Per- and Polyfluoroalkyl Substances (PFAS) in Private Well Drinking Water Supplies

What you need to know about the possibility of PFAS in your well water

INTRODUCTION

This page provides answers to questions frequently asked by private well owners about per- and polyfluoroalkyl substances (PFAS) in a private drinking water supply. A separate VDH page, “Per- and Polyfluoroalkyl Substances (PFAS)”, describes the sources of PFAS compounds, health effects, and VDH recommendations to reduce consumer exposure.

WHAT ARE PFAS?

Per- and polyfluoroalkyl substances (PFAS) are a group of human-made chemicals that were created for a variety of household and industrial uses. PFAS can repel oil, grease, and water, so they have been used in protective coatings for many different products including food packaging, nonstick cookware, carpets and upholstery (stain-protectants), mattresses and clothing (water-proofing), and have also been used in fire-fighting foams. Some of the more commonly known PFAS are perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). GenX chemicals are considered a replacement for PFOA and PFBS is considered a replacement for PFOS.

WHAT ARE LEVELS OF CONCERN FOR PFAS CHEMICALS?

EPA HEALTH ADVISORIES FOR PFAS

On June 15, 2022, EPA released four drinking water health advisories for PFAS contaminants. These health advisories are:

  • Interim updated Health Advisory for PFOA = 0.004 nanograms per liter (ng/L), or parts per trillion (ppt)
  • Interim updated Health Advisory for PFOS = 0.02 ng/L
  • Final Health Advisory for GenX chemicals = 10 ng/L
  • Final Health Advisory for PFBS = 2,000 ng/L

Drinking water health advisories provide information on contaminants that can cause human health effects and are known or anticipated to occur in drinking water. EPA’s health advisories are non-enforceable and non-regulatory and provide technical information to states agencies and other public health officials on health effects, analytical methods, and treatment technologies associated with drinking water contamination. EPA’s lifetime health advisories identify levels to protect all people, including sensitive populations and life stages, from adverse health effects resulting from exposure throughout their lives to these PFAS in drinking water.

EPA is currently developing Maximum Contaminant Levels (MCL) for some PFAS, which will apply to drinking water supplies falling under the Safe Drinking Water Act.  Until such time as MCLs are published, VDH is working to review the new EPA Interim Health Advisories and will determine next steps based upon that review.

For more information about EPA Health Advisories for PFAS see Drinking Water Health Advisories for PFAS Fact Sheet for Communities and Questions and Answers: Drinking Water Health Advisories for PFOA, PFOS, GenX, PFBS FAQs.

 ATSDR MINIMAL RISK LEVELS

The Center for Disease Control and Communication (CDC) Agency for Toxic Substances and Disease Registry (ATSDR) developed the PFAS Exposure Assessment Technical Tools (PEATT) to help State, local, tribal, and territorial health departments conduct PFAS biomonitoring activities, with the assumption that drinking water is the primary source of PFAS exposure. The PEATT includes a protocol for statistically-based representative sampling, risk communication materials, questionnaires, and EPA’s water sampling protocol to help characterize PFAS exposure in communities.

ATSDR Minimal Risk Levels (MRLs) are screening levels. ATSDR uses them to identify environmental exposures that might harm people’s health. If an exposure is below an MRL, it is not expected to result in adverse health effects. If an exposure is above an MRL, ATSDR conducts further evaluation to determine if the exposure might harm human health. ATSDR sets each MRL below a value that is likely to cause a health effect. ATSDR develops MRLs using data from the epidemiologic and toxicologic literature. When the scientific data on a hazardous substance is incomplete, ATSDR applies uncertainty factors as part of the MRL calculation. These uncertainty factors help ensure that MRLs are at a level where health effects in people are not expected by accounting for incomplete information about the chemical levels that may be associated with health  effects, and other variables.

Pending EPA determination of PFAS MCL(s), VDH recommends that well owners consider comparing test results of well water to the ASTDR (PEATT) MRLs.

PFAS Chemical Adult Child
PFOA 78 ppt 21 ppt
PFOS 52 ppt 14 ppt
PFHxS 517 ppt 140 ppt
PFNA 78 ppt 21 ppt

HOW DO PFAS GET INTO PRIVATE WELL WATER SUPPLIES?

While consumer products and food can be sources of exposure to PFAS, private drinking water can be a significant source of exposure at locations where these chemicals have contaminated water supplies. Such contamination is often localized and associated with a specific facility; for example, an airfield where PFAS were used for firefighting or a facility where these chemicals were produced or used.

PFAS TESTING OF PRIVATE WELLS

VDH does not have a program for the sampling and testing of water quality in private wells, nor the authority to require ongoing sampling and testing of private wells. Sampling of private wells by well owners is voluntary.

SHOULD I TEST MY PRIVATE WELL FOR PFAS?

VDH recommends that private drinking water wells be tested for PFAS contamination, especially if your well is located within one to two miles of a known source of PFAS or of other water supplies where PFAS has been detected. Sources of PFAS may include airfields where certain firefighting foams were used in the past, firefighting training areas, certain manufacturing facilities, and some waste disposal sites. Your local health department may have information on historical or potential sources of PFAS, or other PFAS impacted water supplies, that may be in proximity to your private well. Because PFAS have been widely used in consumer products, it is possible that some septic systems and landfills may also be a source of PFAS in groundwater.

HOW CAN I TEST MY WELL WATER FOR PFAS?

Currently, there are three U.S. EPA testing methodologies for testing drinking water for PFAS. Commercial laboratories will analyze drinking water for PFAS using either USEPA Method 537, 537.1, or 533. These methods test for multiple PFAS compounds.

Use the Laboratories Approved by EPA to Support UCMR5 list to find laboratories that have been certified by EPA to test for PFAS in drinking water. Note: this list is subject to update and there may be other laboratories able to test for PFAS.

When collecting the water sample, VDH encourages well owners to avoid cross-contamination by carefully following the PFAS sample collection procedures or those provided by the laboratory that will be doing the analysis.

HOW OFTEN SHOULD I TEST MY WELL WATER FOR PFAS?

If the initial testing does not detect PFAS, VDH does not recommend additional testing unless one or more of the following conditions apply:

  • EPA releases MCLs for one or more PFAS.
  • A release of PFAS is documented within 2 miles of your well intake, especially if your well is downhill or downstream of the source of release.
  • Well owners in your area are advised by EPA, VDH, another state agency, or your local government to consider testing your well water.

CAN I USE A POINT OF USE (POU) OR A POINT OF ENTRY (POE) WATER TREATMENT DEVICE TO REMOVE PFAS?

Point of Use (POU) water treatment devices treat the water at one fixture in a home, such as a kitchen faucet.  Point of Entry (POE) water treatment devices treat all of the water for the main water line serving a whole house.

  • Yes, you may use a POU or POE treatment device to remove PFAS. However, before installing any treatment device for drinking water, you should get your water tested, because the type of treatment device you select will depend on the level of specific PFAS in the water. You should also test your water after the treatment device is installed to verify that it is removing PFAS to levels less than 20 ppt for the sum of PFAS.
  • Ingestion of water with elevated PFAS is the main health concern, rather than other uses such as showering or use of the water for laundry. Therefore, installing a POU treatment device for drinking or food preparation in the kitchen, e.g., under a kitchen sink, may be a good option and location for a treatment device.

Although POU and POE treatment devices are not specifically designed to meet EPA Health Advisories for PFAS, there are systems that have been designed to reduce the sum of PFOS and PFOA to below EPA’s former Health Advisory of 70 ng/L. Any treatment device you use should be certified to meet the National Sanitation Foundation (NSF) standards to remove PFOS and PFOA compounds so that the sum of their concentrations is below 70 ng/L.  If you choose to install a treatment device, to verify that the device achieves PFAS levels at or below ATSDR MCLs, you may need to resample your water after the treatment device has been installed.

Additional Resources: EPA Researchers Investigate the Effectiveness of Point‐of‐use/Point‐of‐entry Systems to Remove Per‐ and Polyfluoroalkyl Substances from Drinking Water

CAN I USE BOTTLED WATER IF I HAVE CONCERNS ABOUT PFAS IN MY PRIVATE WELL WATER?

VDH does not advocate use of bottled water when PFAS is identified in a private well because it is possible that bottled water itself may contain PFAS. If PFAS has been detected in your private well and consumers include one of the groups considered most sensitive to PFAS (pregnant women, nursing mothers, and infants) it may be possible to minimize exposure by using bottled water that has been tested for PFAS for drinking, making infant formula, and cooking of foods that absorb water. VDH does not maintain records of bottled water suppliers who have tested for PFAS; you will need to contact the bottled water supplier to determine whether a given the bottled water source will be a reliable alternative to your well water.

WHERE CAN I GET MORE INFORMATION ON PFAS?

PFAS are a topic of current research by public health agencies.  You can get more information at the following pages: