(PFAS) Perfluoroalkyl Substances 

Please watch the video below for an update on the hexavalent chromium and PFAS piloting work.

The Town of Shrewsbury participated in a voluntary testing program specifically for this contaminant with the State Department of Environmental Protection in the summer of 2019 along with 21 other communities in the Commonwealth. PFA Image


Through two recent rounds of testing at the Shrewsbury Home Farm Water Treatment Plant we have detected Per-and polyfluoroalkyl substances, also known as PFAS (pronounced P Foss), in our finished blend water (from multiple well sources). The tests show an average total of 13.56 parts per trillion (ppt) in the finished drinking water. 

PFAS is not currently regulated by DEP or EPA. In 2018, the Massachusetts Department of Environmental Protection (DEP) issued a more stringent drinking water guideline of 70 parts per trillion for five combined PFAS compounds. DEP's Office of Research and Standards Guideline currently recommends consumers in sensitive subgroups (pregnant women, nursing mothers and infants) not consume water with PFAS levels about 70 ppt. However, in January 2019 DEP announced they would study and likely set a standard maximum contaminant limit (MCL) for PFAS for drinking water providers.  In June they established 20 ppt as their planned MCL. The Town of Shrewsbury's PFAS level is much lower with an average contaminant level of 13.56 parts per trillion (ppt).

Next Steps 

PFAS can be removed from drinking water through filtration, which would have to be added to the Town's water treatment system. The Town has tested each well individually to determine the level of PFAS in our sources and the feasibility of filtering an individual source well versus the entire system. If possible, this could reduce both construction and ongoing maintenance costs.  

The Town will continue to work closely with MassDEP and will keep the community updated. Additionally, Town staff have already visited several communities that are actively removing PFAS from their water supplies. We will utilize funding approved by Article 3 of the the October 21, 2019 Special Town Meeting, to pilot filtration methods and prudently implement a permanent solution. 

Additional Information

What are PFAS? 

Per-and polyfluoroalkyl substances, also known as PFAS, are a group of manmade chemicals that have been manufactured and used in a variety of industries since the 1950s. They are referred to as ‘forever chemicals’ – they are persistent in our bodies and the environment and many will not naturally degrade. PFAS chemicals are most often commercially used to create grease, water and stain resistant barriers for materials, including Teflon, grease-resistant take out containers, and upholstery and carpet treatments; these chemicals are also found in firefighting foam. 

Why are PFAS only recently garnering attention if they have been used since the 1950s? 

In 2016, the United States Environmental Protection Agency published a drinking water Health Advisory level for two PFAS compounds at a combined 70 parts per trillion as the science to test and identify these chemicals has evolved. In 2018, the Massachusetts Department of Environmental Protection (DEP) issued a more stringent drinking water guideline of 70 parts per trillion for five combined PFAS compounds.  

As of April 2019, DEP has proposed amendments to drinking water guidelines, and groundwater and soil cleanup standards to change the limits to 20 parts per trillion for a combined six PFAS compounds. They are currently soliciting stakeholder input and public comment on all proposed regulations.  


Shrewsbury PFAS in Drinking Water Supply October 17, 2019

Mass DEP Fact Sheet - Per- and Polyfluoroalkyl Substances (PFAS) in Drinking Water: Questions and Answers for Consumers

Massachusetts Department of Public Health- Per- and Polyfluoroalkyl Substances (PFAS) in Drinking Water

Links to additional information

Mass DEP information about PFAS

US EPA information about PFAS

CDC ATSDR information about PFAS

Association of State Drinking Water Administrators PFAS webpage includes information about what other States are doing