The Not-So-Great Lakes: A Legacy of Pollution
July - August 2008
This is the third article in a five-part series.
Cheap shipping and water for processing and cooling have long made the shoreline and major tributaries of the Great Lakes attractive to steel and chemical plants, breweries, automobile factories, and other industries. Unfortunately, many of these facilities and municipal sewage systems have had lengthy histories of pollution problems. Less than 50 years ago Lake Erie was considered dead, the victim of oxygen depleting algae blooms and raw sewage. Around the other Great Lakes, birds of prey were being born with deformities caused by toxic materials in the food chain, and beaches were being closed because of high bacteria counts.
Then, a complex set of federal and state regulations, called for by the Federal Clean Water Act, of 1972, began to produce results. Levels of most pollutants were drastically reduced in the Great Lakes but problems and problem areas remain. There is a polluter’s legacy manifested in what bureaucrats refer to as “areas of concern (AOCs).” These are fairly large geographic areas where contaminants still impair our ability to use the water.
We have entered a period when the pollution at the ends of pipes has dropped, suggesting we are making progress. But then maybe miles down the beach we are witnessing some of the worst algae and bacteria problems seen in years. Public beaches are still being closed every summer and lakefront property owners are still spending less time swimming then they are cleaning up messes. This is occurring because the Great Lakes were abused for such a long time and are undergoing unprecedented changes that exacerbate the affect of certain contaminants on water quality. It’s a dynamic system and it’s getting harder to say if and when better days are coming.
The U.S. and Canadian governments have identified more than 40 AOCs in the Great Lakes. Thirteen of those AOCs are in Michigan (see map) and were in the news recently after an unreleased federal report linked the prevalence of chemical contaminants with health problems. The Center for Disease Control’s 400-page document, publicized by a Washington, D.C. citizens group, stated that people living near and using the Great Lakes had more health problems than their inland-dwelling counterparts. For example, the report associated discharges of lead, mercury, polychlorinated biphenyls (PCBs) and other pollutants in lower Lake Huron with high rates of infant mortality, and deaths from breast, colon and lung cancer, coronary heart disease, and stroke.
The study’s primary author and some scientists who have reviewed the report charge that it is not being officially released by the Center for Disease Control because the findings are so disturbing. Officials at the CDC maintain there is no cover-up; they say the report has not been released yet because of concerns about the methods used. It is very difficult to establish direct cause-and effect relationships among any pollutants and human health indicators because confounding factors such as age, occupation-related stress, ethnicity, and obesity affect disease. Yet, even conservative scientists concede there are compelling reasons for taking the report seriously.
Michigan’s AOCs are associated with factories such as White Lake’s Hooker Chemical Company plant on the Lake Michigan shoreline, various landfills, and bays where combined sewer overflows and multiple industries have discharged for generations. “Legacy pollutants,” those that can persist in the environment for decades, are reducing water quality. This indicates that while regulating the sources of pollution is critically important, it does not equate with restoration. Pollutants persist in sediments, change forms, and bio-accumulate in the food chain—they don’t magically disappear.
Legacy pollutants are at the center of many major legal disputes including one involving Dow Chemical. The company’s Midland plant has long discharged dioxins, which have many forms including some that are likely cancer-causing. The company discharges into the Tittabawassee River, a tributary of the Saginaw River and Lake Huron’s Saginaw Bay. The U.S. Environmental Protection Agency and Michigan Department of Environmental Quality have regulated Dow’s outflows for decades and supervised Dow’s efforts to clean up the riverbeds. But last fall, a sample taken from the Saginaw River revealed what a top EPA scientist called the highest level of dioxin contamination ever recorded. The testing and clean up issues will likely be disputed in courts for a long time while citizens have to worry about contaminants that may have already been around for 50 years. Fish eating advisories have been in effect for years on the Tittibawassee River, and the Michigan Department of Public Health recently advised against eating deer, turkey and other species taken near the River.
Pollution in the Great Lakes is pervasive as well as long-lived. Especially in Lake Superior, non-point source pollution from the atmosphere is very significant. Atmospheric sources account for more than 90 percent of the total loadings of mercury and PCBs in Lake Superior.
The levels of PCBs and persistent organic pollutants (POPs) in Superior, as well as the other Great Lakes, declined sharply after bans went into affect in the 1960s and 70s. But it has since become apparent that POPs literally rain down on the Great Lakes from air that comes from all over the Northern Hemisphere. That explains, for example, why toxaphene—a widely used pesticide—has increased by 50 percent in Lake Superior after its use in the U.S. was banned in 1982. Clearly, controlling POPs would require regulation on a global scale. And the U.S. has a poor track record in supporting international attempts to control mobile pollutants.
Despite 50 years of local and regional pollution control, Great Lakes fish are not entirely safe to eat. Advisories to restrict consumption of fish owing to bioaccumulated chemicals are in effect over many parts of the Great Lakes Basin. With exception of toxaphene, levels of contaminants are at least slowly decreasing. Yet, scientists continue to document increased levels in humans that eat more fish. In fact, people who consumed Great Lakes sport fish for more than 15 years now have contaminant levels in their blood that are two to four times higher than in non-fish eating humans.
This revelation comes as new health threats are being discovered in drinking water supplies. More than 100 different pharmaceuticals such as antibiotics, mood stabilizers, and sex hormones have been detected in U.S. waters, including some in the Great Lakes. This is the direct result of non-absorbed, unmetabolized medicines passing through humans and into sewage outflows. According to the EPA there is no sewage treatment specifically designed to remove pharmaceuticals. The impacts of such contaminants in the Great Lakes has not been studied, but in other waterways across the globe, researchers are linking pharmaceuticals to male fish showing feminine characteristics. The EPA is starting to take the potential threat to humans very seriously.
Toxic materials are only part of the array of pollution problems in the Great Lakes. Reduction of phosphorous—which can cause concentrated blooms of algae and excessive growth of other aquatic plants—has been an important objective of the Great Lakes Water Quality Agreements between Canada and the U.S for 40 years. Phosphorous is released in municipal and industrial sewage, and also comes from runoff of agricultural lands and fertilized lawns. There is interest in a statewide ban of phosphorous in fertilizers, a step seen as a logical and important extension of Michigan’s ban of phosphorous in laundry detergent in the 1970s. But as in the case of toxic pollutants, bans won’t entirely solve the problem. That’s because the phosphorous already in the Great Lakes is consistently recycled.
Since the 1970s, intensive monitoring at selected stations in the Great Lakes has revealed wide variations in phosphorous levels within and between years. At one station in Western Lake Erie, there was an overall downward trend from 1976 to 1999. But there was also evidence of an increase from 1999 to 2004 that seemed to have little to do with phosphorous loading from point or non-point sources. It was likely related to wave action and turbidity that moved phosphorous from the sediments. Complicating analyses further, the invasions of zebra and quagga mussels have likely reduced suspended particles that bind phosphorous and that reduces phosphorous readings in the water column. This underscores the dynamic nature of pollution in the Great Lakes and why the status of the earth’s largest body of fresh water is so hard to assess.
Dr. Patrick J. Rusz
Director of Wildlife Programs
This is the third article in a five-part series.
Cheap shipping and water for processing and cooling have long made the shoreline and major tributaries of the Great Lakes attractive to steel and chemical plants, breweries, automobile factories, and other industries. Unfortunately, many of these facilities and municipal sewage systems have had lengthy histories of pollution problems. Less than 50 years ago Lake Erie was considered dead, the victim of oxygen depleting algae blooms and raw sewage. Around the other Great Lakes, birds of prey were being born with deformities caused by toxic materials in the food chain, and beaches were being closed because of high bacteria counts.
Then, a complex set of federal and state regulations, called for by the Federal Clean Water Act, of 1972, began to produce results. Levels of most pollutants were drastically reduced in the Great Lakes but problems and problem areas remain. There is a polluter’s legacy manifested in what bureaucrats refer to as “areas of concern (AOCs).” These are fairly large geographic areas where contaminants still impair our ability to use the water.
We have entered a period when the pollution at the ends of pipes has dropped, suggesting we are making progress. But then maybe miles down the beach we are witnessing some of the worst algae and bacteria problems seen in years. Public beaches are still being closed every summer and lakefront property owners are still spending less time swimming then they are cleaning up messes. This is occurring because the Great Lakes were abused for such a long time and are undergoing unprecedented changes that exacerbate the affect of certain contaminants on water quality. It’s a dynamic system and it’s getting harder to say if and when better days are coming.
The U.S. and Canadian governments have identified more than 40 AOCs in the Great Lakes. Thirteen of those AOCs are in Michigan (see map) and were in the news recently after an unreleased federal report linked the prevalence of chemical contaminants with health problems. The Center for Disease Control’s 400-page document, publicized by a Washington, D.C. citizens group, stated that people living near and using the Great Lakes had more health problems than their inland-dwelling counterparts. For example, the report associated discharges of lead, mercury, polychlorinated biphenyls (PCBs) and other pollutants in lower Lake Huron with high rates of infant mortality, and deaths from breast, colon and lung cancer, coronary heart disease, and stroke.
The study’s primary author and some scientists who have reviewed the report charge that it is not being officially released by the Center for Disease Control because the findings are so disturbing. Officials at the CDC maintain there is no cover-up; they say the report has not been released yet because of concerns about the methods used. It is very difficult to establish direct cause-and effect relationships among any pollutants and human health indicators because confounding factors such as age, occupation-related stress, ethnicity, and obesity affect disease. Yet, even conservative scientists concede there are compelling reasons for taking the report seriously.
Michigan’s AOCs are associated with factories such as White Lake’s Hooker Chemical Company plant on the Lake Michigan shoreline, various landfills, and bays where combined sewer overflows and multiple industries have discharged for generations. “Legacy pollutants,” those that can persist in the environment for decades, are reducing water quality. This indicates that while regulating the sources of pollution is critically important, it does not equate with restoration. Pollutants persist in sediments, change forms, and bio-accumulate in the food chain—they don’t magically disappear.
Legacy pollutants are at the center of many major legal disputes including one involving Dow Chemical. The company’s Midland plant has long discharged dioxins, which have many forms including some that are likely cancer-causing. The company discharges into the Tittabawassee River, a tributary of the Saginaw River and Lake Huron’s Saginaw Bay. The U.S. Environmental Protection Agency and Michigan Department of Environmental Quality have regulated Dow’s outflows for decades and supervised Dow’s efforts to clean up the riverbeds. But last fall, a sample taken from the Saginaw River revealed what a top EPA scientist called the highest level of dioxin contamination ever recorded. The testing and clean up issues will likely be disputed in courts for a long time while citizens have to worry about contaminants that may have already been around for 50 years. Fish eating advisories have been in effect for years on the Tittibawassee River, and the Michigan Department of Public Health recently advised against eating deer, turkey and other species taken near the River.
Pollution in the Great Lakes is pervasive as well as long-lived. Especially in Lake Superior, non-point source pollution from the atmosphere is very significant. Atmospheric sources account for more than 90 percent of the total loadings of mercury and PCBs in Lake Superior.
The levels of PCBs and persistent organic pollutants (POPs) in Superior, as well as the other Great Lakes, declined sharply after bans went into affect in the 1960s and 70s. But it has since become apparent that POPs literally rain down on the Great Lakes from air that comes from all over the Northern Hemisphere. That explains, for example, why toxaphene—a widely used pesticide—has increased by 50 percent in Lake Superior after its use in the U.S. was banned in 1982. Clearly, controlling POPs would require regulation on a global scale. And the U.S. has a poor track record in supporting international attempts to control mobile pollutants.
Despite 50 years of local and regional pollution control, Great Lakes fish are not entirely safe to eat. Advisories to restrict consumption of fish owing to bioaccumulated chemicals are in effect over many parts of the Great Lakes Basin. With exception of toxaphene, levels of contaminants are at least slowly decreasing. Yet, scientists continue to document increased levels in humans that eat more fish. In fact, people who consumed Great Lakes sport fish for more than 15 years now have contaminant levels in their blood that are two to four times higher than in non-fish eating humans.
This revelation comes as new health threats are being discovered in drinking water supplies. More than 100 different pharmaceuticals such as antibiotics, mood stabilizers, and sex hormones have been detected in U.S. waters, including some in the Great Lakes. This is the direct result of non-absorbed, unmetabolized medicines passing through humans and into sewage outflows. According to the EPA there is no sewage treatment specifically designed to remove pharmaceuticals. The impacts of such contaminants in the Great Lakes has not been studied, but in other waterways across the globe, researchers are linking pharmaceuticals to male fish showing feminine characteristics. The EPA is starting to take the potential threat to humans very seriously.
Toxic materials are only part of the array of pollution problems in the Great Lakes. Reduction of phosphorous—which can cause concentrated blooms of algae and excessive growth of other aquatic plants—has been an important objective of the Great Lakes Water Quality Agreements between Canada and the U.S for 40 years. Phosphorous is released in municipal and industrial sewage, and also comes from runoff of agricultural lands and fertilized lawns. There is interest in a statewide ban of phosphorous in fertilizers, a step seen as a logical and important extension of Michigan’s ban of phosphorous in laundry detergent in the 1970s. But as in the case of toxic pollutants, bans won’t entirely solve the problem. That’s because the phosphorous already in the Great Lakes is consistently recycled.
Since the 1970s, intensive monitoring at selected stations in the Great Lakes has revealed wide variations in phosphorous levels within and between years. At one station in Western Lake Erie, there was an overall downward trend from 1976 to 1999. But there was also evidence of an increase from 1999 to 2004 that seemed to have little to do with phosphorous loading from point or non-point sources. It was likely related to wave action and turbidity that moved phosphorous from the sediments. Complicating analyses further, the invasions of zebra and quagga mussels have likely reduced suspended particles that bind phosphorous and that reduces phosphorous readings in the water column. This underscores the dynamic nature of pollution in the Great Lakes and why the status of the earth’s largest body of fresh water is so hard to assess.
Dr. Patrick J. Rusz
Director of Wildlife Programs