What is PFAS?

Per-and Polyfluoroalkyl Substances (PFAS) are a group of manmade chemicals that have been manufactured in a variety of industries around the globe. Exposure to levels of PFAS above health advisory guidelines has been linked to health problems including liver damage, thyroid disease, decreased fertility, lower birth weight, asthma, high blood pressure, and cancer. Some PFAS persist in the environment, and people can be exposed to these chemicals through air, indoor dust, food, drinking water, and various consumer products.

Fortunately, drinking water from public water providers meets the Colorado Primary Drinking Water Regulations and is safe to drink. Learn more about PFAS:

Identifying PFAS in Groundwater in Adams County

In 2021, Tri-County Health Department and Colorado Department of Public Health and Environment launched a project to identify whether there could be PFAS contamination in 11 designated areas impacting private residential wells by collecting and analyzing PFAS samples from residential wells within the designated areas. The goal was to test private wells in selected neighborhoods to learn if per- and polyfluoroalkyl substances, or PFAS, were in the groundwater. In total, 10 private wells were sampled. Thirty-one different types of PFAS were tested for in each sample.

All of the water samples collected during this project were below detection levels of 10 ppt for the PFAS compounds PFOA and PFOS which are included in the current EPA health advisory level of 70 ppt. Nine of the ten samples collected during this project were below detection levels ranging from 10 ppt to 25 ppt, (shown in Table 1) for all of the PFAS compounds analyzed. One sample had measurable levels of two of the PFAS compounds. The results for these two compounds were Perfluoro-n-hexanoic acid (PFHxA) at 11.5 ng/l and Perfluoro-n-pentanoic acid (PFPeA) at 16.6 ng/l. These two compounds are not part of the current EPA health advisory.

Additional details about the 2021 PFAS sampling project in Adams County can be found in the final report.

What are PFAS and the potential health effects from exposure?

PFAS are a family of human-made chemicals that have been used for decades in products like food packaging, carpets, non-stick products, other household items, medical supplies, and firefighting foam due to their ability to resist heat, oil, stains, grease, and water. According to EPA, studies indicate exposure to PFOA and PFOS may result in adverse health effects. For example, developmental effects to fetuses during pregnancy or to breastfed infants can occur over weeks of exposure (e.g., low birth weight, accelerated puberty, skeletal variations). Years to decades of exposure may lead to liver damage, reduced vaccine response and thyroid effects, and other health impacts. We know the most about PFOA and PFOS, but there are other chemicals in the PFAS family such as PFHpA, PFHxS, PFBS, and PFNA. These chemicals may have similar impacts on humans. The health impacts of PFAS is the current focus of much research. As new studies become available, our understanding of the health impacts of these chemicals in humans will continue to grow.

Health-based guidelines to be updated

Based on new science, EPA is currently working to update health-based guidelines and develop a drinking water regulation for PFOA and PFOS.

In November, 2021, EPA released draft documents it will use to develop regulations and health guidelines. This new information is currently under review by the agency's Science Advisory Board and may change before final health-based recommendations are determined.

What do these test results mean for my health and do I need to do anything?

Whether or not a person experiences health impacts from exposure to PFAS depends on many factors. Some of these factors include how much PFAS you were exposed to, for how long you were exposed, your medical history and genetics. If you are concerned, please talk to your doctor and learn more about the chemicals. Alternative considerations if the drinking water contains PFAS are bottled water or water treated by a reverse osmosis system. Please know bottled water or reverse osmosis systems may not have added benefits that tap water has. Tap water is significantly less expensive than bottled water and does not result in as much plastic waste as bottled water production. 

Where can I get more information?

Scientists continue to study the health impacts of these chemicals. As we keep learning more about how these substances affect health, the current EPA health advisory will likely be revised. For the most up to date information about PFAS or if you have more questions about PFAS, please visit If you have additional questions or concerns, contact Adams County Health Department at 303.288.6816.

Update: On June 15, 2022, the EPA released updated Health Advisory for PFAS.  The new advisories are:

  • Interim updated health advisory for PFOA = 0.004 ppt
  • Interim updated health advisory for PFOS = 0.02 ppt
  • Final health advisory for GenX chemicals = 10 ppt
  • Final health advisory for PFBS = 2,000 ppt

These values are much lower than the previous advisory. Adams County Health Department is continuing to follow developments at the state and federal levels including the development of a Maximum Contaminant Level (MCL) by the EPA.  We will share information is it becomes available.

How do I know what the PFAS levels are in my drinking water?

 If you are on a public water system- You may be able to view your water system’s testing results on the CDPHE webpage . If you do not see your system listed, you can call your system administrator to ask them if they have tested and if they haven’t, whether they will.

If you are on a private well you can contact the CDPHE PFAS sampling program to request sampling of your well. They will assess the risk associated with your well and you may be chosen to receive free sampling. You can also contact the Adams County Health Department at 303.288.6816 to explore private well sampling.   

For additional information and to reduce your exposure, please visit the CPDHE website and this resource document for at-home water filters


It is the policy and position of the Adams County Health Department that the following information regarding your private well should not be part of the public record and therefore should not be released to the public under the Colorado Open Records Act: (a) personal data including names, addresses, telephone numbers, personal financial information, and other personal information of past or present users of private water wells; (b) private water well sampling results at a specific latitude and longitude locations; (c) source water information, including latitude/longitude coordinates, source water assessment delineations of areas that contribute the raw water, and the susceptibility of those sources to potential sources of contamination.


Environmental Health Office

7190 Colorado Blvd.
Ste. 200
Commerce City, CO 80022