The 'D' Word
A Michigan community learns about dioxin's effects.
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| Photo courtesy of stock.xchng |
In a hotel conference center in Midland, Mich., residents gathered earlier this year to learn about a chemical compound that has been contaminating their city: dioxin.
Farmers, bankers, clergy and homemakers were invited by the Michigan Department of Environmental Quality (DEQ) and Dow Chemical Co. to find out more about what dioxin is, what it does and whether the levels of contamination on their property are high enough to cause concern.
The term “dioxin” refers to a family of chemical compounds, some of which are highly toxic should they enter the human body.
Scientific studies conducted by Michigan have suggested dangerously high levels of dioxin in the soil and water around Midland and neighboring Saginaw since 2003. These findings inspired an agreement between the state and Dow to clean up the contamination in the City of Midland, the Tittabawasse River, the Saginaw River and Saginaw Bay.
“There are some levels of dioxin anywhere in the state,” said DEQ Press Secretary Robert McCann. “Some areas are higher than others, but not anywhere near as high as it is in Midland.”
The state has identified 130 residences along Midland’s Tittabawassee River with soil levels of dioxin measuring at 1,000 parts per trillion (ppt). These levels are 20 times greater than what the U.S. Agency for Toxic Substances and Disease Registry considers safe soil levels for exposure.
Two compounds within the dioxin group — polyhalogenated dibenzo-p-dioxins and furans — are what the Environmental Protection Agency and Michigan’s DEQ believe are responsible for contaminating Midland and Saginaw. The EPA began studying dioxin levels in this area in 1988 and has been working on the issue with the state environmental office since then.
The two dioxin compounds found by the EPA and the DEQ are not produced naturally, but are a byproduct of the combustion process that occurs at chemical plants.
A soil study conducted by the DEQ in 2003 identified Dow’s Midland plant as “the principal source of dioxin contamination in the Tittabawassee River sediments and the Tittabawasee River flood plain soils.”
 Photo courtesy of U.S. Fish and Wildlife Galleries |
| Industrial pollution, wildfires and volcanic eruptions are all sources of dioxin. |
 Photo courtesy of stock.xchng |
As a result of the findings, several Midland-area homeowners are suing Dow, which is headquartered out of Midland and has a chemical plant within close proximity of their land. They are claiming Dow put them at risk of diseases associated with dioxin.
They also are claiming that dioxin in the soil and water on their property from the Dow plant has greatly reduced the value of their property and prevented them from moving to a less contaminated area.
As “one of the most toxic man-made chemicals,” as DEQ Director Steven Chester labeled it, dioxin in high levels could be linked to chloracne, liver failure, cancer and other diseases.
Chloracne is a skin disease that causes large acne, oily skin and other complications.
The disease is associated most famously with Ukranian President Victor Yushchenko, whose facial disfigurement resulted from intentional dioxin poisoning during his campaign for presidency.
Recent research conducted by Linda Birnbaum, a toxicologist with the EPA who used rats as test subjects, indicates that dioxin can bio-accumulate, meaning its concentrations increase as it goes up the food chain.
If dioxin is present in the soil where an animal feeds, its concentration will increase when that animal is eaten by humans. Where there are more steps in the food chain between the original dioxin source and human consumption, as with most seafood, the concentration increases more — or, bio-accumulates — with each step in the food chain.
“Dioxin gets into the sediment, where it bio-magnifies,” Birnbaum said. “It gets into fish. It gets blown by the atmosphere and settles on crops.”
In Birnbaum’s rat study, protein in the liver attached itself to the dioxin, increased dioxin levels and pulled fat into the liver, causing damage to the organ.
According to EPA officials, the first indication of dioxin chemicals and their negative effects was discovered in 1899, when workers at a chlorinated organics plant showed symptoms of chloracne. This was around the same time chlorine was first produced in factories and sold in the form of bleaching powder.
Birnbaum believes it was also around this time that dioxin chemicals were first identified.
She points out, however, that dioxin is not always man-made.
Natural phenomena, like volcanic eruptions or forest fires, also produce dioxin. The combustion resulting from these events sends dioxin chemicals into the air.
Yet, Birnbaum maintains that the amount of dioxin produced from natural events is not enough to be toxic.
As a result of the public meeting held by Dow and DEQ, state representative John Molenaar, R-Midland, has called for an area-wide cleanup.
The lawsuit, after an appeal from Dow, is now pending in the Michigan Supreme Court.
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