Tips for Taps Blog

GenX: The “Regrettable Substitution"

GenX: The “Regrettable Substitution"


The Replacement For Known Carcinogen PFOA Might Be Just as Harmful as Its Predecessor

You might assume that once a chemical is found to be toxic, it gets regulated and products swap the chemical out for safer options. However, substitution chemicals are often similar in structure and form to the chemical they are trying to replace, resulting in similar toxicity effects. In some cases, the substitute is found to be just as toxic or even more toxic than the chemical it is replacing. This common practice in the production of everyday products is known as a Regrettable Substitution.

Unfortunately, the story behind GenX is no exception.

In 2006, U.S. manufacturers voluntarily phased out 183 major poly- perfluoroalkyl substances (PFAS) after the Environmental Protection Agency (EPA) found that PFAS caused liver damage, birth defects in newborns, cancer, and several other negative health effects. PFAS are ubiquitous in products ranging from food packaging, nonstick cookware, waterproof clothing, cleaning chemicals, and more

Multiple manufacturers replaced PFAS compounds with a chemical called GenX. Little attention was paid to GenX–itself a PFAS–until high levels of GenX were found in North Carolina’s Cape Fear River–upstream of drinking water for a quarter million people. 

Now, yet another harmful PFAS exists in the environment.

What Are GenX Chemicals?

Named after the technology used to make Teflon—a non-stick chemical coating for cookware—GenX (chemical name: perfluoro-2-propoxypropanoic acid) is a part of the PFAS chemical family. While GenX is technically considered one chemical, its byproducts, salt form, and ion form are collectively called GenX chemicals. 

The Story Behind GenX

Most often, the EPA allows manufacturers to produce a new chemical without regulation. However, in some cases the EPA and the manufacturer sign a tentative agreement known as a Consent Order that puts boundaries on use of the chemical.

In 2009, the EPA signed a Consent Order with DuPont (now Chemours) allowing Chemours to replace Perfluorooctanoic acid (PFOA)—the specific PFAS in Teflon material—with GenX. Per the Consent Order, Chemours was required to capture 99% of GenX waste and conduct environmental and health studies during widespread manufacturing. 

Citizens grew concerned that Chemours violated the Consent Order when a 2016 study found GenX levels up to 4560 parts per trillion (PPT) downstream of the Chemours Plant. These levels were 30 times higher than North Carolina’s current health goal for GenX of 140 PPT. North Carolina’s Lower Cape Fear River Basin (downstream of Chemours) provides tap water to 250,000 residents. 

Figure 1 indicates that once sampling for GenX began, the contaminant was found in levels exceeding health goals repeatedly over time. Out of the 160 days sampled, 57 of those days had detections above the 140 PPT health goal.

GenX Levels at Cape Fear

Figure 1. The graph above plots GenX concentrations in parts per trillion (PPT) detected at the Chemours discharge point between June 19, 2017 and October 1, 2019. Data Source: NC DEQ: GenX Surface Water Sampling Sites.

Chemours asserted that they did not violate the Consent Order. Rather, Chemours disclosed that they had discharged GenX as a byproduct of a vinyl-making process not related to Teflon regulated under the Consent Order. They revealed this practice had been underway since 1980! 

This legal distinction about the source of GenX in the water did not stop a flurry of lawsuits against Chemours starting in 2017. The Cape Fear Public Utility Authority (CFPUA) and Cape Fear River Watch sued Chemours for violating the Clean Water Act, stating that Chemours recklessly discharged GenX while producing vinyl all those years. That same year, 3 class action lawsuits were filed against Chemours. In early 2018, 70 private well owners sued Chemours for damages associated with GenX contaminated water. 

The CFPUA and Cape Fear River Watch settled their lawsuit with a 12 million dollar fine and an updated, wide-reaching Consent Order in November of 2018.

In October of 2020, North Carolina’s Attorney General sued Chemours seeking financial compensation for investigating GenX contamination and remediating drinking water supplies. These lawsuits are ongoing and likely to draw out for years.

Where Else Has GenX Been Detected?

GenX has been detected in waters near chemical plants all over the world. Elevated GenX was found in the Rhine River in Germany, the Rhine-Meuse Delta in the Netherlands, the Xiaoqing River in China, and the Ohio River in the United States. There is also GenX contamination from waste dumped outside of Houston, Texas.

As GenX is not regulated, water utilities are not currently required to treat drinking water for GenX.

What Are the Health Effects of GenX Chemicals? 

Chemours designed GenX to be less environmentally and biologically persistent than PFOA, yet very little toxicological data exists to support this claim. Recent animal studies found links between GenX oral exposure and negative effects to the kidneys, blood, and immune system and cancer in the liver, pancreas, and testicles. 

While researchers are ramping up studies to understand GenX’s toxicological effects, one question still remains unanswered… What is the compounding health effect of exposure to multiple PFAS?

Just under 5,000 PFAS exist in the environment and we’ve studied about 50 of them to varying degrees. What’s more, around 150 chemicals were introduced in the 2009 Consent Order as replacements for the phased-out PFAS. GenX was just one of them. Several other PFAS were also created as a result of GenX production. 

We have yet to determine how all these PFAS might interact to affect human health.

Test Your Water with Tap Score

Concerned About GenX at the Tap?

Learning about potential water contamination can be overwhelming, but the best first step is to get your water tested. SimpleLab provides a range of water testing kits, including a GenX and PFAS Water Test.

Have questions about GenX, water testing, or anything in between? Reach out to SimpleLab’s team of experts and scientists at 

back to top