Michigan PFAS by the numbers: How much is unsafe?

Chemicals known as PFAS are befouling sites throughout Michigan, but there’s no consensus on how much of the chemical is unsafe for groundwater. (Photo by J. Carl Ganter/CircleofBlue.org)

Related: Michigan waited years to heed warnings on PFAS dangers, expert says

LANSING — Industrial chemicals known as PFAS have been linked to serious health risks. But nobody agrees on how much is unsafe.

The federal government has yet to develop a nationwide standard for PFAS in drinking water, and few states have crafted regulations of their own. Those that have — including New Jersey, Vermont and Minnesota — all have different standards.

And a recent draft report from the U.S. Centers for Disease Control suggests PFAS could be risky at far lower levels that previously believed.

Confused? You’re not alone.

“It’s really no wonder that the average American is driven to wonder whether their drinking water is safe,” Lisa Daniels, director of Pennsylvania's Bureau of State Drinking Water and president of the Association of State Drinking Water Administrators, told a U.S. House committee this month at a hearing probing PFAS concerns.

Here’s a primer on all the numbers related to PFAS –  shorthand for per- and polyfluoroalkyl substances –  and why they matter.

But first, where did PFAS come from?

Because they can reduce friction, types of PFAS have been used to manufacture everything from Teflon and Scotchgard water repellent to firefighting foam. U.S. manufacturers have largely phased out types of PFAS that are more problematic, but those chemicals are still used internationally to make products that may be imported.

How are PFAS hazardous?

Research is still evolving. The two most studied types of PFAS are called PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate).  The most consistent findings of exposed populations have linked the chemicals to low birth weights, immune system troubles, thyroid problems and cancer, according to the EPA.

How much do the feds say is too much PFAS?

The EPA has no drinking water standard for PFAS. That means the agency has no legal leverage to force a water system to address contamination. In 2016, however, the agency set a health advisory level: 70 parts per trillion for combined PFOA and PFOS over a lifetime. (Think of one part per trillion as a grain of sand in a swimming pool.)  Exposure above the health advisory threshold is seen as a health risk, but the standard is unenforceable.

In June, however, another federal agency offered different guidance.

A draft report from the Agency for Toxic Substances and Disease Registry, part of the Centers for Disease Control, produced a “minimal risk level” far below the EPA threshold: 7 parts per trillion for PFOS and 11 parts per trillion for PFOA.

What do states say?

A few states have come up with their own numbers.

New Jersey recently adopted standards for three kinds of PFAS (14 parts per trillion each for PFOA and 13 parts per trillion each for PFOS and another substance called perfluorooctanoic acid or PFNA).  

Minnesota last year set an advisory level for PFOA at 35 parts per trillion and 27 parts per trillion for PFOS.

Vermont’s 20 parts per trillion drinking water standard applies cumulatively to five different PFAS chemicals.

How much PFAS is too much according to Michigan officials?

Michigan has no formal drinking water standard, but state regulators general defer to EPA’s 70 parts per trillion advisory. In January, the Michigan Department of Environmental Quality set state’s cleanup criteria at that level, allowing Michigan to sue Rockford-based shoe company Wolverine Worldwide — an effort to hold the company accountable for pollution in Kent County.

Michigan health and environmental regulators have generally used the EPA number in communicating health risks.

How much PFAS is in Michigan drinking water?

The Michigan Department of Environmental Quality is testing all state public water supplies and at schools with private wells for PFAS. As of mid-September, results trickled in from 641 of 1,238 samples. The breakdown:

  • 615 sites between 0 and 10 parts per trillion;
  • 25 sites between 10 and 70 parts per trillion;
  • Just one site — Parchment, near Kalamazoo — was above 70 parts per trillion (The town registered more than 20-times the EPA advisory and switched voluntarily its water source with help from the state.)

For specific results, visit this Michigan web page.

Should Michigan set a drinking water standard?

Yes, say environmentalists, community activists and some lawmakers.

Last December, state Rep. Winnie Brinks, D-Grand Rapids, introduced legislation to set a drinking water standard for PFAS at 5 parts per trillion, lower than any other state. She and other Democrats chided House Republicans for failing to schedule a hearing on the bill.

Some experts question the wisdom of allowing lawmakers to set such a scientifically based standard.

“The judgment about that should be made on several lines of evidence” including research in toxicology and environmental engineering, said David Savitz, professor at the Brown University School of Public Health and chairman of Gov. Rick Snyder’s scientific advisory committee on PFAS.

“That is a really complicated, technical judgement, and it can’t be made on just what the public would like to see.”

Brinks said her proposal is based upon research from Philippe Grandjean, a professor of environmental health at Harvard College, who suggests the health threshold should be as low as 1 part per trillion.

“We had to start low, but low enough so we could meaningfully understand what’s in the water. So we landed at 5 [parts per trillion],” Brinks said.

Why not wait for the EPA or DEQ to set a standard?

“Waiting when this stuff is really harmful is not responsible,” Brinks said.

Would a state or federal drinking water standard carry costs?

Sure. It would force contaminated water systems to install special filtration systems or switch to a cleaner water source — neither of which are free.

In a 2017 proposal, New Jersey estimated public drinking water systems would pay about $2,000 for quarterly testing in the first year. And prices for a “granular activated carbon” system that could filter out PFAS ranged from $500,000 to $1 million, according to New Jersey’s Drinking Water Quality Institute, a state research panel.

Keith Cooper, chairman of the institute and a Rutgers University professor, said New Jersey minimized disruption among utilities by phasing in its standards.

“A lot of the water purveyors knew this was coming already,” he said.

So which number should the public care about?

Savitz, the chairman of Snyder’s advisory committee, cautioned against putting too much stock in one number, and instead consider the range for concern recent research has outlined: somewhere between 10 and 70 parts per trillion.

“That may sound like a big difference,” he said. “But in the kind of speculation that goes into making these estimates, that’s actually pretty close to one another.”

And even within that range, health effects aren’t certain, Savitz added.

About this project

Bridge Magazine teamed with Detroit Public Television and Circle of Blue, a Traverse City-based nonprofit, for this special report on the multiple threats to Michigan’s groundwater. The reporting partners will host a live broadcast to discuss the report and similar threats worldwide at 1 p.m. Oct. 1. To register, follow this link.

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Erwin Haas
Wed, 09/26/2018 - 9:21am

The PFAS/C8 kerfuffle is peddled by toxicologists, environmentalists, lawyers, second rate newspapers all of whom hope to profit from creating panic.
The Australians carried out a thorough analysis and found no health effects.

There was a lawsuit against a Dupont plant in Northern W. Virginia.
The company funded a study ;
-showing possible links to high cholesterol, ulcerative colitis, thyroid disease, testicular cancer, kidney cancer, and pregnancy-induced hypertension. This area is in the midst of Appalachia; I know of adults who carry hookworm in Ashland, Ky, 50 miles away and the average lifespan in that region is 4 years shorter for women and 7 years for men, so these folks have a lot of disease. The plant was on one side of the river but it was more convenient to study subjects in Ohio, kind of like the drunk who lost his car keys in the dark alley but looks for them under the streetlight because it’s where he can see. The researchers always appended, "possible", "small" numbers.
I’m running for Michigan's 26th senate district and am the only candidate with the skills and motive to dig into the scientific and business details and keep the “experts” honest.

Wed, 09/26/2018 - 11:47am

Hmm, the Libertarian candidate suggests that regulation of chemicals with poorly understood impact on health is unnecessary. Cites one study, says other study that counters it is wrong. Color me shocked.

Good luck losing again Erwin; maybe in 2020 you'll finally get the chance to make vaccines in Michigan optional.

Erwin Haas
Wed, 09/26/2018 - 7:07pm

No, I cited two studies; one showed no toxic effects and the other was full of possible, might, and other weasel words. I'd suggest getting a better study before getting people, the ones who have to pay for this cleanup and disruption, all excited.
The key phrase here is "Keep the yokels scared and the money never stops." HL Mencken or someone.

Wed, 09/26/2018 - 12:04pm

"Think of 1 part per trillion as a grain of sand in a swimming pool." Did I just read this right?
I'm no scientist but if PFAS is so toxic that one grain can pollute an entire pool of clean water, shouldn't these PFAS compounds be melting our skin or innards on contact? Nobody wants contaminated water but measuring in parts per trillion (ppt) may as well be zero. No other contaminate is measured in parts per trillion. The EPA standard for lead is 15 parts per billion (ppb). If they had a ppt standard, it would be 15,000. Sounds bad 'eh? That means we can safely consume 14,000 ppt of lead in our water. That also means the EPA PFAS advisory level of 70 ppt is only .070 ppb. Is it really that much worse than lead? Sounds a bit like an MDEQ CYA to make up for screwing up the Flint water situation so badly.

Vince Caruso
Sat, 12/15/2018 - 4:16pm

Do folks really think 3M would have settled for close to $1B in damages in MN if this compound was harmless?
It is another Wonder Chemical that has turned out to be 'The Devil We Now Know'. Add it to the list.
We need to jump on this problem with All Hands On Deck and the DEQ needs to get new leadership. Maybe with Whitmer that will see this change that is long overdue.
MI is the Saudi Araba of Fresh Water, let's start treating like it is worth protecting.