Whistleblowing scientist accuses 3M of PFAS contamination cover-up in Minnesota
AFTON, Minn. — A former 3M scientist says she now believes executives knew PFAS were potentially harmful long before they shared that information.
It's apparent at Kris Hansen's Afton home that she has a deep love for the environment.
"We've got our tomatoes here and some nice kale around the sides," Hansen said. "It makes me feel good and it's something I used to do a lot with my dad."
But it also inspired her career as a scientist.
"My dad worked at 3M for over 40 years. He was the highest-ranked scientist that they had," she said.
And in 1996 she joined the ranks, too, in the environmental lab. A year later, at 28 years old, Hanson says her boss gave her an assignment: find out what was showing up in random human blood samples.
"I figured out that the interferent was PFOS, which is a fluorochemical compound manufactured, at the time, exclusively by 3M," she said.
3M created PFOS, a specific fluorochemical, for its products. PFOS is now included in a larger group of chemicals known as PFAS.
But Hansen says she didn't know that part in the 90s. To be sure of her findings, Hansen says she tested more samples from across the United States and other countries.
"All of those samples had a strong signal for PFOS," she said.
So she told her boss. This was 1997.
"He looked at it and he said, 'This changes everything,' and he walked into his office. It's a very distinct memory for me," she said.
Hansen says she was "really shaken" by the discovery.
"I felt like I had discovered that PFOS, a compound that was really unique to 3M, was widespread in the general population," she said.
From Hansen's perspective, what followed was inaction.
"I really thought that they would be as kind of appalled and surprised and shocked as I was, and that they would want to say, 'How did this happen and how do we fix it?'" she said. "And I didn't sense that for months."
3M did not want to go on camera, but in a statement said in part: "As the science and technology of PFAS, societal and regulatory expectations, and our expectations of ourselves have evolved, so has how we manage PFAS."
The company also cited its industry-leading exit from making other fluorochemicals and vowed to exit PFAS manufacturing by the end of next year.
"Over decades, 3M has shared significant information about PFAS, including by publishing many of its findings regarding PFAS in publicly available scientific journals dating back to the early 1980s. Those journals were and remain available to the scientific community and the public," the statement read.
Hansen says she tested blood samples from the 50s from Korean War recruits. They were negative.
"It just so happens that was before the commercialization of any 3M fluorochemical products," she said. "At that point, the doubters were quiet."
Hansen says it was in a 1998 meeting with a 3M scientist that she learned her discovery wasn't the first.
"He said, 'I don't understand why they're making such a big deal about this. We knew about this in 1975,'" she said.
Documents released by 3M as part of a 2018 settlement show that an older type of 3M fluorochemical was found in the blood of the general population in the 1970s.
"He had been told not to share that data outside of 3M," she said. "It made me understand that there had been some amount of coverup in the company. And I think it's one thing to lose track of a chemical. Unforgivable. But it's another thing to intentionally cover it up."
Hansen first shared her story with ProPublica, a nonprofit investigative journalism organization.
Wednesday on WCCO 4 News at 10, we'll dive deeper with Hansen, and you'll hear what she says happened when she shared her findings with leaders at 3M.