed. You get similar results with women who smoke or drink during pregnancy, but those children tend to catch up. By the time they are five, they can't be told from the children of nonsmoking teetotalers. But PCB children don't catch up. They are still behind at the age of five.

If our experience with contaminated sediments illustrates the truth of Commoner's second law, the actions we have to take now demonstrate the truth of his fourth law. No matter how well buffered we believe ourselves to be, the damage we do to the environment will eventually have to be paid for, either with the health of our children or with our money.

Zero discharge can prevent further pollution of our lake bottoms, but cleaning up the mess that is already there is going to be difficult and expensive. A number of companies have moved into the business of cleaning up sediments. A "low-temperature thermal" extraction process was used to remove the PCBs from Waukegan Harbor. Other processes are being tested at other sites around the lakes. Some systems use solvents to extract the toxics. The EPA is currently testing a method that uses bacteria to break down PCB molecules along the Sheboygan River in Wisconsin. Naturally occurring bacteria do attack these chemicals and can reduce them to water, carbon dioxide, and hydrochloric acid. The problem is that the natural process is very slow. If we leave the PCBs on the bottom and wait for the bugs to destroy them, it could be centuries before a safe level is reached.

Even with the best available technology and an adequate supply of money to do the job, cleanups at our worst sites will take years. Pumping tens of thousands of cubic yards of bottom mud through a cleaning machine of some sort takes time.

Most of our problems with contaminated sediments involve chemicals made by humans for some specific industrial purpose. They cannot be efficiently reabsorbed into the environment by the actions of natural processes. Their continuing harmful nature demonstrates the truth of Commoner's third law: Nature knows best.

Commoner will be the featured speaker at a conference sponsored by Greenpeace at the Saint Mary Center in Monroe, Michigan, December 4 through 6. The conference will explore the actions that will have to be taken to create chlorine-free Great Lakes. For further information contact Bonnie Rice, Greenpeace, 1017 W. Jackson, Chicago, IL 60607, or call 666-3305.

Add a comment