A third round of testing residents in three Washington County communities to gauge their exposure to PFCs will begin next week, the Minnesota Department of Health announced Wednesday.
The biomonitoring will determine the effectiveness of measures taken to reduce exposures to PFCs — perfluorochemicals, a family of compounds formerly manufactured by 3M Co. but that are still used.
The East Metro PFC3 Biomonitoring Project will begin with a mailing to selected residents of Oakdale, Lake Elmo and Cottage Grove to inform them of the study.
Some drinking water sources in those communities were contaminated with PFCs from legal and permitted dumping sites used by 3M over several decades and from the company's manufacturing plant in Cottage Grove. 3M stopped making the compounds in 2002, but they are still found in an array of consumer products such as fast-food wrappers, pizza boxes and waterproof clothing, making them among the most ubiquitous compounds on Earth. It's estimated that 98 percent of Americans have PFCs in their systems.
3M, embroiled in a three-year-old, multimillion-dollar lawsuit with the state over alleged damages from PFC dumping, asserts that PFCs pose no proven human health hazard. The chemicals are, however, coming under more intense scrutiny at the state, federal and global levels after numerous studies have found possible associations with cancers, thyroid problems and high cholesterol.
In 2006, after high levels of PFCs were found, the Health Department mobilized to intervene, providing filters to private wells, hooking some residents up to city water supplies and installing treatment filters in the city water systems. 3M has spent an estimated $100 million on cleanup.
The Health Department's first biomonitoring study in 2008 found that participants had PFC levels substantially higher than those found in the general population of the United States.
That study looked at the three most common types of PFCs — PFOA, PFOS and PFHxS. Highest levels were found in older people, long-term residents and men. By 2010, after a second round of testing, levels of all three types of PFCs had fallen between 13 and 26 percent.
For that reason, an advisory panel (which included a member from 3M) to the Health Department recommended that the biomonitoring program not only be extended to see whether that downward trend continues, but also that the sampling size be enlarged to get a clearer picture of how PFC levels compare among different groups of people and what reduces PFC exposure.
Funding for the PFC biomonitoring program was not included in the governor's 2014-15 budget plan but $626,000 was added to a bill by local lawmakers.
Study's main questions
The Health Department said the new study will pursue two main questions. The first is whether PFC levels are still going down. To answer, participants in past studies will be asked to again have their blood drawn and analyzed.
The second question focuses on Oakdale and whether residents who moved there after the 2006 intervention have PFC levels comparable to the general U.S. population and whether those levels are related to the length of their residence.
"We hope that the community members we contact in the next few weeks will read our materials and consider being part of the project," said Jessica Nelson, the Health Department's program coordinator.