Breakthrough Detection Method Identifies "Forever Chemicals" in Half of U.S. Tap Water within Minutes

Chemists have devised a new technique to identify PFAS compounds in less than three minutes, providing a fast and sensitive solution for environmental surveillance and the problem of widespread PFAS contamination.

One of the quickest and most sensitive methods for identifying the harmful per- and poly-fluoroalkyl substances (PFAS) that accumulate in our environment has been reported by researchers. These are linked to various health risks, including cancers and birth defects.

PFAS, often referred to as "forever chemicals" due to their man-made origin and their extremely slow rate of degradation -- sometimes taking thousands of years -- are present in a multitude of items, from grease-resistant food packaging to water-repellent clothing. They have contaminated nearly half of all U.S. tap water supplies.

Highlighted in the Journal of Hazardous Materials from Elsevier, New Jersey Institute of Technology (NJIT) chemists have shown that traces of PFAS from food packaging, water, and soil samples can be detected in less than three minutes with a new lab process.

According to the researchers, their method could substantially accelerate efforts to study and tackle the bioaccumulation of PFAS in the environment. This includes more than $2 billion in EPA grant funding from the Bipartisan Infrastructure Law of President Biden for states to conduct water quality testing and treatment for these emerging contaminants.

Hao Chen, the corresponding author of the study and an NJIT chemistry professor, states that their study demonstrates a faster, sensitive, and adaptable method for detecting contamination in drinking water, land, and consumer products within minutes. According to Chen, this is crucial because thousands of different PFAS species exist, and their distribution in our environment is not fully understood due to the high costs and lengthy duration of current testing methods.

Chen and his colleagues claim that their new method, involving an ionization technique for analyzing the molecular composition of sample materials known as paper spray mass spectrometry (PS-MS), is 10 to 100 times more sensitive than the currently available standard technique for PFAS testing, liquid chromatography/mass spectrometry.

Chen explained that PFAS can be ionized and quickly detected by a high-resolution mass spectrometer, which clearly exhibits each PFAS species present and the extent of contamination down to a parts-per-trillion (ppt) level. Additionally, for more complex matrices like soil, a method called desalting paper spray mass spectrometry (DPS-MS) is used to wash away salts that usually suppress the ion signal of PFAS, greatly enhancing our ability to detect these compounds.

NJIT Ph.D. chemistry student and the paper's first author, Md Tanim-Al Hassan, added that their limit of detection for PFAS is approximately 1 ppt, which is akin to a drop of water in 20 Olympic-sized swimming pools.

In their experiments, the team was able to identify PFAS in less than one minute by directly examining pieces of various food packaging materials, including microwave popcorn paper, instant noodle boxes, and burger and fry packaging from two multinational fast food chains.

They found traces of 11 different PFAS molecules in their analysis, including common types linked to higher cancer risk and immune system suppression, such as PFOA (Perfluorooctanoic Acid) and PFOS (Perfluorooctanesulfonic acid).

In their water examination, the team detected traces of PFOA in samples of local tap water in less than two minutes, while no PFAS were found in samples taken from the university’s filtered fountain water.

NJIT associate professor of environmental sciences and study co-author, Mengyan Li, stated that their analytical method could help more intensive screenings for toxic PFAS that may be necessary to protect our water supply safety as per the EPA's proposal to establish maximum contamination levels (MCLs) for six PFAS in drinking water nationwide, including PFOA and PFOS.

Also, the team managed to identify two PFAS species from as little as 40 milligrams of soil in less than three minutes using DPS-MS.

The team's speedy detection method is already being tested for use in conjunction with advanced approaches for treating PFAS that are being developed at NJIT's BioSMART Center.

“Remarkably, in our lab, we were able to couple this analytical method to a novel degradation catalyst, which degrades 98.7% of PFAS in drinking water samples within three hours,” said Wunmi Sadik, study co-author and chair of NJIT’s Department of Chemistry and Environmental Sciences. “This work may have a national impact, but the immediate effect will be felt in the Northeast area. Roughly 10% of 9.2 million New Jersians have high levels of perfluorooctanoic acid in their drinking water compared to the national average of 1.9%.” 

Chen says the advance could also have a swift impact on the monitoring of consumer products, from cosmetics and medicine to fresh and processed foods. The team plans to demonstrate the method’s capabilities for air monitoring as well.

“Near term, this could be extremely useful for ensuring the safety of food products … it may allow farming produce to be more efficiently monitored for PFAS contamination for example,” explained Chen. “Our method may also advance the study of airborne PFAS in a similar way to what we’ve demonstrated in this study, which would further help us address this widespread environmental issue.”