High levels of so-called forever chemicals have been found in surface and groundwater all over the world, with Australia one of several hotspots for toxic PFAS, a University of New South Wales study has found.
Researchers examined groundwater samples from around the world and found 69% had per-and poly-fluoroalkyl substances (PFAS) at levels above Canada’s safe drinking water criteria and 32% had levels higher than the US proposed drinking water hazard index.
They found Australia was one of several “hotspots” relative to the rest of the world, along with China, Europe and North America.
More than 14,000 human-made chemicals are PFAS, including PFHxS, PFOS and PFOA. They have been used in firefighting foams, insecticides, food packaging, non-stick frypans, clothing and cosmetics. They were created for their high heat tolerance, and water and oil repellent properties.
They were dubbed forever chemicals because they do not break down in the environment or the human body. PFAS have been linked to cancers, thyroid disease, altered sex hormone levels, reduced kidney function and lower birth weight in babies, but have not been proven to cause these conditions.
The study author, engineering professor Denis O’Carroll, said Australia’s limit on acceptable PFOA in drinking water was “orders of magnitude” higher than in the US.
Australia’s PFOA limit is 560 nanograms per litre, while PFOS and PFHxS is limited to 70n/gl. Canada limits all PFAS to 30 ng/l, and the US limits PFOS and PFOA to four ng/l.
“Australia has much higher limits than the US, but the question is why,” O’Carroll said. “Both health bodies would have different reasoning for that, and there’s not a really strong consensus here.”
And we are “likely underestimating the environmental burden posed by PFAS”, he said. “There’s a real unknown amount of PFAS that we’re not measuring in the environment. Commercial products like garments and food packaging have a lot more PFAS in them than we realise.”
While surface and groundwater is usually filtered before it becomes drinking water, O’Carroll warned that some water providers – including Sydney Water – did not routinely measure PFAS in drinking water.
Sydney Water has said there is “no current evidence that PFAS is an issue”. It tested water in 2019 and 2023.
O’Carroll said drinking water was generally safe but should be monitored.
“The source water is the source of our drinking water, so we should be concerned about PFAS or other chemicals we put into the environment,” he said.
“For me, I drink water from the tap without hesitation, so I don’t worry about it. But I think we need to make sure we protect our source.”
The Australian government says most people are “very likely to have very low levels of PFAS in their bodies through exposure to everyday household items like carpet and upholstery protective sprays, cosmetics, sunscreens and some non-stick cookware”.
People who live near sites where PFAS has been released into the environment in large amounts may have higher levels, especially if they have been drinking contaminated bore water.
The government says studies of the potential health effects have had mixed results. Its PFAS expert health panel found that “although the scientific evidence in humans is limited, reviews and scientific research to date have provided fairly consistent reports of an association with several health effects”.
“The health effects reported in these associations are generally small and within normal ranges for the whole population,” the government’s statement says. “There is also limited to no evidence of human disease or other clinically significant harm resulting from PFAS exposure at this time.”
New Zealand plans to ban PFAS, while the European Union is phasing out their use. Some states in the US have restricted their use.
The Australian government has begun restricting PFAS use and plans to introduce new controls from 1 July next year so that PFOS, PFOA and PFHxS will be banned or severely restricted.
The study, the first to quantify PFAS in this way, was published in Nature Geoscience.
