NEW TECHNOLOGY PROTECTS PUBLIC HEALTH BY DESTROYING PFAS IN WASTEWATER
JOHN BROCKGREITENS, VICE PRESIDENT OF RESEARCH AND DEVELOPMENT AT CLAROS TECHNOLOGIES
The per- and poly-fluoroalkyl substances (PFAS) that resist heat, fire, stains, grease, and water have widespread use in everything from nonstick pans to firefighting foam. Unfortunately, widespread use has led to widespread pollution, which seriously endangers public health.
The carbon-fluorine (C-F) bond of PFAS is the strongest one in organic chemistry and doesn’t break down naturally, which is why they are called “forever chemicals.” They could just as aptly be called “everywhere chemicals” because they are found in water, soil, and air globally.
People are exposed by consuming water or food, using products, or breathing air contaminated with persistent organic pollutants, which accumulate in the body. The Centers for Disease Control and Prevention (CDC) reported that PFAS were found in the blood of 97% of Americans. That’s concerning because the National Institutes of Health (NIH) has linked PFAS to an increased risk of obesity and some cancers, reduced fertility and fetal growth, and weakened immunity.
These persistent chemicals are highly soluble. A 2022 analysis of drinking water from 41 cities in 15 countries detected PFAS in every sample. Industrial wastewater has been targeted as a major source of PFAS pollution. The Environmental Working Group (EWG) created a map of 41,828 U.S. industrial and municipal sites that are “suspected of making, using or releasing PFAS.”
If untreated, industrial sites send PFAS downstream to wastewater treatment plants that are often unprepared to effectively treat it. Conventional wastewater treatment solutions typically capture toxins in filters and then incinerate the filter media, which only breaks down long-chain PFAS compounds into small-chain ones. Other traditional solutions include putting the spent filters in landfills where the PFAS show up in runoff. That is likely why a correlation has been found between the number of wastewater treatment plants within a watershed and PFAS concentrations in public water supplies.
PFAS remediation is in its infancy and has unique challenges. Most tests detect fewer than 40 PFAS compounds and testing technology is not keeping pace with the growing list of regulated compounds. There are a number of methods to filter PFAS from wastewater, with reverse osmosis, foam fractionation, ion resins, and granulated activated carbon being the most common. Reverse osmosis is considered one of the most effective methods, but high capital expenses compounded by high energy costs have prevented widespread adoption.
Once filtered, the vexing problem of PFAS is only concentrated, not destroyed. Filters and liquid concentrates laden with PFAS are often sent to landfills or incinerated. However, both methods are likely to be outlawed soon, because they lead to re-contamination. Innovative technologies such as the ones developed and incubated at the University of Minnesota and commercialized by
Claros Technologies could destroy PFAS in wastewater and allow for the safe reuse of water.
The first step is comprehensive testing that utilizes compound-specific and class-based methods. Claros Technologies is one of only three accredited U.S. labs that can detect short- and ultrashort-chain PFAS. The second step is PFAS capture and concentration. This new method can be used alone or with existing systems to filter millions of gallons of water to make a few gallons of PFAS
concentrate. The final step is permanent destruction through defluorination. Proprietary technology called the Elemental uses a photochemical process to break the C-F bond.
This comprehensive PFAS-remediation strategy allows for the safe reuse of wastewater and safeguards human and environmental health. These new approaches and technologies can help industries show exemplary leadership and stewardship in the movement toward a circular economy.