JEREMIAH STETTLER, THE SAGINAW NEWS, JULY 11, 2006
The Tittabawassee River is less toxic than once thought, a World Health Organization report suggests.
But it’s still toxic.
The World Health Organization reported findings this month that dramatically downgrade the toxicity of one of the chief contaminants in the Tittabawassee River.
The organization found that a toxin known as 2,3,4,7,8 Pentachlorodibenzofuran — a dioxin-like pollutant that makes up more than half of all contamination in the Tittabawassee River — is about 40 percent less toxic than believed during its 1998 analysis.
The change could mean a 20 percent to 25 percent decrease in the overall toxicity of dioxin contamination downstream of Dow Chemical Co., state Department of Environmental Quality officials say.
Dow spokesman John C. Musser said the report “should be reassuring to people.” He said it supports the company’s position that dioxin levels along the Tittabawassee River pose no imminent health threat to residents.
“We would hope that this, as well as other credible science that comes out, would find its way into policy and reflect in the decisions by the DEQ and Dow in addressing the local situation,” Musser said.
Yet with dioxin levels as high as 8,200 parts per trillion in some parts of the Tittabawassee River — a concentration many times higher than the state standard of 90 parts per trillion — state and federal officials say the toxin still is troubling.
“While the numbers will be lower, they will still be high enough to be of concern,” said Greg Rudloff, corrective action project manager for the U.S. Environmental Protection Agency.
DEQ spokesman Robert McCann said his department plans to incorporate the new numbers, just as it did when the World Health Organization released its 1998 report. He called the report the “best available science” for dealing with dioxin.
“At face value, it seems like there is a lot of merit in what they are proposing,” he said.
Dioxin is an industrial pollutant linked to reproductive problems, weakened immune systems and some forms of cancer in laboratory animals. The World Health Organization also suggested in its report that humans may have a higher resistance to dioxin-related ailments, such as cancer, than laboratory animals.
While the organization added that “the human data set is too limited to be conclusive,” Dow officials say it supports their contention that people are less susceptible to dioxin’s effects than rodents.
State officials counter that although humans are more resistant to dioxin on average, the report also notes wide variations in human health effects that deserve increased protection. v
Jeremiah Stettler is a staff writer for The Saginaw News. You may reach him at 776-9685.