UNSW Sydney researchers say branched PFOA may be more prevalent in the environment than predicted.
A new study has revealed there may be a significant underestimation of a specific type of PFAS ‘forever chemical’ in the environment.
Researchers from UNSW Sydney found that branched perfluorooctanoic acid (PFOA) was more prevalent than expected in firefighting foam. PFOA is classified as a human carcinogen by the International Agency for Research on Cancer.
Firefighting foams have historically been composed of Per- and poly-fluoroalkyl substances, known collectively as PFAS, which have been linked to environmental and health issues because they can take hundreds or even thousands of years to naturally break down.
Low traces of PFAS are believed to now be present in more than 99% of the global population and there are growing concerns about the level of contamination in water supplies, including drinking water.
In a paper published in Water Research, the UNSW team led by Professor Denis O’Carroll, Professor Naresh Kumar, Professor Michael Manefield and Dr Matthew Lee, showed that concentrations of branched PFOA in firefighting foam would double after time in the environment.
The researchers conducted what is known as a TOPA – a total oxidisable precursor assay – which simulates the oxidation process that helps create regulated PFAS naturally in the environment, but at a much faster speed.
“[We took] the firefighting foam and put it through a test to mimic what would happen to those chemical compounds in the environment. And we found that this branched PFOA was actually an important product of that process,” said Prof. O’Carroll, from UNSW’s School of Civil and Environmental Engineering.
“PFOA also exists in a linear form, but people have not really been looking or analysing the amount of branched PFOA. But in our samples we found that about 50% was linear and 50% was branched after TOPA.”
