JEREMIAH STETTLER, THE SAGINAW NEWS, JULY 12, 2006
At the National Academy of Sciences, everyone’s a winner … or so it seems in the day since the scientific society released its critique of the U.S. Environmental Protection Agency’s examination of dioxin.
Environmental groups applauded the academy’s description of dioxin as a “likely” human carcinogen and released statements saying the academy has confirmed that the contamination still is toxic.
The state Department of Environmental Quality trumpeted the results as validating its approach to dioxin cleanup along the Tittabawassee River. While the report calls on the EPA to better justify its conclusions, state officials say it does not reject the methods the department used to determine risk.
Lastly, Dow Chemical Co. touts the academy’s review as a pillar of good science. While the review does not throw out the EPA’s system for calculating risk — a method that assumes that an increase in dioxin equates to an increase in health risks — it states that the agency also should include models that assume no dioxin-related health risks until the toxin reaches a certain level.
The National Academy of Sciences, a nonprofit institution commissioned by Congress, reported Tuesday on its findings regarding the EPA’s dioxin analysis. Scientists did not comment on the agency’s entire 1,800-page report, but focused on the EPA’s discussion of health risks.
Dioxin, a contaminant that plagues properties downstream and downwind of Dow’s Midland complex, is linked to some forms of cancer, reproductive problems and weakened immune systems in laboratory animals.
The academy urged the EPA to better explain its conclusions, assumptions and any uncertainties that swirl about the health risks associated with dioxin.
While scientists split on whether dioxin is a proven cancer causer, they settled on language that the contaminant is “likely to be carcinogenic to humans.”
Scientists urged the EPA to include a model that assumes dioxin must reach a certain threshold before it hurts human health.
The academy’s review is available online at the National Academies Press home page, www.nap.edu. Click on the environmental issues category and look for “Health risks from dioxin and related compounds: Evaluation of the EPA reassessment.” v
Jeremiah Stettler is a staff writer for The Saginaw News. You may reach him at 776-9685.