JEREMIAH STETTLER, THE SAGINAW NEWS, MAY 13, 2006
DOW: NUMBERS DISTORT RISK
What state regulators tout as “science” seems more like science fiction, Dow Chemical Co. officials say.
The company has released data challenging the state Department of Community Health’s claims that a person who lives and dines along the Tittabawassee River consumes up to 3,900 percent more dioxin than the average adult.
Dow officials say the numbers distort the risks residents face by living along the river — a position they draw on state and federal data to defend.
“What they are presenting to people is a misrepresentation of the facts,” said Dow spokesman John C. Musser. “It infers a lot greater risk than reality.”
The state Department of Environmental Quality joined with state health and agriculture agencies this year to produce a brochure about reducing dioxin exposure at home.
Dioxin is a toxic byproduct of chlorine manufacturing and other industrial processes that scientists have linked to birth defects, weakened immune systems and some forms of cancer in laboratory animals. State officials have unearthed elevated dioxin levels on properties downstream of Dow’s Midland complex.
What rankles Dow leaders is a brochure graphic that details how much dioxin a person might ingest by living along the Tittabawassee River and eating sport fish and wild game harvested from along its banks.
The brochure suggests that people who don’t follow the fish advisories, don’t reduce their exposure to dioxin and eat deer and turkey from the floodplain could suffer 1,000 to 3,900 percent more exposure to dioxin than the average adult.
“Our purpose here is not to destroy industry,” said Linda Dykema, manager of the Department of Community Health’s Toxicology and Response Section. “It is to protect public health. We want people to understand that if they eat the fish they are not supposed to eat and eat the wild game they are not supposed to eat, their exposure is going to be that much higher.”
But Dow officials say the state isn’t giving residents a glimpse of the “real world.” In a detailed critique of the state’s findings, the chemical giant suggested that the study is flawed. Here’s why:
Not every property has dioxin levels of 1,000 parts per trillion — a level that exceeds the state limit 10 fold. Yet health officials use that number in their data.
A Dow spokesman said a more realistic number is about half that. Using soil sampling data from a Department of Community Health probe into more than a dozen Tittabawassee River properties with presumably high dioxin levels, Dow officials found an average dioxin level of 533 parts per trillion.
State officials say they relied on the federal Agency for Toxic Substances and Disease Registry standard and counter that the exposure investigation is in no way represents dioxin level along the entire river.
People don’t eat the same number of white bass, carp and catfish as they do walleye. Yet the state lumps them all together — even though the first three carry much more dioxin — to determine anglers’ diets.
Dow officials point to the state Department of Natural Resource’s annual fishing census, which shows that a mid-Michigan angler’s diet is 85 percent walleye — a fish that the state recently removed from its advisory.
Jim Baker, fisheries unit supervisor for the DNR in Bay City, said the survey does not reflect anglers’ diets. The fish census runs from January to mid-March and from the end of April through May to assess the walleye population in the Tittabawassee River.
While the survey accounts for all fish taken by anglers during that time, it does not reflect the catfish, smallmouth bass and carp — each having higher dioxin levels than walleye — that are taken later in the summer.
People don’t eat two meals of turkey with skin on and two meals of deer liver each year, Dow officials say. They may eat one meal of each, but a second is a bit far-fetched, they say.
State officials disagree. Yet both sides concede that the number of meals — which have a considerable affect on the results — really is a judgment call based more on speculation than science.
Dow’s objections go on. Officials say the state didn’t account for dioxin loss in cooking sport fish or meat, that people don’t really eat 100 milligrams of contaminated soil a day 350 days a year, and that the state included an extra six meals in the diet of its highest dioxin consumer.
“I don’t argue their math,” Musser said. “I argue their assumptions.”
State officials stand behind the data as representative of what is happening in the floodplain. They acknowledge the extra six meals a day, but say it has little substantive impact on the results.
The state’s report concludes that people who disregard the fish advisories, eat contaminated wildlife and do little or nothing to avoid the contamination will ingest up to five times more dioxin per month than the World Health Organization recommends.
Dow’s levels are considerably lower. The levels range from about half the WHO allowance to a maximum concentration about 67 percent higher than the standard.
Even with Dow’s numbers, Dykema said the data show that people who do nothing to limit their dioxin intake will suffer higher exposure than the average adult.
“If Dow has different numbers, so be it,” she said. ” We used numbers that we thought would paint a real world scenario so people could make an informed decision.”
Jeremiah Stettler is a staff writer for The Saginaw News. You may reach him at 776-9685.