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In a major breakthrough aimed at managing the long-term environmental impact of anthropogenic activity, American researchers have found a method to be able to trace the origin and the destination of forever chemicals.
These chemicals that are scientifically known as per-and polyfluoroalkyl substances (PFAS) are generally useful in applications such as water-proofing, heat resistance, detergents, food packaging and non-stick technologies. They are known to stay in the environment virtually forever and contribute to environmental degradation which adversely impacts the health of all organisms including human beings.
Researchers at The University of Texas at Austin have used a technique which involves magnetic fields and radio waves to track the spread of these chemicals in the ecosystems across the globe.
“The technique involves passing samples through a strong magnetic field then reading the burst of radio waves their atoms emit. This reveals the composition of carbon isotopes in the molecule and gives the chemical its fingerprint, a feat that had not previously been achieved with forever chemicals,” an article published on the website of the American university mentioned on August 7.
The research paper is co-authored by Cornelia Rasmussen and David Hoffman and the new technique was described in detail in a paper published in the journal Environmental Science & Technology on July 18.
It is also reported that America’s Environmental Protection Agency (EPA) plans to regulate these chemicals and try to eliminate most of them from drinking water.
What causes these chemicals to stay in the environment for exceptionally long durations is the massive strength of their bonds.
The article explained that the super strong molecular bonds that give forever chemicals their handy characteristics — which are put to use in everything from fire retardants to non-stick surfaces and slow-release drugs — also keep them from breaking down in the environment.
This causes them to build up as pollution in soil and organic material to which they readily stick.
“However, the molecular bonds of the chemicals also make them difficult to trace. That’s because conventional chemical fingerprinting involves breaking molecules apart in a mass spectrometer which doesn’t work well with the tough molecular bonds of forever chemicals,” the article mentioned.
Owing to the strength of the intermolecular forces in the composition of these forever chemicals, the researchers opted for a technology known as nuclear magnetic resonance (NMR) spectroscopy.
The technology is used to measure a molecule’s structure and identify its isotopes without breaking it apart.
“Isotopes refer to chemical elements with differences in the number of neutrons in its atoms. Forever chemicals are made by bonding carbon isotopes to the element fluorine, which almost never happens in nature. Once the molecular bonds form, they are virtually unbreakable,” the article stated.
What is unique about these chemicals is they are made by bonding carbon isotopes to elemental fluorine — something that almost never happens in nature without human involvement.
Once these super-strong molecular bonds are formed, they are virtually unbreakable.
“The researchers’ technique uses the NMR instrument alongside their own computational tools to determine the mix of carbon isotopes at each position in the molecule. Because the mix of carbon isotopes bonding to each fluorine atom is unique to how the chemical was manufactured, this information can be used like a fingerprint to trace a chemical,” it is explained.
It’s like a built-in barcode for molecules, the research’s co-author, David Hoffman, an associate professor at the Department of Molecular Biosciences in UT’s College of Natural Sciences, remarked.
“Part of the reason this has worked out so well is because we’re assembling tools from different areas of science [chemistry and geosciences] that don’t normally mix and using them to do something no one’s really done before,” he was quoted.
It is reported that the researchers tested the finding of their research on samples that included pharmaceuticals and a widely used pesticide.
The two co-authors of the research are presently engaged in conducting a pilot study to check how the technique will fare on pollutants that show up in the city of Austin’s creeks and wastewater.
“If successful, the technique could be useful for state and federal agencies who want to track the spread of water-borne forever chemicals,” the article mentioned.
Rasmussen was quoted as saying that the work has opened up a new layer of isotope information in organic chemistry that could find diverse applications transcending the scope of tracking forever chemicals, such as detecting counterfeit drugs or astrobiology.
“It’s given us a whole range of possibilities to learn really interesting things about metabolism on early Earth,” she was quoted.
“It could even tell us whether organics on Mars are the last remnants of some ancient Martian life,” the researcher added.