1,4-Dioxane is a suspected human carcinogen and a contaminant of “emerging concern” for the EPA. It has been found in over a thousand public water supplies across the country, including thirty in Michigan. Will those who’ve been exposed to Ann Arbor’s contaminated groundwater develop health issues? It’s a question that may be of concern far beyond our borders, and the focus of our report in "The Green Room."
David Fair (DF): This is 89-1 WEMU, and I’m David Fair. Officials in Ann Arbor and Washtenaw County continue to struggle with how best to deal with a slowly spreading groundwater plume of 1, 4 Dioxane. A random sampling by the U.S. Environmental Protection Agency found traces of the chemical in 12% of tested public water systems. At what levels does dioxane become harmful to humans? There is a lack of research data that would help accurately answer this crucial question. In this 13th installment of WEMU’s “The Green Room” series on the Ann Arbor area’s 1, 4 dioxane plume, Barbara Lucas explores whether there may be a wealth of data right under our noses.
Barbara Lucas (BL): I’m with Dan Bicknell, who’s just shown me where, in 1984, he first discovered dioxane escaping from Gelman Sciences into a nearby lake. Now we’re looking at a pipe gushing water into a creek.
BL: There is dioxane in it, but at least it’s legal. Bicknell says back in 1984, the releases were illegal, because the state didn’t know dioxane was leaving the Gelman property.
Bicknell: The actual complaint that was written by the state said ‘You never told anybody this!’
BL: I’d heard that Gelman’s dioxane releases were legal.
Bicknell: If you look at the permits, dioxane isn’t listed there. And therefore the state did not know!
BL: Later, he sends me the documentation to verify. While I’m looking through it, something else catches my eye: Drinking water wells had parts per billion dioxane concentrations in the hundreds of thousands. Wow, considering the EPA advisory level is only 3.5! Over 50 contaminated drinking water wells: “647 ppb, 7,300 ppb, 180,000 ppb.” Bicknell says levels were so high, some people showered at Weber’s Inn until they got on city water. Has anyone followed up with these folks to see how they’re doing now? I check with the county and the DEQ, and the answer is no. I catch up to U of M toxicologist Dr. Rita Loch-Caruso, at the Ann Arbor Green Fair.
Rita Loch-Caruso: That was really a revelation to me and it’s really a major concern. I don’t think we’re going to find many places where people were exposed to that high of a concentration.
BL: She says it would be very helpful to find out if they’ve had increased health issues compared to the general population. Current calculations of risk of dying from cancer due to dioxane rely on rat studies.
Loch-Caruso: And for the reproductive and developmental toxicity, there is really just almost an absence of information. I have found one rat study, and that’s just not enough.
BL: It’s been three decades, so enough time has gone by for health issues to appear. She says what we learn here, can be crucial information elsewhere as well .
Loch-Caruso: What we are having is a situation where it’s becoming increasingly a concern that the general population may be drinking water that is contaminated with 1,4 dioxane.
BL: Loch-Caruso says the fact that Ann Arbor’s plume is a single chemical makes it invaluable for study purposes.
Loch-Caruso: Because most of the time people are exposed to 1,4-dioxane as part of a solvent mixture. And what we have going on in Washtenaw County right now is really just 1,4-dioxane in our groundwater.
(BL): For instance, at homes near the KL Avenue Landfill Superfund Site in Kalamazoo, drinking wells have a mixture of pollutants. I spoke with Nancy Miller, whose parents moved there in 1955. It’s been ten years since they first discovered the dioxane in their well. Although it registers 39 ppb, they don’t want to switch to city water.
Nancy Miller: You know, as long it is under the old 85 ppb, I want to keep my well! We’ve had this… My mother died in her 99th year, and it didn’t affect her.
BL: Who knows, it’s always possible we’ll find those folks who’ve had high exposures have not fared worse than the general population.
Loch-Caruso: It would be wonderful. I mean wouldn’t that be the preferred answer?
BL: Dr. Loch-Caruso hopes to form a team to track them down and see. We won’t know, until we look.
(BL): Barbara Lucas, 89 One, WEMU News
(DF): The Green Room is a presentation of the WEMU News Department. To hear the first 12-installments of our ongoing series on the Ann Arbor area’s 1,4 dioxane plume visit our webpage at wemu.org.