Cottage Grove residents to be part of third PFC contamination study
State officials will conduct another study of Cottage Grove and other east-metro residents’ perfluorochemical exposure levels.
The Minnesota Health Department said beginning this week it will ask people in Cottage Grove, Oakdale and Lake Elmo to participate in a third blood sample study to determine whether efforts to reduce PFC exposure have been effective. The study group includes 20 Cottage Grove residents.
The study is part of the department’s ongoing PFC3 Biomonitoring Project. It was launched in 2007 after the discovery that a group of chemicals produced by 3M at its Cottage Grove plant contaminated groundwater at multiple east-metro locations, including a Washington County landfill, an approved dump site near the Cottage Grove-Woodbury border and at the 3M plant near the Mississippi River.
For decades 3M produced PFCs and used them in products it manufactured, but stopped in 2002. Studies conducted by the Health Department after the contamination was discovered showed that east-metro residents who consumed PFC-contaminated drinking water had higher levels of the chemicals in their blood than the national average.
Some Cottage Grove and Lake Elmo residents on private well water that had higher levels of certain PFCs received carbon filtration systems as part of a large cleanup project led by 3M and approved by the state. Some residents received bottled drinking water for a short time before the carbon filtration systems were installed. Oakdale upgraded its city water system after the contamination.
There are two parts to the upcoming study. State officials will mail letters this week to selected residents of the three cities who had consumed contaminated drinking water. Researchers will ask them to have their blood drawn at HealthEast in Oakdale. Those samples will be studied to determine whether their PFC levels are dropping, as they did from 2008 to 2010 following the start of the public health response to the contamination.
Also, the state will analyze PFC levels in newer Oakdale residents using a survey and blood samples.
In 2010, 88 percent of people who took part in the initial blood study agreed to participate in the second blood survey, said Jessica Nelson, a Health Department program coordinator. That is a good rate, but officials wonder if there will be the same level of participation for a third study.
“That is a concern with the longer-term cohort that we will be losing some people each time we go back to them,” Nelson said. “We hope that they’ll see the bigger picture of contributing information for their community.”
People who participate in the blood sample study will have the opportunity to get their individual results before a public release of the study findings, which is expected around March 2015.
As part of the broader biomonitoring project, the Health Department in 2010 and 2011 surveyed 80 residents of Cottage Grove and Lake Elmo, and another 86 Oakdale residents, to learn how they may have been exposed to the PFCs that polluted groundwater. That survey found that generally the longer people had consumed unfiltered drinking water, the higher their level of PFCs.
State officials have said there is no scientific consensus on the health effects of PFC exposure. PFCs are still used in many products, and most people have low levels of the chemicals in their blood.
The state of Minnesota has sued 3M for environmental damage resulting from PFC contamination. That case is pending.