PFAS contamination is a puzzle scientists are yet to solve — and it was high on the International Cleanup Conference agenda
It’s just four little letters, but anyone who lives near the RAAF base or a fire station may have cause to fear PFAS. And now, it’s going international.
SA News
Don't miss out on the headlines from SA News. Followed categories will be added to My News.
- PFAS soil cleaning trial at Edinburgh RAAF base
- Largs North residents warned to not eat garden produce
Chemical residues of substances made to resist heat, save lives and protect property have become public enemy No. 1 in many communities across Australia.
RAAF Base Edinburgh, Adelaide Airport and Largs North Fire Station are among the growing list of sites where past use of firefighting foam has come back to bite.
In these cases, PFAS — or per-fluoroalkyl and poly-fluoroalkyl substances — has soaked into the soil, leached into groundwater, and migrated offsite.
The persistent pollutants accumulate in the human body with unknown effects. While there’s “no consistent evidence” it causes cancer, many people are worried about their health, property prices and livelihoods.
When 700 delegates from more than 25 countries gathered in Adelaide for the International Cleanup Conference, PFAS was high on the agenda.
The conference is an initiative of the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment. It’s a collaborative venture that unites research and industry partners with a joint mission and Federal Government funding, which runs out on June 30.
Of all the contaminants, managing director Professor Ravi Naidu says PFAS is the one the majority of people wanted to hear about this year because it’s an “emerging contaminant” where there is so little information available and everyone wants to find out what’s new.
“The difference between PFAS and some of the other contaminants is incredible, when you are dealing with lead, or arsenic, you are dealing with a single contaminant,” he said.
“Whereas PFAS is a complex mixture of many different active ingredients and we do not know the impact that these different chemicals present in PFAS, what impact does it have on the environment or human health? We can say it is a mixture, it is doing something, it is having an adverse impact. When you have a complex situation like that, you cannot come up with a solution overnight.”
He says it’s important to remember PFAS was originally developed to protect people from fire, not to harm people or the environment. When it was introduced, nobody knew about the adverse impacts.
CLEAN-UP OPERATION
From the early 1970s until 2004, PFAS compounds were present in a type of firefighting foam used worldwide, called aqueous film forming foam, now banned from sale. PFAS contaminants have since been identified at more than 70 sites around Australia where fire training has been undertaken, plus sites where the substance was used for other purposes.
There are thousands of PFAS-contaminated sites in Australia, many of which have growing stockpiles of polluted soil and a lack of cost-effective methods to remediate them.
At the conference, CRC CARE launched its modified natural clay called matCARE to lock up PFAS in contaminated soil and water, reducing its ability to cause environmental harm.
Other approaches include thermal treatment, essentially incineration, which requires transport and energy-intensive high temperatures, or “soil washing” with solvents.
Adelaide company Ziltek has a product called RemBind, which binds permanently to contaminants. Since 2011, RemBind has been used commercially to treat a wide variety of contaminants, including PFAS. The product has been successfully applied in USA, Europe and Australia.
UniSA Associate Professor Albert Juhasz presented research on RemBind at the conference, using PFAS-contaminated soil from airports across Australia (but he won’t say which ones).
He showed how well the product worked to mop up the contaminant and also checked to see whether this made a difference to how much PFAS was available to living organisms (mice) when he mixed the soil into their food. Adding the soil amendment reduced the amount of PFAS taken up by the animal by more than 75 per cent.
Dr Juhasz says research in the area has “exploded” over the last couple of years since the Australian Research Council announced a Special Research Initiatives scheme for PFAS Remediation Research. Up to $13 million in funding was made available to facilitate the development of innovative technologies to investigate and remediate contaminated soil and other solid debris, groundwater, waterways and marine systems.
“They’re sort of putting the cart before the horse, saying let’s come up with some technologies to remediate this stuff, but we still don’t know whether there is any great risk associated with exposure,” Dr Juhasz said.
“There is some data, but there’s just not enough toxicological data out there to demonstrate that there are significant issues. That’s the state of the science at the moment and I suppose people have applied the precautionary principle, where they just want to make sure there is no issue … Whether that is a real risk or it’s just a perceived risk, I guess time will tell.”
An independent expert health panel established by the Federal Government has concluded there is mostly limited or in some cases no evidence, that human exposure to PFAS is linked with human disease.
Environment Protection Authority chief executive Tony Circelli says PFAS “obviously has been a very big issue internationally and also in Australia”, so the Commonwealth has developed a taskforce and recently released a PFAS National Environment Management Plan for
consultation.
FACING FEARS
He gave the opening plenary lecture at the Cleanup Conference entitled “From crisis to collaboration: the evolution of South Australia’s approach to managing legacy site contamination”, reflecting on how the EPA has learnt from experience, particularly the case of TCE contamination at Clovelly Park.
Mr Circelli referred to the work of international best-selling author, psychologist and winner of the Nobel prize in Economics, Daniel Kahneman.
In Thinking, Fast and Slow, Kahneman has an interesting chapter on emotion and risk that asks whether the public service should bother spending money in areas where there is no real scientific risk.
“If the community is going to have harm because of the emotional aspects of dealing with the unknown, then maybe there’s a reason a public purpose for spending funds to reassure and try and work with the community, to try and have a more balanced approach about what the harm and what the issues actually are,” Mr Circelli said.
“He concludes, with widespread fears, even if they are unreasonable, we shouldn’t ignore them as policymakers. Whether they are rational or not, fear is painful and debilitating, so he is urging policymakers to endeavour to protect the public from fear.”