PFAS Awareness

Most frequent questions and answers

PFAS is an acronym that describes an extensive list of man-made chemicals that consist of a long chain of carbon and fluorine atoms.

PFAS stands for per and polyfluoroalkyl substances and represents a group of chemicals estimated to contain over 5,000 individual formulations. PFAS are used in many applications because of their unique physical properties that include resistance to high and low temperatures, resistance to degradation, and nonstick characteristics. The resistance to degradation is why PFAS have often been referred to as “forever chemicals”.

PFAS compounds have been widely used in manufacturing many consumer goods, non-stick coatings, carpets, textiles, firefighting foams, cosmetics and various industrial processes. Although there are thousands of PFAS compounds, the EPA has prioritized research on a small number of these compounds that may have health effects at very low concentrations. Two of these are Perfluorooctanoic acid (PFOA) and Perfluorooctane Sulfonate (PFOS).

For the most part, PFOA and PFOS were voluntarily phased out of production in the mid-2000s by manufacturers. However, PFOA and PFOS can still be imported to the U.S. in consumer goods and manufacturers have developed numerous other PFAS chemicals (e.g., hexafluoropropylene oxide dimer acid [HFPO-DA; GenX]) to replace these long-chain PFAS.

Drinking water health advisories (HAs) are intended to provide an estimate of the minimum concentration of a compound that may result in adverse health effects over a lifetime.   EPA’s health advisories are not regulatory levels and are not a federally enforceable health-based limit.  Health advisories are issued as a result of ongoing research conducted as part of the rule-making process.  

In 2016, the EPA first set the health advisory levels for PFOA and PFOS (individually or combined) at 70 parts per trillion (ppt). On June 15, 2022, the EPA set new health advisory levels for four PFAS compounds that are much lower than the previous levels established in 2016.  The new Health Advisory levels are provided below:

EPA Health

These new health advisories for PFOA and PFOS represent incredibly small concentrations.  For illustration, one part per trillion (1 ppt) is approximately equal to one grain of sand in an Olympic-size swimming pool.  

It is important to note that levels contained in the health advisory are many times lower than can be detected by current EPA-approved laboratory analytical methods. 

On April 10, 2024, the EPA announced its final regulatory drinking water limits – also known as Maximum Contaminant Levels (MCLs) – for six individual PFAS compounds.  The EPA also established a Hazard Index (HI) to create an enforceable drinking water limit for two or more of four PFAS as a mixture. 

The limits announced on April 10, 2024 are: 


The Hazard Index is a tool used to evaluate health risks from simultaneous exposure to mixtures of certain chemicals.  Many PFAS are found together and in different levels and combinations.  To determine the Hazard Index for these four PFAS, the amount of each PFAS in drinking water is compared to its associated Health-Based Water Concentration (HBWC), which is the level at which no health effects are expected for that PFAS. The comparison values for each PFAS contained within the mixture are then added.  If the value is greater than 1.0, it would be an exceedance.

In addition to establishing regulatory limits for PFAS compounds, this regulation will require the following actions:

  • Public water systems must monitor for these PFAS and have three years to complete initial monitoring (by 2027), followed by ongoing compliance monitoring. Water systems must also provide the public with information on the levels of these PFAS in their drinking water beginning in 2027.
  • Public water systems have five years (by 2029) to implement solutions that reduce these PFAS if monitoring shows that drinking water levels exceed these MCLs.
  • Beginning in five years (2029), public water systems that have PFAS in drinking water which violates one or more of these MCLs must take action to reduce levels of these PFAS in their drinking water and must provide notification to the public of the violation.

The PFAS National Drinking Water Regulation announced on April 10, 2024, along with fact sheets and reference information, can be found on the EPA’s website below:

Paducah Water has a strong commitment to preserving public health. Our water is reliable, high quality and meets or exceeds all regulatory standards. Paducah Water voluntarily began monitoring PFAS in 2019, and our most current monitoring results can be found at the link below:

> Paducah Water PFAS Sample Results

It is important to note that Paducah Water does not produce PFAS. Rather, 100% of PFAS compounds that PW has identified comes from PFAS in the source water (Ohio River) and are not removed as part of the current treatment process. 

Based on the regulatory levels for PFOA and PFOS of 4.0 ppt, it is likely that PW’s water may exceed the proposed regulatory MCLs.  However, our testing indicates that our PFAS levels are very close to the regulatory limits.  We anticipate that levels of other regulated PFAS compounds are likely to be below the MCL and HI levels based on testing performed to date. 

Like many water utilities across the nation, PW is following this new regulation closely and continues to examine its potential impacts. And it will be challenging.

That said, here are several steps that PW is taking:

  1. Increase PFAS monitoring from quarterly to monthly to gather the best data possible to guide decision making and inform our customers. PW continues to sample on a voluntary basis and will also participate in all state and federal testing protocols (e.g. UCMR5).

  2. Continue to coordinate and collaborate with state and federal regulatory agencies regarding ongoing research and rule-making developments.

  3. Promote open and honest communication regarding PFAS.

  4. Examine strategies to effectively reduce levels of PFAS compounds through modification of, or addition to, the current treatment process.

The EPA estimates that only 20% of a person’s exposure to PFAS comes from drinking water.  That means that approximately 80% of a person’s PFAS exposure can come from consumer products and sources other than drinking water.  Everyday consumer products such as cosmetics, non-stick cookware, clothing, carpet, food packaging and even dental floss and toilet paper can contain PFAS.  PFAS compounds have also been found in the air and in rainwater in both urban and rural areas across the country.  That’s right – even rainwater can contain PFAS.

Avoiding exposures to all sources of PFAS may not be possible due to the wide use of PFAS in many consumer products in the world around us today.  Although it may be difficult to reduce your exposure to PFAS, the recommendations below may help. 

  1. Utilize a point-of-use filter or whole-house filtration unit that contains Granular Activated Carbon (GAC) for drinking, cooking, making ice, and preparing infant formula.   
  2. Minimize the use of products made with PFAS compounds, especially if they are non-stick, stain-resistant, or waterproof. Some sources of potential consumption of PFAS include:
    • Non-stick cookware. Instead of non-stick cookware, opt for ceramic, stainless steel, or cast iron. If the coating on your non-stick cookware begins to peel, do not use it.
    • Fast food containers and processed food packaging like French fry cartons, pizza boxes, and microwave popcorn bags.
    • Stain-resistant carpets, rugs, and furniture. Avoid using optional stain-resistant sprays and treatments on home textiles.
    • Waterproof clothing like rain jackets, gloves, and boots. Avoid using optional waterproofing sprays on clothing and footwear. Although there is little risk from having skin contact with these products (since PFAS don’t easily absorb into skin), they may shed fibers that can be inhaled or swallowed.
    • Cosmetics and personal care products. Read the ingredients on cosmetics and personal care products, like dental floss, and look for words beginning with “fluoro-”, “perfluoro-”, or “polyfluoro-”.
    • Drinking Water.  Consider installing a reverse osmosis unit or using a point-of-use filter that contains a certified carbon filter.  If bottled water is utilized, ensure that it has been treated using reverse osmosis.  
    • Dust the surfaces in your home often to reduce PFAS dust from products like carpet, upholstery, and clothing that was manufactured or treated with PFAS to resist staining and repel water.  
  3. Do not boil water in an attempt to remove PFAS compounds – these compounds are unaffected by heat.

Paducah Water operates a “conventional” surface water treatment plant.  That means PW pumps water from the Ohio River and treats the water through a process that includes coagulation, sedimentation, filtration and disinfection.  This approach has been an industry standard for water treatment for many decades.   

Although this treatment process has been very effective at meeting all current regulatory requirements for drinking water, it does not effectively remove PFAS compounds.  Therefore, PFAS compounds in the source water move through the treatment process largely unaffected and into the distribution system.

It is very likely that PW will be required to add a new treatment technology in order to maintain compliance with the PFAS regulation.  Current treatment methods for removing PFAS compounds include Granular Activated Carbon (GAC), Ion Exchange (IX) and Reverse Osmosis (RO).  An expansion of the current treatment plant to include any one of these technologies will cost many millions of dollars and will take years to complete.  Annual operational costs for PW will also be expected to increase significantly.  Further, each treatment process generates a waste stream that has concentrated levels of PFAS that must then be disposed of appropriately. 

The American Water Works Association (AWWA) estimates that more than 5,000 water utilities across the nation will be in a similar situation as PW with an annual cost of more than $3.8 billion.  PFAS is a complicated, costly, and challenging matter to address as a public utility, and many drinking water providers across the nation are confronting the same challenges.    

Regardless of the challenges, Paducah Water is committed to providing safe, reliable drinking water in a way that protects public health.  We will continue to make sound, fiscally-responsible decisions that put public health first, and it may require time and substantial investment to do so. 

US Environmental Protection Agency

Kentucky Energy and Environment Cabinet 

Centers for Disease Control and Prevention

Agency for Toxic Substances and Disease Registry 

American Water Works Association