PFAS in Drinking Water: The Forever Chemical Explained

Per- and polyfluoroalkyl substances, commonly known as PFAS, have become one of the most discussed topics in water quality over the past decade. Often called "forever chemicals" because of their extraordinary resistance to breaking down in the environment, PFAS have been detected in water supplies across the United States, including in several Colorado communities. Understanding what these chemicals are and how they relate to your drinking water is an important part of being an informed consumer.

What Are PFAS?

PFAS are a large family of synthetic chemicals that have been manufactured and used in a wide range of industrial and consumer products since the 1940s. The family includes over 12,000 individual compounds, though the most studied are PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid).

The defining characteristic of PFAS is the carbon-fluorine bond, one of the strongest chemical bonds in organic chemistry. This bond makes PFAS extremely stable and resistant to heat, water, grease, and degradation. These properties made them valuable in manufacturing products like nonstick cookware, water-resistant clothing, food packaging, firefighting foams, and stain-resistant fabrics.

However, the same durability that makes PFAS useful in products also means they persist in the environment for extremely long periods. They do not naturally break down through sunlight, water, or microbial activity the way many other organic compounds do. Once released into the environment, they can accumulate in soil, groundwater, and surface water indefinitely.

How PFAS Enter Drinking Water

PFAS enter water supplies through several pathways. The most significant sources include:

• Aqueous film-forming foam (AFFF) -- Firefighting foams containing PFAS have been used extensively at military bases, airports, and industrial fire training facilities. When these foams are applied during training exercises or emergency responses, they can seep into the ground and contaminate underlying aquifers.
• Industrial discharge -- Manufacturing facilities that use PFAS in their processes may release these compounds through wastewater discharge, air emissions, or solid waste disposal.
• Wastewater treatment plants -- Conventional wastewater treatment processes were not designed to remove PFAS. When treated wastewater is discharged into rivers or used for irrigation, PFAS can enter the broader water cycle.
• Landfill leachate -- Consumer products containing PFAS that are disposed of in landfills can leach these chemicals into groundwater over time.
• Biosolids application -- When treated sewage sludge (biosolids) is applied to agricultural land as fertilizer, any PFAS present in the sludge can migrate into soil and groundwater.

EPA Guidelines and the New National Standard

For many years, the EPA issued only non-enforceable health advisories for PFAS in drinking water. In 2016, the agency set a combined health advisory level of 70 parts per trillion (ppt) for PFOA and PFOS. While this provided guidance, it did not require water systems to test for or reduce these compounds.

In April 2024, the EPA finalized the first-ever legally enforceable National Primary Drinking Water Regulation for six PFAS compounds. The new standards set Maximum Contaminant Levels (MCLs) of 4 parts per trillion for PFOA and PFOS individually, and established limits for four additional PFAS compounds including PFHxS, PFNA, PFDA, and GenX chemicals.

Public water systems have until 2029 to comply with the new standards. This includes conducting monitoring, notifying the public if levels exceed the MCLs, and implementing treatment to reduce PFAS if necessary.

PFAS in Colorado

Colorado has been at the forefront of state-level PFAS monitoring and response. The Colorado Department of Public Health and Environment (CDPHE) has conducted extensive testing of water systems throughout the state, particularly in areas near known PFAS sources such as military installations and industrial sites.

Communities near Peterson Space Force Base in Colorado Springs, Buckley Space Force Base in Aurora, and the former Lowry Landfill in Denver have been identified as areas where PFAS contamination has affected groundwater. The state has worked with affected communities to provide alternative water supplies, conduct additional testing, and develop remediation plans.

Colorado has also adopted its own PFAS standards that in some cases are more stringent than the previous federal advisories, reflecting the state's commitment to addressing these contaminants proactively.

What Homeowners Can Do

If you are concerned about PFAS in your drinking water, there are practical steps you can take to learn more and reduce your exposure:

• Review your water quality report -- Check whether your utility has tested for PFAS and what the results show. Many Colorado utilities now include PFAS data in their annual Consumer Confidence Reports.
• Request a home water analysis -- A professional water analysis can test for PFAS at your specific tap, providing data that is more relevant to your household than system-wide averages.
• Consider point-of-use treatment -- Certain treatment technologies have been shown to reduce PFAS levels in drinking water. Activated carbon filters, reverse osmosis systems, and ion exchange systems are among the technologies that have demonstrated effectiveness against specific PFAS compounds.
• Stay informed -- PFAS regulation is evolving rapidly. Following updates from the EPA, CDPHE, and your local utility helps you stay current on what is being done at the system level.

The science around PFAS continues to develop, and regulation is catching up. Being informed about these compounds -- without alarm -- puts you in the best position to make thoughtful decisions about your household water.

Disclaimer: The Water Awareness Foundation is an independent educational organization. We are not affiliated with any government agency, water utility, or regulatory body. The information in this article is for educational purposes only and should not be interpreted as medical or legal advice.