Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) in Drinking Water

Yes, PFAS are harmful to your health. The lower your exposure to PFAS, the lower your risk of having negative health effects. 

The new proposed Environmental Protection Agency (EPA) levels tell us that health effects might occur at lower levels than the EPA previously thought, and at lower levels than can currently be measured. Health risks depend on the specific chemical you are exposed to, how much of the chemical you are exposed to, for how long, and during which life stage(s) you are exposed. 

Exposure to PFAS may result in a wide range of health problems, including: 

• Developmental effects, including to fetuses after exposure during pregnancy or postnatal development (for example, decreased birth weight, accelerated puberty, skeletal variations, development of the immune system)

• Cancer (for example, testicular, kidney)

• Liver effects 

• Immune effects (for example, decreased antibody response to vaccination, decreased immune response)

• Thyroid effects and other effects (for example, cholesterol changes)

Some populations are especially sensitive to PFOA and PFOS including babies, children who are developing, and people who are pregnant or might become pregnant. 

If you have been exposed to PFAS and are concerned about your health, talk to your health care provider. 

You may be exposed to PFAS in drinking water, food, indoor dust, some consumer products, and workplaces. Drinking contaminated water or eating food that contains PFAS are the most common ways to be exposed to PFAS. PFAS are not easily absorbed through your skin. 

Although some types of PFAS are no longer used, some products may still contain PFAS, including:

• Food packaging materials

• Nonstick cookware

• Furniture, upholstery, and stain-resistant carpets and fabrics

• Water-resistant clothing

• waterproofing sprays

• Cleaning products

• Paints, varnishes, waxes, sealants and adhesives

• Some types of firefighting foam

• Cosmetics

If you are on a public water system, your water has been tested for PFAS. Find PFAS results for your water system

If you are on a private well or spring, the Health Department recommends testing your water for bacteria, inorganic chemicals and gross alpha radiation by using the Vermont Homeowner Testing Package. If you have high levels of contaminants in your drinking water, we recommend treating your water. 

If you’d like to test your water for PFAS, find a certified drinking water lab. Testing for PFAS can be expensive. Oftentimes, the treatment system you install for other common contaminants in Vermont water will also treat for PFAS.

Vermont's health advisory level for the sum of five PFAS is 20 parts per trillion (ppt) in drinking water. The five PFAS chemicals are:

• PFOA

• PFOS

• PFHxS (perfluorohexane sulfonic acid)

• PFHpA (perfluoroheptanoic acid)

• PFNA (perfluorononanoic acid)

If your water has been tested and the total sum of the five PFAS is more than 20 ppt, the Health Department recommends you stop using your water for drinking, food preparation, cooking, brushing teeth, preparing baby formula, or any other way of ingestion. Use bottled water that has been shown to not contain PFAS or water from a known safe source, or install a treatment system to remove PFAS. Do not use water containing the five PFAS over 20 ppt to water your vegetable garden. The PFAS could be taken up by the vegetables.

New proposed EPA regulatory levels

The regulation of PFAS continues to change as new data and information become available. Recently, the EPA proposed regulatory levels (called maximum contaminant levels, or MCLs) for PFOA and PFOS in public drinking water. The proposed MCL for each chemical is 4 ppt. The EPA also proposed a grouped MCL for the sum of four other PFAS: PFBS, PFNA, PFHxS, and GenX. The Health Department will work with the Department of Environmental Conservation to evaluate the new EPA proposals and determine how they will impact Vermont’s current health advisory level for PFAS and how guidance may change.

This treatment advice is only for people who are on private water, meaning you own your well or spring.

The Health Department recommends treating your drinking water if the sum of PFOA, PFOS, PFHxS, PFHpA and PFNA levels is at or above 20 parts per trillion (ppt). 

There are two kinds of systems that treat for PFAS: 

• A single tap/faucet treatment, or point-of-use treatment system, which only treats water for drinking and cooking.

• Whole home treatment, or point-of-entry treatment system, which treats all the water in your home.

Point-of-use treatment is the most cost-effective and simplest treatment solution. The Health Department recommends point-of-use treatment since consuming water with PFAS is more of a health concern than if you use the water to wash your hands, shower, or other means of skin contact.

What to consider before installing a treatment system

• Test your water using the Vermont Homeowners Testing Package before installing a treatment system for PFAS. The results can help indicate which system will work best for your water. Plus, the results will show whether you need to “pretreat” your water for other contaminants (for example, arsenic, uranium or gross alpha) before it can be treated for PFAS.

• Consider the cost of testing, maintaining and replacing components (for example, filters) before deciding on a treatment option. 

For all treatment systems, it is critical that you regularly maintain the system and replace the filters by following the manufacturer’s instructions, or the instructions from a water treatment specialist. If you do not, then the system will fail and PFAS will not be removed from your water as effectively.

Treatment at a single tap (point-of-use treatment, or POU)

A POU treatment system is typically installed under or near your kitchen sink to treat the water you use for drinking or cooking. It’s important to only use water from this tap for cooking, drinking, and making ice and baby formula. 

There are two options for POU treatment systems: reverse osmosis and granular activated carbon.

There are advantages and disadvantages to both treatment options. Consult with a water treatment specialist to help you determine which system makes the most sense given your circumstances and water quality. Both systems lower PFOA and PFOS levels to below 70 ppt (the previous EPA health advisory level). However, research has shown that these systems can lower PFAS – including the five in the Vermont health advisory level – to 2 ppt, which is below what can be detected using current technologies. 

Reverse osmosis (RO)

An RO system is typically installed under the kitchen sink, and the treated water comes out of a separate tap that is near the kitchen faucet. You may need pretreatment (for example, a water softener) since hardness, total dissolved solids, iron and pH can affect how effective the system will be at removing PFAS. Make sure to install an RO system that meets NSF/ANSI Certification 58. Learn more about reverse osmosis systems

Granular activated carbon (GAC)

Depending on the system, a GAC system can be installed under your kitchen sink, connect to your existing faucet, or it can be a “pitcher-style” filter. GAC is known to be most effective at removing PFOA and PFOS, but is less effective at removing other PFAS, like PFBS and PFBA. The effectiveness of GAC systems at removing PFAS depends on how often the filters are changed out, the size of the filter, which PFAS are present, and other water properties (for example, hardness, dissolved solids, and pH). Make sure to install a GAC system that meets NSF/ANSI Certification 53.

It’s important to know that GAC systems alone are not effective at reducing other contaminants that are common in water in Vermont like arsenic, uranium, nitrate, manganese or bacteria. It is especially important to test for radioactive elements that are in your water before you install a GAC system. This is because GAC can remove and concentrate radon and could create a radiation hazard. GAC is not recommended to treat water with radon levels above 10,000 picocuries per liter (piC/L). If your water contains contaminants not removed by GAC, you may need to install other treatment systems before installing a GAC system to treat for PFAS. Learn about testing your water

Whole home treatment (point-of-entry treatment)

Whole-home treatment is only necessary if there is someone in your home (for example, a young child) who is likely to drink water from taps other than the tap where treatment is installed, or if you need to “pretreat” your water for other contaminants (for example, iron, manganese, hardness, taste and odor, or radon) before you treat for PFAS.

If you’d like to treat all of the water that comes into your home, a multistage carbon-based point-of-entry treatment (POET) system is best. During the PFOA response in Southern Vermont in 2016, the State used a specific type of POET system, which other New England states have also used. It has proven to be effective at removing PFAS to non-detectable levels. This treatment system is not generally sold as a single off-the-shelf product. You will need to contact a certified water treatment specialist who will be able to design and build the system. The specialist will also tell you how to maintain the system and how often to change the filters. The treatment system uses these components:

• Five-micron particulate (sediment) filter for pre-filtering

• A softener to reduce water hardness, iron, and manganese

• Two granular activated carbon (GAC) treatment vessels (about two cubic feet each) in series with a test port installed after the lead treatment unit (the exact size and number of GAC vessels required depends on flow rate and flow volume associated with the home)

• Five-micron particulate filter for post-filtering

• Totalizer (flow) meter 

• Ultraviolet (UV) disinfection bulb 

• Connection to the household plumbing 

Note that because this system uses GAC filters, it is not effective at reducing contaminants that can be found in water in Vermont like arsenic, uranium, nitrate or manganese. It is especially important to test for radioactive elements before you install this system. This is because GAC can remove and concentrate radon and could create a radiation hazard. GAC is not recommended to treat water with radon levels above 10,000 picocuries per liter (piC/L). If your water contains contaminants not removed by GAC, you may need to install other treatment systems before installing a GAC system to treat for PFAS. Learn about testing your water