How scientists are making PFAS harmless, safe to eat
THE threat of PFAS contamination hanging over Oakey residents could be a thing of the past after scientists developed a compound that neutralised the hazardous chemicals.
Cooperative Research Centre for Contamination Assessment and Remediation of the Environment researchers developed a modified clay that bonds to the per- and poly-fluoroalkyl (PFAS) chemicals.
It locked up the chemicals preventing human and animal digestive systems from absorbing them.
Called nano-matCARE, the microscopic clay particles can be used on PFAS contaminated water, soil or concrete.
Tests at the University of Newcastle's Global Centre for Environmental Remediation show that nano-matCARE immobilised 99.97per cent of the PFAS chemical perfluorooctanesulfonic acid (PFOS) in contaminated concrete.
After 10 months, more than 99.61per cent of the chemical remained immobilised.
Lead researcher Professor Ravi Naidu expects governments and businesses will use the compound to clean the thousands of PFAS-contaminated site across Australia.
"Once nano-matCare locks up the PFAS chemicals they become very stable," he said.
"If applied to a river the particles would sink to the river bed and sit in the sediment."
It makes the chemicals as harmless as regular sand.
"If a fish swallowed the particles they would pass through their digestive system," Prof Naidu said
"Whatever you ingest, it only gets absorbed by your gut if it is present in a form that your body allows it to absorb."
The clay works similar to Phoslock bentonite clay, developed by the CSIRO. It binds to phosphates in rivers, lakes and dams, rendering them inert and reducing blue green algae blooms.
"It is about risk management," Prof Naidu said.
"We know we cannot remove PFAS chemicals from the environment, but we can lock them up."