PFBA belongs to a class of compounds called perfluorochemicals. At one time 3M used these compounds to make ScotchGard and other stain and water-resistant products. Studies have shown that some of the chemicals are toxic to laboratory animals.
After state officials made their presentations, residents peppered them with questions and criticisms for almost an hour.
Last month the Minnesota Department of Health announced that it had found low levels of perfluorbutanoic acid, or PFBA, in dozens of municipal wells and some private wells in six east metro communities. The cities include Cottage Grove, Woodbury, South St. Paul, Newport, St. Paul Park and Hastings.
Health Department officials say they don't believe PFBA poses an immediate health risk to residents. But they admit that not a lot is known about the compound either.
Risk assessor Jim Kelly told Cottage Grove residents there aren't many studies looking specifically at PFBA. But he said 3M recently concluded a 28-day study of the compound in rats and found that it had a minimal affect.
"We see some very slight effects on the livers of these animals that are exposed to fairly high doses, and it's not a critical effect," he said. "It's not a disease. It's just an effect that we can measure. A change in the weight liver and some of them oddly have a decrease in their cholesterol."
3M and the U.S. Environmental Protection Agency are conducting more toxicity tests on PFBA. The results will be ready later this year.
In the meantime, the health department plans to take more water samples. Hydrogeologist Ginny Yingling said her team is going to focus on areas that have high levels of PFBA nearby and areas with complicated geology.
In places where concentrations appear to be lower, Yingling said the department won't take as many samples. But she said residents shouldn't be discouraged if their well isn't tested.
"Sampling is going to go on as long as it takes for us to ensure that public health is protected, that we've adequately defined the magnitude and the extent of the contamination both across the county and in all of the aquifers," said Yingling.
When officials finally opened up the meeting to questions, Beverly Steichen, 72, was the first person to the microphone. She berated the health department for being too slow and too cautious in its response to the contamination.
Steichen was especially critical of 3M's 28-day rat tests. She said the department should be testing people to find out how much of the chemical is in their blood.
"I've been drinking this water, raised four children with it for 50 years, and my grandkids. It's a little longer than 28 days," said Steichen. "I'd like some test results, not geography lessons."
Resident Chris Christenson said he was disappointed that officials are not supplying bottled water.
The Health Department is not recommending that residents change their drinking water habits. But the department has said that if residents are concerned about their drinking water, they could buy their own bottled water or an activated charcoal filter.
"It sounds like if we're concerned, we're supposed to go buy a filter and install it ourselves," said Christenson, "and it just doesn't sound like the just thing for us to have to do if this is pretty clearly someone else's chemical that may or may not be bad."
Sen. Katie Sieben, DFL-Newport, told residents she is drafting legislation that would require the state to provide bottled water to residents with wells that exceed the department's PFBA limit of one part per billion.
Sieben added she is also working on a bill that would require the state to set up a voluntary biomonitoring program for residents who want to test their blood for perfluorinated chemicals. Several residents were upset that 3M was not at the meeting to answer questions. Officials said they extended an invitation to the company, but 3M declined to send a representative.