ANN ARBOR, Mich. (AP) — The toxic chemical 1,4-dioxane has been detected in shallow groundwater in Ann Arbor.

The discovery of the chemical beneath Waterworks Park is the latest revelation following new investigations into the plume spreading from the former Gelman Sciences property, MLive ( ) reported.

Michigan Department of Environmental Quality officials said the concentrations are about 2-3 parts per billion, below the department's precautionary screening level for risk of vapor intrusion into buildings. Officials said there isn't an immediate public health risk.

However, some area residents are worried that the discovery of the chemical not far below the surface in a relatively dense neighborhood has the potential for human exposure.

"Migration of contaminants from groundwater into indoor air is a new pathway of exposure in connection with the Gelman Sciences plume that the MDEQ is looking at very closely," the DEQ stated in a news release.

The department has proposed a new vapor-intrusion screening level of 29 parts per billion for when dioxane-contaminated groundwater is in contact with a building foundation.

"The MDEQ's first priority is to protect public health," said Mitch Adelman, DEQ district supervisor. "We are committed to open communications and transparency of our actions in affected communities. We will work with local stakeholders to ensure residents are informed and supported as this process moves forward."

Dioxane can cause kidney and liver damage and respiratory problems. It is classified by the U.S. Environmental Protection Agency as likely to be carcinogenic to humans by all routes of exposure.


Information from: The Ann Arbor News,