The Minnesota Department of Health says it will study for the third time the levels of perfluorochemicals, or PFCs, in the blood of some residents in Washington County.
The biomonitoring project is set to begin next week with mailings to some residents of Oakdale, Lake Elmo, and Cottage Grove, letting them know that some drinking water sources in the area were contaminated by PFCs before a public health intervention in 2006, a statement said.
According to the statement:
Next week's project includes contacting people who participated in past studies to ask them to have their blood drawn. Staff will also randomly select up to 200 adults in Oakdale for testing.
The new study aims to explore whether the levels continue to decline in long-term east metro residents who drank the water before 2006, and whether PFC levels in newer Oakdale residents is linked to the length of time they lived there. Previous biomonitoring projects showed the levels declined between 2008 and 2010.
In 2008, the PFC contamination had been stabilized in the east metro. The groundwater in parts of Oakdale, Lake Elmo, Woodbury and Cottage Grove were previously affected.
Levels of the three main chemicals has declined since a 2008 health department study found evidence of those chemicals, MPR News reported in 2011:
Public and private drinking water supplies in several east metro communities are being filtered to remove the chemicals.
3M made the chemicals until 2002 and disposed of industrial wastes at several landfills in the area where they entered the water supply through ground water.
In 2007, the Minnesota Pollution Control Agency planned to search for PFCs in dozens of active landfills and waste water treatment plants around the state.