PFAS: Per- & Polyfluoroalkyl Substances

Per- and polyfluoroalkyl substances (PFAS) are manufactured chemicals used in many household products including nonstick cookware (e.g., Teflon™), stain repellants (e.g., Scotchgard™), and waterproofing (e.g., GORE-TEX™).  They are also used in industrial applications such as in firefighting foams and electronics production.

There are thousands of PFAS chemicals, and they persist in the environment. Two well-known PFAS chemicals are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS).  These were phased out of production in the United States and replaced thousands of other PFAS chemicals including hexafluoropropylene oxide-dimer acid (commonly known as GenX), perfluorobutane sulfonic acid (PFBS) and others.  Additional information on PFAS from the United States Environmental Protection Agency (U.S. EPA) can be found at epa.gov/pfas.

It is important to note that a person’s exposure to these PFAS can vary due to several factors because they have been used in millions of ways since the 1940s; Teflon-coated pans being the first consumer use back in 1961.  The EPA itself estimates that only 20% of a person’s exposure to PFAS comes from drinking water.

While exposure through drinking water is a concern, 80% of a person’s PFAS exposure can come from consumer products such as cookware, cosmetics, food wrappings, stain/water-resistant clothing, carpet and furniture treatments, and even deodorants, contact lenses, dental floss, and toilet paper.  People can also be exposed by eating foods that may contain PFAS, such as fish, and it has been found in the air and in rainwater.

PFAS date back to the 1940s when these chemicals were first used in industrial and commercial applications due to their remarkable resistance to heat and water. After it was discovered that they could be used to improve consumer products and were allowed to be discharged into waterways, PFAS became prevalent in the environment, including air, water sources, soil, and even wildlife.

Over time, concerns have emerged about the potential health impacts of PFAS, prompting regulatory scrutiny and efforts to reduce their adverse effects on human health and the environment.

The Safe Drinking Water Act (SDWA) empowers the EPA to establish legal limits for specific contaminants in drinking water. On April 10th, 2024, the EPA introduced national drinking water standards for PFOA and PFOS, two PFAS chemicals, with additional regulations proposed for PFNA, PFHxS, PFBS, and GenX. (below) More information on these standards can be found on the EPA's website. 

The new standards, which do not take effect until 2031, are as follows:

• Four parts per trillion (4 ppt) for perfluorooctanoic acid (PFOA)
• Four parts per trillion (4 ppt) for perfluorooctane sulfonate (PFOS)
• Ten parts per trillion (10 ppt) for perfluorononanoic acid (PFNA)
• Ten parts per trillion (10 ppt) for perfluorohexane sulfonate (PFHxS)
• Ten parts per trillion (10 ppt) for hexafluoropropylene oxide dimer acid (HFPO-DA, also known as GenX).

There is also a Hazard Index for a mixture of at least of two of the following PFAS:  PFNA, PFHxS, HFPO-DA, and perfluorobutane sulfonate (PFBS) with a total of 1.  (This is not parts per trillion, billion, or million.  It’s a sum of the factions of levels found for each compound.)*

*Note the Hazard Index standards are still under review by EPA.

Yes, you can still drink tap water and use it for cooking and bathing.  The EPA does not recommend bottled water solely based on PFAS concentrations in Wilmington's water.  Bottled water may have higher PFAS levels and is less regulated than tap water.  We understand if some customers decide to make the personal choice to use water filters.  Certified water filtration systems may lower levels of some PFAS if the filter is properly maintained. 

More information on certified filters is available on the National Sanitation Foundation's website.

The City of Wilmington sampled for PFAS in 2022 to get an understanding of the levels in the drinking water leaving the treatment plants.

In 2023, the City of Wilmington tested our drinking water for 29 PFAS through its compliance with U.S. EPA Unregulated Contaminant Monitoring Rule, or UCMR. Through the UCMR process, water systems collect data on a group of contaminants that are currently not regulated in drinking water at the federal level.  U.S. EPA then uses this information when deciding if it needs to create new drinking water limits. More information on UMCR 5 can be found on the EPA website.

While the new standards do not take effect for another five years, the City of Wilmington understands our customers may be concerned, so we are providing this information about the EPA’s process, the results found in our drinking water, and the steps we are taking to address the issue.

While our overall PFAS levels are low, our 2022 testing for PFOA found a level slightly over the EPA’s proposed drinking water standard.  As a result, we are taking the following proactive actions:

• We are voluntarily testing our water (monthly) to gather the best data possible to guide future decision-making and keep our customers informed.  We will also participate in all required Federal and State testing.
• We will continue to coordinate and collaborate with State and Federal regulatory agencies regarding ongoing research and rule-making developments.
• We have chosen to take part in legal action that seeks to compensate Wilmington for our PFAS-related efforts.
• We will continue openly communicating about PFAS, and we encourage our customers to contact us with any questions.
• We are also examining strategies to effectively address PFAS compounds through our water treatment process.

Regardless of the challenges posed by PFAS, the City of Wilmington is committed to providing safe, reliable drinking water.  For more information about the quality of your water, you can read our annual Water Quality Reports.

The City of Wilmington sampled for PFAS in 2022 to get an understanding of the levels in the drinking water leaving the treatment plants.  The results are provided in the table below.

In 2023, the City of Wilmington tested our drinking water for 29 PFAS through its compliance with U.S. EPA Unregulated Contaminant Monitoring Rule, or UCMR. Through the UCMR process, water systems collect data on a group of contaminants that are currently not regulated in drinking water at the federal level.  U.S. EPA then uses this information when deciding if it needs to create new drinking water limits.  The results of our UMCR 5 are provided in the table below, and more information can be found on the EPA's UCMR Data Finder.

Note that PFAS chemicals are unique, so two PFAS chemicals at the same level typically do not present the same risk. Therefore, you should not compare the results for one PFAS chemical against the results of another. For more water quality information, read our Water Quality Reports.

2022 PFAS Data

Results listed in parts-per-trillion (ppt)

2023 PFAS Data

Results listed in parts-per-trillion (ppt)

2024 PFAS Data

Results listed in parts-per-trillion (ppt)

To reduce overall exposure to PFAS, consider your daily product choices. PFAS are commonly found in heat, stain, or water-resistant items such as clothing, cookware, cosmetics, and treatments for carpets and furniture. They're also present in personal care products like dental floss, toilet paper, contact lenses, feminine products, and deodorants.

Choosing PFAS-free alternatives can help lower exposure, although it may be challenging given the pervasive nature of PFAS in various products, including fertilizers and compost. A list of potentially PFAS-containing product types is available on the Agency for Toxic Substances and Disease Registry website.

A good first step is to increase your understanding of how PFAS can enter our bodies, our homes, and the environment.  Ongoing education on PFAS and staying informed on federal and state guidance can help manage personal exposure.

Another key action is to purchase products with less or no PFAS.  Many companies are working to remove PFAS from their products.  Buying PFAS-free options will help decrease the amount of new PFAS entering the environment, and reward companies who have committed to removing PFAS from their manufacturing processes.