PFAS is Michigan's most widespread, serious contamination problem since the PBB crisis of the 1970s. Thousands of Michigan residents' water supplies have been impacted, and the full scope of the contamination from these so-called "forever chemicals" is not yet known. Soil and surface waters are also contaminated in many places, and people's exposures may have come from consumer products in years past.

Michigan has tested more than 1,700 public drinking water supplies statewide for PFAS compounds — every public water system (even down to a mobile home park with 25 users), every tribal water system, every school and day care/Headstart with its own well. Regulators also have tested residential wells in known areas of PFAS contamination.

PFAS contamination: Michigan's biggest environmental crisis in 40 years

Here is information for understanding the problem, and what can be done about it:

What is PFAS?

Per- and polyfluoroalkyl substances (PFAS), sometimes called PFCs, are a group of chemicals that are resistant to heat, water, and oil. PFAS have been classified by the U.S. Environmental Protection Agency (EPA) as an emerging contaminant on the national landscape. For decades, they have been used in many industrial applications and consumer products such as carpeting, waterproof clothing, upholstery, food paper wrappings, firefighting foams, and metal plating. PFAS have been found at low levels both in the environment and in blood samples of the general U.S. population.



These chemicals are persistent, which means they do not break down in the environment. They also bioaccumulate, meaning the amount builds up over time in the blood and organs.

Where is PFAS found?

Though largely phased out of manufacture and use in the U.S. by 2015, people were —and potentially still are — being exposed to PFAS today. Here's where PFAS compounds can be found:

Food packaged in PFAS-containing materials, processed with equipment that used PFAS, or grown in PFAS-contaminated soil or water.

packaged in PFAS-containing materials, processed with equipment that used PFAS, or grown in PFAS-contaminated soil or water. Commercial household products , including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints, cleaning products, and firefighting foams (a major source of groundwater contamination at airports and military bases where firefighting training occurred).

, including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints, cleaning products, and firefighting foams (a major source of groundwater contamination at airports and military bases where firefighting training occurred). The workplace, including production facilities or industries (e.g., chrome plating, electronics manufacturing or oil recovery) that used PFAS.

including production facilities or industries (e.g., chrome plating, electronics manufacturing or oil recovery) that used PFAS. Drinking water, typically localized and associated with a specific facility (e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility).

typically localized and associated with a specific facility (e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility). Living organisms, including fish, animals and humans, where PFAS have the ability to build up and persist over time.

Have I been exposed?

Almost certainly. Research has shown PFAS compounds can be found in about 99% of Americans' blood.

What are the health concerns associated with PFAS?

Knowledge of how PFAS compounds — of which only a handful have been studied — harm health is still evolving, with many compounds not yet even evaluated. What's known so far are the following health risks:

Pregnancy-induced hypertension/pre-eclampsia (PFOA, PFOS)

Liver damage (PFOA, PFOS, PFHxS)

Increases in LDL or so-called "bad" cholesterol (PFOA, PFOS, PFNA, PFDeA)

Increased risk of thyroid disease (PFOA, PFOS)

Decreased antibody response to vaccines (PFOA, PFOS, PFHxS, PFDeA)

Increased risk of asthma diagnosis (PFOA)

Increased risk of decreased fertility (PFOA, PFOS)

Small decreases in birth weight (PFOA, PFOS)

The International Agency for Research on Cancer has concluded that PFOA is possibly carcinogenic to humans. Increases in testicular and kidney

cancer have been observed in highly exposed humans.

What levels of PFAS are unsafe?

It's a matter of serious debate. The EPA in 2016 revised its health advisory limit for PFOS and PFOA in drinking water to 70 parts per trillion. But a science advisory panel convened by the Michigan PFAS Action Response Team in December announced that limit was probably not adequately protective of human health.

The federal Agency for Toxic Substances and Disease Registry last year established water concentrations below which the agency would not expect health impacts:

PFOA: 78 parts per trillion (ppt) (adult) and 21 ppt (child)

78 parts per trillion (ppt) (adult) and 21 ppt (child) PFOS: 52 ppt (adult) and 14 ppt (child)

52 ppt (adult) and 14 ppt (child) PFHxS: 517 ppt (adult) and 140 ppt (child)

517 ppt (adult) and 140 ppt (child) PFNA: 78 ppt (adult) and 21 ppt (child)

Others, however, believe the thresholds should be far lower to protect public health. California and New Jersey, for example, have set their maximum limits for water at 13 ppt for PFOS and 14 ppt for PFOA.

How many PFAS compounds are there?

No one knows for sure. The U.S. Environmental Protection Agency estimates 5,000 to 10,000 compounds, and maybe more. The two primary PFAS compounds manufactured by 3M Co., DuPont and others are perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). They are the PFAS compounds about which the most is known. Many of the remaining PFAS compounds about which less is known were spinoff products made inadvertently during the manufacturing of PFOS or PFOA, and/or are precursors — compounds that change or break down into becoming PFOS or PFOA.

My drinking water has a funny taste. Is it PFAS?

Not because of the taste; PFAS compounds have no smell or taste. If your water has an unusual taste or color, contact your local health department.

Does PFAS contamination only affect well water?

There is concern regardless of whether you have a private drinking water well or are on a municipal or community water system. The State of Michigan tested community water supplies throughout Michigan for the presence of PFAS compounds. For data on the findings in your community, visit www.michigan.gov/pfasresponse and then click "Testing and Treatment" and "Statewide Testing Initiative." The state has also directed the testing of residential wells in many of the known areas of PFAS contamination.

How do I get my well tested, and does it cost anything?

For details on residential well testing by the State of Michigan, you can contact the state Environmental Assistance Center at 800-662-9278.

If you are not part of an official investigation area and want to sample your own residential well or pay a technician to sample your well, the Michigan PFAS Action Response Team provides information on laboratories located within the state and guidance on how to take a sample of your drinking water. Those without web access can get more information by calling the state Environmental Assistance Center at the number listed above. Each laboratory has its own fee schedule. The State of Michigan does not endorse these labs.

My drinking water contains PFAS. What should I do?

When the amount of PFOA and PFOS exceed the EPA health advisory level of 70 parts per trillion, the Michigan Department of Health and Human Services advises using bottled water or water filtered by a system certified to reduce the amount of PFOA and PFOS.

In this situation, the health department recommends you use the bottled or filtered water for drinking, cooking, making baby formula or food, washing fruits or vegetables, or brushing your teeth. Touching the water is not harmful. You can bathe, wash dishes, launder your cloths, and clean with your well water, according to the Michigan PFAS Action Response Team.

When detections are lower than the EPA health advisory, the health department may still recommend use of bottled or filtered water in situations where it's uncertain whether the chemicals will remain at lower levels. And bear in mind the ongoing debate over whether the 70 parts per trillion advisory level is protective enough.

What kind of home filtration systems can remove PFAS from drinking water?

Water filtration units that use granular activated carbon or reverse osmosis can both be effective in removing at least PFOS and PFOA from water.

Should I inform my doctor?

Yes, if your water tests above the EPA health advisory level. There will likely be a learning curve for your doctor as well on this emerging chemical, but he or she might choose to more regularly monitor aspects of your health that could be threatened by PFAS exposure, including cholesterol and thyroid, liver and kidney.

Do PFAS levels in water stay relatively stable?

PFAS levels can fluctuate significantly in drinking water supplies, particularly if the contaminated groundwater plumes from which the drinking water supply is drawn are uncontrolled. As groundwater naturally flows, and contaminated plumes shift, PFAS levels can rise and fall.

One family in Rockford, affected by a PFAS-contaminated groundwater plume from a nearby landfill, had their home's residential well initially test for PFOS and PFOA at 8,900 parts per trillion. But in weekly water tests, that contamination level has nearly doubled at times. Meanwhile, their neighbor, also on well water, had their water test at only 3 parts per trillion of PFAS.

What is the state doing?

In many locations, alternate water supplies are being provided to those affected; cleanup of the PFAS contamination is not yet occurring. The state Department of Health and Human Services is working with federal and local health officials to conduct exposure assessments of those living in the North Kent County PFAS contamination zone, taking blood samples and information to better gauge exposures.

On even the two most well-known PFAS compounds out of thousands, PFOS and PFOA, the EPA has not yet set a so-called Maximum Contaminant Level, a legal threshold limit on the amount of a substance that is allowed in public water systems under the Safe Drinking Water Act. Michigan Gov. Gretchen Whitmer has proposed that Michigan set its own, enforceable PFAS regulatory limits within the next year.

Is Congress doing anything?

Congress has put $20 million toward studying the potential effects of PFAS exposure nationally, and U.S. Rep. Dan Kildee, R-Flint Township, is helping to lead a bipartisan PFAS task force in the U.S. House that is looking at other responses. Members of Michigan's congressional delegation have also been pushing for the federal government to commit to providing disability benefits to any military personnel or families impacted by PFAS and to clean up PFAS sites.

One more time: What should I do?

If you're on a municipal water system, check to see whether your water tested for PFAS compounds, and at what levels, at the Michigan PFAS Action Response Team website: www.michigan.gov/pfasresponse, then click "Testing and Treatment," then "Statewide Testing Initiative" and search for your city.

to see whether tested for PFAS compounds, and at what levels, at the Michigan PFAS Action Response Team website: www.michigan.gov/pfasresponse, then click "Testing and Treatment," then "Statewide Testing Initiative" and search for your city. If you're on a residential well, you may have your water tested for the most common PFAS compounds, PFOS and PFOA. Call the Michigan Environmental Assistance Center at 800-662-9278 to find out more. This testing will be conducted by a private company, not the state, and costs vary.

for the most common PFAS compounds, PFOS and PFOA. Call the Michigan Environmental Assistance Center at 800-662-9278 to find out more. This testing will be conducted by a private company, not the state, and costs vary. If a PFAS problem exists in your water, obtain and use an appropriate granulated activated carbon or reverse osmosis whole-house or sink filtration system to remove the contaminant. Call the state Environmental Assistance Center help line listed above for more information.

granulated activated carbon or reverse osmosis whole-house or sink to remove the contaminant. Call the state Environmental Assistance Center help line listed above for more information. If you determine that you were drinking water contaminated with PFAS compounds at levels beyond regulatory guidelines (70 parts per trillion for combined PFOS and PFOA, though some are acting to make that limit even stricter), contact your local health department, and inform your family physician.

Sources: Michigan PFAS Action Response Team, ATSDR, EPA, New Hampshire Department of Environmental Services. Free Press staff writer Todd Spangler contributed.