Researchers unveil method to detect ‘forever chemicals’ in less than 3 minutes

PFAS have earned the nickname “forever chemicals” for good reason: man-made compounds, which can take thousands of years to degrade and are found in everything from grease-proof food packaging to clothing water repellents, have made their way into almost half of the tap water supply in the United States.

Now, in a study presented in the Journal of Hazardous MaterialsNew Jersey Institute of Technology chemists have demonstrated a new laboratory method for detecting trace amounts of PFAS in food packaging materials, water and soil samples in just three minutes or less.

The researchers say their approach could significantly accelerate efforts to study and address the bioaccumulation of PFAS in the environment, including more than $2 billion in EPA grants from the President’s bipartisan infrastructure bill. Biden for states to test water quality and address emerging contaminants.

“There are thousands of different species of PFAS, but we have not yet understood the extent of their distribution in our environment because current testing methods are expensive and time-consuming, taking hours for preparation and analysis of the samples in some cases,” said Hao Chen, corresponding author of the study and professor of chemistry at NJIT. “Our study demonstrates that this is a much faster, more sensitive and versatile method that can monitor contamination in our drinking water, land and consumer products in minutes.”

Chen and his colleagues say the new method, involving an ionization technique for analyzing the molecular composition of samples called paper spray mass spectrometry (PS-MS), is 10 to 100 times more sensitive than the current standard technique for PFAS testing, liquid chromatography/mass spectrometry.

“PFAS can be ionized and rapidly detected by a high-resolution mass spectrometer, which gives a clear view of each PFAS species present and the degree of contamination down to a parts per trillion (ppt) level,” explained Chen.

“For more complex matrices like soil, we applied a related method called desalination paper spray mass spectrometry (DPS-MS) that removes salts that normally suppress the ion signal of PFAS. Together, they significantly improve our ability to detect these compounds.”

“Our detection limit for PFAS is approximately 1 ppt. For context, this amount was compared to a drop of water in 20 Olympic swimming pools,” added Md. Tanim-Al Hassan, first author of the paper and holds a Ph.D. student in chemistry at NJIT.

In tests, the team was able to detect PFAS in a minute or less by directly analyzing pieces of various food packaging materials, including microwave popcorn paper, instant noodle boxes, as well as packaging of fries and hamburgers from two multinational fast food chains.

The analysis revealed traces of 11 different PFAS molecules, including common types that have been linked to increased cancer risk and immune system suppression, such as PFOA (perfluorooctanoic acid) and PFOS (perfluorooctanesulfonic acid). .

During their water analysis, the team detected traces of PFOA in samples of local tap water in less than two minutes, while finding no traces of PFAS in samples taken from the filtered water from the university fountains.

“The EPA has already proposed establishing maximum contamination levels (MCLs) for six PFAS in drinking water nationwide, and PFOA and PFOS are among them,” said Mengyan Li, co- study author and associate professor of environmental sciences at NJIT. “This analytical method could facilitate more intensive controls for toxic PFAS that might be needed under such a proposal to protect the safety of our water supply.”

Using DPS-MS, the team also identified two PFAS species from just 40 mg of soil in less than three minutes.

Already, the team’s rapid detection method is being tested for use alongside cutting-edge techniques to remediate PFAS that are being developed at NJIT’s BioSMART Center.

“Remarkably, in our laboratory, we were able to combine this analytical method with a new degradation catalyst, which degrades 98.7% of PFAS present in drinking water samples within three hours,” said co-author Wunmi Sadik. of the study and chairman of the chemistry department at NJIT. and environmental sciences.

“This work could have a national impact, but the immediate effect will be felt in the Northeast region. About 10% of New Jersey’s 9.2 million residents have high levels of perfluorooctanoic acid in their water drinking water, compared to the national average of 1.9%.”

According to Chen, these advances could also have a rapid impact on the surveillance of consumer products, from cosmetics and drugs to fresh and processed foods. The team also plans to demonstrate the method’s capabilities in air monitoring.

“In the short term, this could be extremely useful in ensuring the safety of food products…it could allow agricultural products to be more effectively monitored for PFAS contamination, for example,” Chen explained. “Our method could also advance the study of airborne PFAS in a manner similar to what we demonstrated in this study, which would further help us address this widespread environmental problem.”