Following changes by the Environmental Protection Agency last year, levels of man-made chemicals in Englewood’s water are now above the EPA’s newest interim health advisory levels, the city announced recently. 

The city, which supplies drinking water to approximately 57,000 people, said on its website there is not an immediate public health risk and people do not need to stop drinking their water. 

However, exposure to low concentrations of these chemicals over time can cause health effects, said Pieter Van Ry, director of the Englewood Utilities Department and the South Platte Renew, during a Jan. 23 city council special meeting. 

Englewood is not alone in facing this issue, as other water systems throughout Colorado — such as the Arapahoe County Water and Wastewater Authority in Centennial, the City of Brighton and the City of Thornton — have also detected chemicals above the EPA’s health advisory levels. 

Understanding the health advisory levels 

The EPA sets health advisory levels to “indicate the level of drinking water contamination below which adverse health effects are not expected to occur,” according to a 2022 news release.

These health advisories are non-enforceable and non-regulatory, but aim to offer information to help protect people’s health, the EPA said on its website. 

In June 2022, the EPA changed its health advisory levels for a group of man-made chemicals called PFAS (per- and poly-fluoroalkyl substances), according to Englewood’s website. 

“These are forever chemicals,” Van Ry said, explaining the chemicals date back to the 1940s and were used in materials such as firefighting foam, non-stick cookware and carpets. 

Although these chemicals were widely used for many years, in the 2000s, concern about the potential health risk of these chemicals grew when perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were detected in human blood, according to the EPA. 

“Since that time, hundreds of different PFAS have been found in water, soil, and air,” the EPA’s website states. “Many PFAS are made up of long chains of carbon-fluorine bonds, such as PFOA and PFOS, are environmentally persistent, bioaccumulative, and remain in human bodies for a long time.”

Most uses of PFOA and PFOS were voluntarily phased out by United States manufacturers in the mid-2000s, according to the EPA, but the chemicals remain in the environment due to their lack of degradation. 

EPA drastically decreased PFOA and PFOS advisory levels in 2022

In 2016, the EPA set the health advisory level for PFOA and PFOS at 70 parts per trillion, or 70 ppt. Since then, the EPA conducted further analysis and found that “the levels at which negative health effects could occur are much lower than previously understood,” the EPA said on its website. 

As a result, the EPA issued new interim health advisories for PFOA and PFOS in 2022 that were drastically lower. For PFOA, the health advisory level went from 70 ppt to 0.004 ppt. The PFOS level went from 70 ppt to 0.02 ppt.

These new interim advisories will remain in place until the EPA establishes a national primary drinking water regulation, according to the agency.

Englewood sampled the Charles Allen Water Treatment Plant in September 2022 and found its level of PFOA was 2.6 ppt and its level of PFOS was 1.9 ppt, according to its website. 

Screenshot of data provided on the City of Englewood's website regarding its testing of its water for chemicals in September 2022.

The city noted on its website that while its levels of PFOA and PFOS are above the EPA’s new advisory levels, the city is still meeting all federal and state primary drinking water standards. 

“The city is partnering with CDPHE (Colorado Department of Public Health and Environment) to continue to assess PFAS levels in our source and finished water, conduct customer outreach, and work towards reducing PFAS levels in our water supply over the long term,” the city said on its website. 

Englewood staff members are actively coordinating with the state to determine the levels of PFAS chemicals in its water through additional monitoring and evaluation, investigate treatment options, develop “feasible strategies” to reduce levels, and protect against additional pollution, per the website.

According to the EPA, there are treatment technologies that have shown the ability to remove the PFAS chemicals from drinking water systems and can be installed at a water system’s treatment plant. 

PFAS treatment was not accounted for in the city's financial plans, Van Ry said, noting the city is applying for a state grant for PFAS treatment pilot studies. 

What are the health risks?

Although the city said there is not an immediate health risk, studies have shown that exposure to the chemicals can impact people’s health.  

According to the city’s website, there is strong evidence that exposure to PFOA and PFOS impacts the immune system, increases cholesterol, decreases infant birth weight and can impact a person’s liver function. Some evidence has shown that PFOA exposure increases the risk of kidney and testicular cancer. 

There is also moderate evidence that PFAS exposure is associated with effects on thyroid hormones, as well as preeclampsia and high blood pressure during pregnancy, per the website. 

People who are more vulnerable to health impacts from these chemicals are children under the age of 6, people who are pregnant or planning to become pregnant, or people who are breastfeeding, according to the city’s website.  

For residents who want to lower their exposure to the chemicals, the city recommended using an in-home water treatment filter that is certified to eliminate levels of PFAS for drinking, cooking and preparing baby formula, per the website. 

The city also recommended reducing the use of consumer products that contain these chemicals, such as non-stick pans and cosmetics. 

“Every time we use these items, they shed these chemicals and they make their way to the receiving waters, and this is a persistent issue because these are so ubiquitous in so many different materials that are used on an everyday basis,” Van Ry said. “And they are not fully banned across the board.”

In 2022, Colorado passed a ban on “intentionally added” PFAS in consumer products, and the ban will be phased in from 2024 to 2030, according to Englewood’s website. 

It is not recommended to drink bottled water, per the city’s website, since it cannot be verified that all bottled water is below the new health advisory levels. According to the EPA, PFAS cannot be removed by heating or boiling water. 

If a resident has specific health concerns, the city recommends they consult their doctor. 

Technology challenges 

One of the difficulties of the new health advisory levels for PFOA and PFOS is that, based on current methods, they are below the level of detection and quantitation, meaning the ability to determine how much of a substance is present, according to the EPA.

“This means that it is possible for PFOA or PFOS to be present in drinking water at levels that exceed health advisories even if testing indicates no level of these chemicals,” the EPA said on its website. 

The city described the health advisory levels as “trace amounts” and “microscopic levels.” It said 0.004 ppt is “equivalent to four drops of water in 2,640 million gallons, or 4,000 Olympic-sized swimming pools.”

“These interim health advisory levels are below reliable detection abilities of most current scientific equipment, which can currently detect PFAS compounds at approximately 2 parts per trillion (2 ppt),” the city said on its website. 

“The lower the levels of PFOA and PFOS, the lower the risk,” the EPA said on its website. “This means that while PFOA and PFOS may be present in drinking water in trace concentrations that cannot be measured, water provided by these systems that test but do not detect PFOA or PFOS is of lower risk than if they are found at measurable levels.”

The EPA said it is continuing to conduct research on how it can improve the ability to measure the PFAS chemicals at lower levels. 

Those interested in staying updated on Englewood’s progress as well as accessing additional resources can visit englewoodco.gov/pfas.