'We don't have all the answers'
Minnesota Department of Health officials last week walked Cottage Grove residents through the results of a study that confirmed east metro residents have elevated levels of PFCs in their blood.
Now, local officials say, they want to know what effects the chemicals have had on the health of south Washington County's residents. A study like that, though, would require millions of dollars in hard-to-come-by funding, the department's assistant commissioner said.
"We understand this is a high-priority issue for you," John Linc Stine, the health department's assistant commissioner, told residents. "You live here, you drink the water."
But, he said, there are "many competing priorities for the money a large study would need."
The levels of three perfluorinated chemicals -- 3M-manufactured PFOA and PFOS, and PFHxS, the source of which is not confirmed -- were present in the blood of the 196 east metro residents who had blood sampled at greater levels than compared to the general population.
Half the residents tested were served by private wells in Lake Elmo and Cottage Grove, the other half by the Oakdale city water system.
PFOA was present in tested residents at levels roughly four times higher than the general population -- 15 parts per billion compared to four parts per billion. PFOS showed up in study participants at about one and a half times the general population -- 36 parts per billion compared to 21 parts per billion.
A third chemical, PFHxS was present at four times the national rate.
Jean Johnson, the health department epidemiologist who oversaw the study, said those levels, while elevated over the general U.S. population, are still considered low.
The department is not yet able to definitively determine what the health effects of PFC exposure are. But, Johnson said, based on 3M worker studies conducted in 2000 -- which showed PFCs present in employees at levels up to 100 times greater than the general population -- the department doesn't currently believe there is an increased risk of disease at levels present in the east metro.
"The worker studies have not found an increase in diseases, and they were exposed at a much higher level," Johnson said.
But local officials said last week they want to see south Washington County residents specifically tested.
"I'm not real happy with the response," from the Minnesota Department of Health, Cottage Grove Mayor Myron Bailey said. "I get the (purpose) of the test and I want to see more of what that really means to the residents of Cottage Grove."
Both PFOA and PFOS have been linked to increased incidence of cancer of the liver, pancreas and testes in animals. Research has not conclusively shown, though, that the chemicals cause health problems in humans.
3M spokesman Bill Nelson says he believes the 116-page study represents "a helpful snapshot." But the company, which manufactured products containing PFOA and PFOS until early this decade at its Cottage Grove plant, is "very confident in what the science has said about no adverse health effects."
The bulk of questions from the public at last week's open house revolved around residents' health concerns. And elected officials like Bailey, Sen. Katie Sieben, DFL-Cottage Grove and Rep. Marcia Swails, DFL-Woodbury, all expressed a desire to see further studies done on any connections between PFC-contaminated drinking water and the health of south Washington County residents -- particularly on rates of cancer in south Washington County.
Health department officials, though, say a large-scale study would be a huge effort, requiring millions of dollars unavailable to the department in the midst of a state budget crisis.
Department representatives said a PFC health-effects study in the east metro would likely require involvement from the University of Minnesota or Rochester's Mayo Clinic.
Sieben sponsored the legislation that required the biomonitoring study. She said she would urge the department to begin applying for National Institute of Health grants, another option for covering the steep costs of a PFC exposure health study.
Johnson said further study of the data would be conducted, comparing levels of PFCs in blood samples and water samples to determine if those with the highest concentration in their drinking water also had the highest levels in their blood.
There's still a lot scientists don't know about the chemicals, she said, and the picture is still incomplete.
"We don't have all the answers," Johnson conceded. "We now have one more piece of the puzzle."