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Ann Arbor PFAS Information

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​​​​​What are Per- and polyfluoroalkyl substances (PFAS)?

Per- and polyfluoroalkyl substances (PFAS), 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. PFAS have been around since the 1950s, but we didn’t know a lot about their effects until the early 2000s, when scientists began releasing data on PFAS health impacts and their persistence in the environment. For decades, they have been used in many industrial applications and consumer products such as carpeting, waterproof clothing, upholstery, food paper wrappings, fire-fighting foams, and metal plating. They are still used today. PFAS have been found at low levels both in the environment and in blood samples of the general U.S. population. These PFAS 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. 

What is PFOS? What is PFOA?

PFOS and PFOA stand for perfluorooctane sulfonate and perfluorooctanoic acid, respectively. Both are fluor​inated organic chemicals, part of a larger family of compounds referred to as perfluoroalkyl substances (PFAS). 

Are there PFAS in Ann Arbor’s Drinking Water?

The Michigan Department of Environmental Quality (DEQ) has released data from the ​latest round of finished drinking water PFAS testing. Those results show that Ann Arbor drinking water remains significantly below the Health Advisory Level established by Environmental Protection Agency (EPA) and adopted by the State of Michigan. The City continues to monitor for PFAS compounds and remains committed to providing safe drinking water that complies or exceeds all regulatory guidelines.

PFAS, or per- and polyfluoroalkyl substances, have been found in drinking water supplies around the country due to their ubiquitous use in everyday products and their long decay time. The EPA has established a health advisory level of 70 parts per trillion (ppt) for two particular PFAS, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA).​

Test re​sults received from DEQ indicate that PFOS/PFOA levels in the City's drinking water are 4 ppt, well below the current health advisory level of 70 ppt. PFOS/PFOA represent the two PFAS with the most health data available. Because analytical techniques are now available to test other PFAS compounds, the State of Michigan also tested for an additional 22 PFAS chemicals. Researchers are studying potential health impacts of several PFAS, but limited health impact data is available for these additional chemicals. However, the State is taking a conservative approach and totalizing the concentration for all 24 PFAS chemicals. The City's total concentration for all 24 chemicals reported by the State is 39 ppt. Since there is no health advisory for these additional PFAS chemicals, it is currently not possible to compare the total concentrations of the 24 chemicals measured to an acceptable health level. 

What is Ann Arbor doing to remove PFAS from drinking water?

Currently, granular activated carbon (GAC) filtration is the best available technology for removing PFAS in drinking water. The City has GAC filters, and has been piloting a new type of carbon in several of its filters since November 2017. This new carbon has demonstrated enhanced removal of PFAS. Due to this success, City staff will present a plan to City Council in September to propose replacing all of the older carbon in the City's filters with the new type of carbon. It is estimated that the additional cost to replace the GAC in the filters will be $850,000 in fiscal year 2019.  ​

In addition, the ​City continues to voluntarily test for PFAS chemicals in the drinking water on a monthly basis. There are several initiatives occurring in the State of Michigan to investigate sources of these chemicals. The MDEQ issued a news release on May 18, 2018 describing some of these initiatives.

One initiative is that MDEQ will be sampling all public water supplies in the State of Michigan by the end of 2018 for PFAS. Since the City of Ann Arbor has already been sampling for these chemicals, this program will have little impact on the City. A second initiative that will impact the City is MDEQ’s plan to sample water from the Huron River at several locations upstream of the City’s drinking water intake at Barton Pond. The purpose of this effort is to attempt to identify the source of PFAS compounds in the river. Sampling took place on July 24, 2018 and the results should be available soon. Because these compounds can be difficult to remove from water, eliminating the source (if possible) is typically more cost effective than treatment. 

Will Ann Arbor test residential tap water for PFAS?

The City currently sends samples of the finished drinking water to be measured for PFAS once a month, and the data are provided in the City’s Annual Water Quality Report. PFAS are not reactive, and concentrations in a homeowner’s tap water will be the same as the concentration leaving the Drinking Water Treatment Plant. 

Because the PFAS concentration does not change between the plant and a homeowner’s tap, the City will not pay to test individual homeowner’s tap water for PFAS. The City sends its samples to a commercial lab for PFAS analysis because it does not have the capability to measure PFAS on site. Analysis for PFAS requires specialized equipment, and the method is very complex. ​

Is there a risk to swimming or bathing in water with PFAS?

You may bathe and swim in water containing PFAS. PFAS do not easily absorb into the skin. It is safe to bathe, as well as do your laundry and household cleaning. It is also safe to swim in and use recreationally. Getting water with PFAS on your skin will not harm you.

What about recent reports of PFAS in fish and foam from the Huron River? 

The Michigan Department of Health and Human Services (MDHHS) has issued an expanded ‘Do Not Eat’ fish advisory for all fish in the Huron River in Livingston, Oakland, Washtenaw, Wayne, and Monroe Counties. ​

The ‘Do Not Eat’ advisory for the Huron River starts where N. Wixom Road crosses in Oaklan​d County and extends downstream to the mouth of the Huron River as it enters Lake Erie in Wayne County. This includes: 

  • Norton Creek (Oakland County) 
  • Hubbell Pond, also known as Mill Pond (Oakland County) 
  • Kent Lake (Oakland County) 
  • Ore Lake (Livingston County) 
  • Strawberry & Zukey Lake (Livingston County) 
  • Gallagher Lake (Livingston County) 
  • Loon Lake (Livingston County) 
  • Whitewood Lakes (Livingston County) 
  • Base Line & Portage Lakes (Livingston/Washtenaw County line) 
  • Barton Pond (Washtenaw County) 
  • Geddes Pond (Washtenaw County) 
  • Argo Pond (Washtenaw County) 
  • Ford Lake (Washtenaw County) 
  • Bellville Lake (Wayne County) 

This extension is a result of new perfluorooctane sulfonate (PFOS) fish data from the Michigan Department of Environmental Quality. Base Line Lake and Argo Pond fish fillet data, downsteam from Kent Lake, were found to have high PFOS levels. Additionally, high PFOS surface water levels were found upstream of Kent Lake. 

Touching the fish or water and swimming in these water bodies is not considered a health concern as PFAS do not move easily through the skin. An occasional swallow of river or lake water is also not considered a health concern.

For current guidelines relating to PFAS fish contamination, visit Michigan.gov/pfasresponse. For more information about the Eat Safe Fish guidelines, visit Michigan.gov/eatsafefish​


In addition, the health department reminds users to avoid swa​llowing foam on the river. It noted:

"It is recommended that visitors to the Huron River avoid swallowing foam on the water during recreational activities, though an accidental swallow of water is not considered a health concern. Residents are also encouraged to wash their hands after touching foam to avoid swallowing PFAS that might be on your hands. Skin contact with the foam or water is not considered a health concern because current science indicates that PFAS do not move easily through the skin.

Additionally, the Michigan Department of Agriculture and Rural Development recommends that people not allow their pets – especially dogs – to come into contact with or swallow the foam. Dogs can potentially swallow foam collected in their fur when grooming themselves. Dogs should be thoroughly rinsed off with fresh water after contact with foamy water."

Does the City's Fire Department use firefighting foam with PFAS in it?

In the past, like many fire departments, the Ann Arbor Fire Department (AAFD) maintained a stock of firefighting foam that contained PFAS chemicals and was used for fighting flammable liquid fires such as gasoline, oil and other hydrocarbons.

In the fall of 2018, the AA FD agreed to immediately halt use of this type of foam for traini​ng purposes and to seek alternative options for fighting such fires. In October of 2018, the AAFD purchased foam that is free of PFAS. The old foam was disposed of properly via a regulated waste disposal company.​​

How can PFAS affect people’s health?

Some scientific studies suggest that certain PFAS may affect different systems in the body. Although more research is needed, some studies have linked higher levels of PFAS in people’s blood to health impacts such as:

  • affect growth, learning, and behavior of infants and older children
  • lower a woman’s chance of getting pregnant
  • interfere with the body’s natural hormones
  • increase cholesterol levels
  • affect the immune system and
  • increase the risk of certain types of cancer

At this time, scientists are still learning about the health effects of exposures to mixtures of PFAS. ​If you are concerned about exposure to PFAS in your drinking water, please contact the Ann Arbor Water Treatment Plant at 734.994.2840 or consult the City’s Annual Water Quality Report.

Additional information

To learn more about PFAS and what you can do to prevent being exposed or using products with PFAS, here a few good resources: 


​919 Sunset Road
Ann Arbor, MI 48103
Phone: 734.794.6426​