Monash researchers develop new technique to combat toxic PFAS contamination
Contamination from per- and poly-fluoroalkyl substances (PFAS) has become an increasing environmental concern.
PFASs are a class of manufactured chemicals that have been used since the 1950s to make products that resist heat, stains, grease and water.
They can be found in many items including furniture, foams used for firefighting, food containers, make-up and personal care products and cleaning products.
The release of PFAS into the environment is a problem because these chemicals are highly persistent, have been shown to be toxic to fish and some
animals, and can accumulate in the bodies of fish, animals and people who come into contact with them.
“Once in the environment these compounds do not break down,” said Associate Professor Rico Tabor from the Monash School of Chemistry and co-author of a new study in Environmental Science & Technology.
Professor Tabor’s research team have developed a new method to capture PFAS detergents (the most mobile and troublesome form of the contamination) using tiny carbon-coated capsules filled with olive oil.
The capsules are only around one fiftieth of the diameter of a human hair across, allowing them to penetrate soils and follow water percolation.
“Contamination from PFASs is a threat to the environment,” Associate Professor Tabor said.
“Their accumulation in water and soil means that they are being detected in agricultural land, water treatment facilities and even drinking water sources,” he said.
“Particularly worrying are detergent forms of these substances, as they can easily move between soil, sediment and water, ending up almost everywhere.
“For the first time, we show that microcapsules can be used to capture mobile PFAS contamination.
"The capsules work almost like synthetic microbes, 'eating' contaminants and retaining them inside."
The new research is part of the PhD thesis work by student Muthana Ali, supported by supervisors Associate Professor Tabor and Professor Mainak Majumder from the Monash Faculty of Engineering.
Melbourne’s $6.7bn Westgate Tunnel is currently at a standstill following the detection of PFASs in soil removed during excavation at the site.
“It is clear that methods for decontaminating PFASs from soil and water are urgently needed,” Associate Professor Tabor said.