1953
3M scientist Patsy Sherman’s accident leads to creation of Scotchgard. She spills a mixture on a lab assistant’s tennis shoe. The stain turns out to be impervious to water, soap and scrubbing.
1956
3M introduces Scotchgard line of fabric protectors.
1978
3M becomes aware perfluorinated chemicals are present in the blood of its plant workers.
1978
3M lab studies show perfluorinated chemicals are toxic to rhesus monkeys.
1981
DuPont finds evidence of birth defects in babies born to female employees who worked in its chemical plant in West Virginia.
1981
Rich Purdy joins 3M as an eco-toxicologist. His job is to research 3M’s products’ impact on the environment. Purdy becomes concerned about perfluorinated chemicals, as soon as he sees them.
1989
Fardin Oliaei joins the MPCA after doing research on acid rain and dioxins in Lake Superior. She would later become the agency’s lead scientist on new chemical threats to the environment.
1997
3M learns that the blood supply contains traces of PFOA and PFOS. Company expands testing to include human toxicology and wildlife.
1999
3M becomes aware that PFOA and PFOS are toxic, bio-accumulate and are persistent in the environment.
Feb 2000
Scientist Rich Purdy quits 3M, in part over unhappiness that 3M hasn’t reported all its findings on PFOA and PFOS to the Environmental Protection Agency.
May 2000
3M announces it is pulling Scotchgard, a $325 million a year product, off the market on “principles of responsible environmental management.” The company informs MPCA Commissioner Karen Studders of its decision. The agency does not pursue questions about contamination at 3M’s Cottage Grove plant or locations where 3M wastes were disposed. Federal EPA begins an investigation.
2001
Michigan State University toxicologist John Giesy’s research shows perfluorinated chemicals are present in birds and wildlife around the planet.
2002
Former and current 3M workers in the Decatur, Alabama, plant where Scotchgard was produced sue the company, claiming exposure to chemicals made them sick. That case is pending.
2000-2002
3M phases out original Scotchgard formula and PFOA production at its Cottage Grove plant. Minnesota Pollution Control Agency estimates the plant released 10,000 pounds of fluorocarbon compounds into the Mississippi River in 2001. The estimate includes 2,794 pounds of PFOS and 2,303 pounds of PFOA.
Mar 2002
3M tells MPCA the drinking water at 3M Cottage Grove plant is contaminated with PFOA and PFOS. MPCA’s Superfund managers begin investigation.
Nov 2002
Minnesota Department of Health develops health-based values for drinking water of one part per billion for PFOS, and seven parts per billion for PFOA.
2002
Fardin Oliaei and a University of Minnesota researcher get MPCA funding to test fish in Voyageurs National Park for perfluorinated chemicals. She says half the fish test positive for the chemicals.
Dec 2002
Gov. Tim Pawlenty appoints Sheryl Corrigan of 3M as commissioner of the Minnesota Pollution Control Agency.
2003
Environmental Protection Agency releases preliminary draft risk assessment for PFOA.
2003
Centers for Disease Control and Prevention adds PFOA and PFOS to its national biomonitoring surveillance study.
2004
3M publishes results of blood tests on children. It shows children and adults have similar levels of perfluorinated chemicals, indicating the chemicals cross the placenta while a fetus is in utero.
Jun 2004
MPCA Commissioner Sheryl Corrigan files a letter with Gov. Pawlenty and his senior managers, recusing herself from 3M matters, 18 months after being appointed.
Jun 2004
Minnesota Department of Health releases health consultation for 3M plant, declaring the plant poses an indeterminate public health hazard. MDH recommends a more comprehensive investigation, on the scale of the one underway at the 3M plant in Decatur, Alabama.
Aug 2004
Minnesota Department of Health finds seven residential wells near the Washington County landfill contaminated with low levels of perfluorinated chemicals.
Sept 2004
Neighbors of the Decatur plant sue 3M. They claim perfluorinated chemicals from the plant contaminated their soil and groundwater, and lowered their property values.
Oct 2004
Minnesotans file a class action lawsuit against 3M, claiming chemicals from 3M’s Cottage Grove plant made them sick.
Winter 2005
MPCA, Minnesota Department of Health and 3M embark on a work plan to investigate PFOA and PFOS releases from the 3M Cottage Grove plant and 3M landfills into the Mississippi River and groundwater.
Jan 2005
EPA releases draft risk assessment for PFOA.
Jan 2005
Public drinking water in Oakdale, Minnesota, tests positive for trace amounts of PFOS and PFOA. The suspected sources of the contamination are two landfills where 3M disposed of wastes from its perfluorinated chemical operations.
Print 
PDF