PFAS Testing Results, Current & Proposed Regulations

History of PFAS Testing in Grand Rapids

As part of the Unregulated Contaminate Monitoring Rule, we tested for PFAS-related compounds on four occasions in 2014, 2015, and 2017, and the results were non-detect. In 2018, and with improved test methods, our test results mirrored testing conducted by the state.

In April of 2019, the State of Michigan began a statewide sampling program and sampled all the surface water systems in the state for six consecutive months. Our test results showed that our tap water concentration of PFOS and PFOA are well below the USEPA lifetime health advisory of 70 part per trillion (ppt) established by the U.S. Environmental Protection Agency and the Department of Environment, Great Lakes, and Energy (EGLE) as well as regulatory limits being discussed. See table below for our PFAS testing results.


What are the differences in results between the EPA Method 537 & Isotope Dilution Method?

PFAS testing is in its infancy, and we are limited in what the laboratory equipment is able to detect. As testing methods continue to be developed, the reporting limits of these tests have improved. In previous testing using the EPA Method 537, the detection limits were in the 20 ppt to 30 ppt range. Detection limits are now as low as 2 ppt. As laboratories improve methods to better detect these compounds, we will continue to monitor our results and publish them.


Current and Proposed PFAS Regulation in Drinking Water

Currently, there is no regulatory drinking water standard for PFAS chemicals. In May 2016, the USEPA established a non-regulatory lifetime health advisory (LHA) for two of these chemicals; PFOS and PFOA. The LHA for PFOS and PFOA is 70 ppt combined, or individually if only one of the chemical is present. The State of Michigan has adopted the 70 ppt combined limit as well. There are other states and regulatory institutions that are recommending lower limits. We welcome this proactive approach sharing commitment to our community’s health. The State of Michigan is currently working on new lower limits.  Below are the current and proposed regulations.

Current State Regulations Agency for Toxic Substances Disease Registry Report (proposed)

PFOS (Perfluorooctane sulfonic acid)

 70 ppt  7 ppt

PFNA (Perfluorononanoic acid)

 N/A  10.5 ppt

PFOA (Perfluorooctanoic acid)

 70 ppt  11 ppt
PFHxS (Perfluorohexane sulfonic acid)  N/A  70 ppt

1 parts per trillion (ppt) is equal to 1 drop of water in 18 million gallons of water


PFAS Testing Results and Next Steps

We recently sampled the City water system’s Lake Michigan source water and tap water to parallel similar testing the Michigan Department of Environment, Great Lakes, and Energy (EGLE) is conducting across the state. Our test results showed that our tap water concentration of PFOS and PFOA are well below the USEPA lifetime health advisory of 70 part per trillion (ppt) established by the U.S. Environmental Protection Agency and EGLE as well as regulatory limits being discussed. See table below of our PFAS testing results.

Our test results showed what was expected: PFAS-related compounds have been in use around Lake Michigan for decades and a very small amount is present. We expect PFAS levels to remain relatively consistent since Lake Michigan is a stable source of water. We will continue to aggressively sample and test our water in accordance with state regulatory requirements and release our results. We also will continue to use the best available methods and technology in our water testing.

 Sampling Date Raw Water or Treated Drinking Water?  Method PFOS  PFOA 6:2 Fluorotelomer Sulfonates  Compounds Tested
 April 2018 Treated Drinking Water EPA 537 ND 2 NA 14 compounds
  Raw Water Isotope Dilution ND 2 ND 24 compounds
  Treated Drinking Water Isotope Dilution ND ND  3 24 compounds
 June 2018 Treated Drinking Water EPA 537   ND   ND  NA 14 compounds
  Raw Water Isotope Dilution   1.40 ppt 1.09 ppt ND 24 compounds
  Treated Drinking Water Isotope Dilution 1.81 ppt 1.38 ppt 1.55 ppt 24 compounds
 April 2019 Treated Drinking Water EPA 537 ND ND NA 14 compounds
  Raw Water Isotope Dilution ND ND 4 ppt 24 compounds
  Treated Drinking Water Isotope Dilution ND ND 6 ppt 24 compounds
 May 2019 Raw Water Isotope Dilution ND ND ND 24 compounds
  Treated Drinking Water EPA 537 ND ND ND 14 compounds
 June 2019 Raw Water  Isotope Dilution ND ND ND  24 compounds
Treated Drinking Water EPA 537 ND ND NA 14 compounds
 July 209 Raw Water Isotope Dilution ND ND ND 24 compounds
  Treated Drinking Water EPA 537 ND ND NA 14 compounds
 August 2019 Raw Water  Isotope Dilution ND  ND  ND 24 compounds
   Treated Drinking Water  EPA 537 2 ppt ND ND 14 compounds
September 2019 Raw Water Isotope Dilution ND ND ND 24 compounds
  Treated Drinking Water EPA 537 ND ND N/A 14 compounds
December 2019 Raw Water Isotope Dilution ND  ND ND 24 compounds
  Treated Drinking Water EPA 537 2 ppt ND N/A 14 compounds
January 2020 Raw Water Isotope Dilution  ND ND ND 24 compounds
  Treated Drinking Water  EPA 537  ND  ND  N/A 14 compounds
 February 2020 Raw Water  Isotope Dilution ND 2.6 ppt ND 24 compounds
  Treated Drinking Water EPA 537  2.14 ppt  ND N/A 14 compounds
 March 2020  Raw Water Isotope Dilution  ND 2.56 ppt  2.28 ppt 24 compounds
   Treated Drinking Water EPA 537  2.41 ND N/A 14 compounds
 April 2020  Raw Water  Isotope Dilution ND  ND ND  24 compounds
   Treated Drinking Water EPA 537 2.17   ND  N/A  14 compounds
 May 2020 Raw Water  Isotope Dilution  ND  ND  ND  24 compounds
  Treated Drinking Water EPA 537  NA  ND  N/A  14 compounds
June 2020 Raw Water Isotope Dilution ND  2.34  ND  24 compounds
  Treated Drinking Water EPA 537  2.23  ND  N/A  14 compounds
 July 2020 Raw Water Isotope Dulution  ND  ND  ND  24 compounds
  Treated Drinking Water EPA 537  2.37  ND  N/A  14 compounds
 August 2020  Raw Water  Isotope Dilution  ND ND ND  24 compounds
   Treated Drinking Water  EPA 537  2.19  ND N/A  14 compounds
November 2020  Raw Water Isotope Dilution ND ND ND 24 compounds
   Treated Drinking Water EPA 537 ND ND N/A 14 compounds
 March 2021 Raw Water Isotope Dilution ND ND ND  24 compounds
   Treated Drinking Water EPA 537  ND ND N/A 14 compounds
 July 2021  Raw Water Isotope Dilution  ND  ND  ND  24 compounds
   Treated Drinking Water EPA 537 ND ND N/A  14 compounds
September 2021  Raw Water Isotope Dilution ND ND ND  24 compounds
   Treated Drinking Water  EPA 537  ND ND N/A  14 compounds

Note: ND= Not-Detected NA=Not Applicable, compound is not analyzed in the EPA 537 method.

One ppt is equal to 1 drop of water in 18 million gallons of water. The reporting limit for EGLE testing is 2ppt. This provides explanation as to why we have inconsistent detectable vs. non-detectable values in each test. All other results are non-detected unless noted.

If you have any questions about our results, testing or anything related to your water, please contact 311 or (616) 456-3000.

For more on PFAS compounds, tests and other information, visit the State of Michigan’s PFAS Response Team.