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Per- and Polyfluoroalkyl Substances (PFAS)

What are PFAS?  |  Known PFAS Sources
Toxicity and Health Effects  |  PFAS Resources
Connecticut PFAS History  |  PFAS Task Force

What are PFAS?

Per- and polyfluorinated alkyl substances are a group of over 4,000 manmade chemicals, collectively referred to as PFAS, that have recently entered the national spotlight as emerging contaminants with serious adverse impacts on human health, even at low concentrations in the parts per trillion range.

Known PFAS Sources

PFAS have been manufactured and used worldwide since the 1940s. Due to their chemical stability, heat resistance, and ability to repel oil and water, PFAS are used in thousands of consumer products and industrial processes. The known sources of PFAS include:

  • Nonstick cookware
  • Grease-resistant and waterproof coatings on food packaging (e.g., popcorn bags, takeout containers, and fast food wrappers)
  • Coated paper products
  • Waterproof, water-resistant, and stain-resistant textiles (e.g., clothing, shoes, upholstery, and carpets)
  • Cosmetics and personal care products
  • Industrial and household cleaning products
  • Floor, car, and boat waxes
  • Engineered coatings used in semiconductor production
  • Metal plating and finishing
  • Etching of metals, plastics, and glass
  • Plastics, resins, and rubber products
  • Surface coating, paint, varnish, and inks
  • Cable and wire insulation for electronics
  • Aqueous Film-Forming Foam (AFFF) used to extinguish flammable liquid fires
  • Biosolids

PFAS are not naturally found in the environment. However, because these substances are highly mobile in water and air, they spread throughout the environment easily and can contaminate soil, groundwater, and surface water.  Since PFAS are not broken down by natural processes, they persist in the environment indefinitely.

Toxicity and Health Effects

Research on the human health and ecological impacts of PFAS is rapidly evolving.  Some PFAS have been proven to bioaccumulate (accumulate within the body) in animals and humans when ingested.  Certain PFAS have been linked to health risks including developmental effects in fetuses and infants, various forms of cancer, and decreased liver, thyroid, and immune system function.

DPH Drinking Water Section PFAS webpage

EPA PFAS webpage

ATSDR PFAS webpage

PFAS Resources




Other States
Analytic Methods
  • EPA Method 537.1 – drinking water
  • ASTM D7968-17a Standard Test Method for Determination of Polyfluorinated Compounds in Soil by Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS)
  • ASTM D7979-17  Standard Test Method for Determination of Per- and Polyfluoroalkyl Substances in Water, Sludge, Influent, Effluent and Wastewater by Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS)

The Remediation Standard Regulations do not contain numeric cleanup standards for emerging contaminants, but do require remediation using the procedures for Additional Polluting Substances (APS).  APS Criteria for PFAS have been developed and are available for use upon request.

Connecticut PFAS History

  • Final PFAS Action Plan released on November 4, 2019
  • B-17 plane crashed at Bradley International Airport.  AFFF used to extinguish the fire
  • Draft PFAS Action Plan released on October 1, 2019
  • DPH begins to require PFAS testing at new proposed public water supply wells.
  • DEEP begins to perform PFAS testing near Materials Innovation and Recycling Authority (MIRA) landfills.
  • In response to the release of PFAS-containing firefighting foam from a Bradley Airport hangar that ultimately discharged to the Farmington River, DEEP and DPH meet with and educate public officials and residents in Windsor. DEEP is working with the hangar owner to coordinate ongoing testing and cleanup.
  • Dept. of Emergency Services and Public Protection (DESPP) and DEEP issue an AFFF Use Bulletin to educate local fire departments on PFAS, and recommend no further training with AFFF, discontinued use of legacy AFFF, use of modern AFFF only when necessary, and report to DEEP when AFFF is used.
  • DESPP distributes a survey to fire departments to inventory existing AFFF stock.
  • Governor Lamont establishes the Interagency PFAS Task Force to bring the relevant state agencies and entities together to create a comprehensive state strategy for addressing PFAS.
  • Due to the Westchester PFAS detections, DEEP and DPH lead sampling events and coordinate with the local health department to lead public outreach in Greenwich.  Elevated levels of PFAS above the DPH Drinking Water Action Level are detected in one private well.
  • DPH requires 80 large public water systems to perform land use risk assessments evaluating their water supply sources’ vulnerability to PFAS contamination.
  • DEEP and the Department of Emergency Services and Public Protection (DESPP) form a committee to evaluate and select PFAS-free alternatives to AFFF firefighting foam.
  • NY state officials notify DPH of PFAS groundwater contamination in Westchester County, NY, near the Westchester County Airport.
  • DEEP Remediation Division conducts outreach to Remediation Roundtable on PFAS, requesting that PFAS be addressed as a contaminant of concern at sites where warranted based on past site history and operations.

  • DPH establishes a Drinking Water Action Level of 70 ppt for the summed concentrations of five PFAS compounds: perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), perfluoroheptanoic acid (PFHpA), and perfluorohexanesulfonic acid (PFHxS).
  • DEEP and DPH staff begin to collaborate on PFAS.
  • EPA-mandated testing confirms that none of Connecticut’s large public drinking water systems (i.e., systems serving >10,000 people) contain elevated levels of PFAS above EPA reporting limits at that time. 

Contaminants of Emerging Concern

Content last updated June 2, 2020