Environmental Protection Agency risk assessments indicate that the drinking water concentration representing a one in a 100,000 cancer risk level for 1,4-dioxane is 3.5 parts per billion, and for a one in a million cancer risk it is .35 ppb. Only three states still have double-digit drinking water guidelines for dioxane: New York, South Carolina, and Michigan. Obviously, what is “safe” is subject to subject to interpretation, and is influenced by many variables. But there is growing awareness that what is safe for you, may not be safe for your children or grandchildren.
David Fair (DF): Until 1995, the level of dioxane allowed in Michigan’s drinking water was only 3 ppb. Currently, it’s 85 ppb. The Michigan Department of Environmental Quality has proposed a new, more protective standard at 7.2 parts per billion, still higher that pre-’95 levels. Our Barbara Lucas wonders, is that a safe level for children? Especially for households on well water in the path of Ann Arbor’s dioxane plume? That’sthe focus of this 16th installment of WEMU’s Green Room series on the Ann Arbor Area’s 1,4, dioxane plume.
Christine Shroeder: It is a nice little tucked away neighborhood.
Barbara Lucas (BL): We’re across Wagner Road from the former Gelman Sciences. The Westover Street neighborhood was hard hit when dioxane spread into wells here, beginning almost fifty years ago. Residents drank parts per billion of dioxane in the hundreds before being hooked up to city water in the 1990s.
Shroeder: I was thrilled to find a house here.
BL: Christine Schroeder is a former resident of the street. Last week over coffee, she offered to contact her old neighbors.
Shroeder: I would like to know the long term effects of this. I would like to know how it's affected the people that I lived close to.
BL: But no one answers the doors we knock on, except at one house, and they don’t want to talk on the record.
Shroeder: Do you remember me—Chris—I used to live next door? How are you?
BL: They tell us about a 1991 lawsuit. Families tried to get Gelman to pay for the costs of monitoring their children’s health. They lost. Apparently, the judge threw out the case in five minutes. Chris says that by the time she moved to the neighborhood in 1997…
Schroeder: It astounded me that it was kind of hush-hush. There was no organization within the neighborhood to question or to push or to find out really how this would affect us.
BL: Should there be follow-up of people who drank dioxane at high levels, especially of those exposed when young, considering the vulnerability of children’s developing bodies? Speaking at a town hall meeting in April, here’s Bob Wagner of the Michigan Department of Environmental Quality.
Bob Wagner: Body weight matters with respect to exposure to any chemical.
BL: Wagner says when calculating safe levels, although Michigan uses an average weight of 80 Kg—or 176 pounds—the proposed 7.2 drinking water standard is protective of children.
Wagner: So we account for those age categories in terms of the child receptor, and we also look at their ingestion rate of water, because it is different than adults. I just wanted you to know that is all part of the calculation of the 7.2. We can give you all of those details.
BL: We know that children need more water in proportion to their body weight than do adults. And their bodies are smaller. Yet, the number proposed in Michigan is double the federal recommendations for the same risk level. The logic didn’t make sense to some in the town hall audience.
Attendee #1: That’s really kind of fudging it isn’t it? Because the way you are calculating it doesn’t account for the fact that toxins almost always affect children more.
Attendee #2: We need to be looking at pushing the limits lower. The rest of the world is using 1 to 3 ppb, and in places under 1 ppb, for drinking water. The average weight that was given here—80 kilos—that’s 176 pounds and I can’t imagine a child being at that average weight for the entirety of their childhood!
BL: The proposed 7.2 number is far lower than Michigan’s current 85 ppb limit. But to some, it still looks sky high. Trevor Weigle is Health Officer near a landfill leaching dioxane in Mt. Olive, New Jersey. Last year New Jersey’s allowable dioxane level went from 3 to only .4 ppb.
Trevor Weigle: I don’t know why someone would adopt a less stringent level than the federal government does. How can you say, “I don’t think it’s as bad as the federal government does”?
Barbara Lucas, 89 One, WEMU News.
Resources:
Water intake and hydration physiology during childhood
