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:
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.
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 monitors PFAS quarterly, and our most current monitoring results are provided below:
PFAS research and the understanding of “safe” levels of PFAS exposure continues to evolve. On June 14, 2022 PW’s water was well below the recommended health advisory levels. Overnight, PW’s water exceeds two of the four levels contained in the new health advisory. Even the laboratory methods used to characterize PFAS levels are not adequate to determine the levels contained within the new health advisory. Ongoing monitoring and research will be required at a local, state and national level. And it will be challenging.
That said, here are several steps that PW will be taking:
Avoiding all exposures to all sources of PFAS may not be possible due to the wide use of PFAS in many consumer products, and most people in the United States have PFAS compounds in their blood. PFAS can accumulate and remain in the human body for long periods of time. However, the recommendations below can help reduce your PFAS exposure.
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 process has been very effective at meeting all current regulatory requirements for drinking water, this treatment process 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.
In order to remove PFAS as part of the water treatment process, PW will need to alter our treatment method. 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 require tens of millions of dollars and will take years to complete. Annual operational costs for PW will increase by hundreds of thousands of dollars per year. Further, each treatment process generates a waste stream that has concentrated levels of PFAS that must then be disposed of appropriately. It should also be noted that it is unlikely that any of these treatment methods are capable of achieving removal of PFOA or PFOS to a level that meets the 2022 Health Advisory of 0.004 ppt and 0.02 ppt respectively. As you can see, 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.
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 will require time and substantial investment to do so.
US Environmental Protection Agency
Kentucky Energy and Environment Cabinet
Centers for Disease Control and Prevention