Cancer-linked “forever chemicals” have been found in drinking water sources at levels that exceed overseas guidelines, Sydney Water has confirmed.
Per- and polyfluorinated chemicals (PFAS) were detected at levels considered unsafe in the United States at key Sydney water filtration plants including Orchard Hills and Prospect in June.
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The highest levels were detected at Cascade Dam in Blackheath and Katoomba in the Blue Mountains.
The US Environmental Protection Agency (EPA) believes there is no safe level for two PFAS — perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) — in drinking water due to the health risks to humans.
PFAS exposure over a long period of time can cause cancer and other serious illnesses, the US EPA warns.
However, the Australian government guidelines outline there is a safe level of PFAS exposure.
Sydney Water said the samples tested for PFAS in June were below the limits specified by Australia’s drinking water guidelines.
The data, quietly released online, revealed the highest detection was at Katoomba where PFOS was found at 0.0164 micrograms per litre (µg/L) and another PFAS type, PFHxS, at 0.0142µg/L.
PFOS was also found at Blackheath at 0.0155µg/L and PFHxS at 0.0136 µg/L.
Low levels of PFAS were also found at Prospect Reservoir, Orchard Hills, Warragamba and North Richmond.
Under Australian drinking water guidelines, the safe level of PFAS is 0.07 µg/L combined for PFOS and PFHxS.
The US, which is seen as a world leader in PFAS regulation, recently set an enforceable threshold of 0.004 µg/L.
For decades, PFAS chemicals have been used to make products resistant to water, stains and heat.
They earned their name as “forever chemicals” as they do not naturally break down.
The chemicals have been deemed carcinogenic by the International Agency for Research on Cancer (IARC), and linked to various cancers, adverse reproductive and developmental outcomes, altered hormone production, altered immune and thyroid function, and liver and kidney disease.
Australian standards under review
Experts say PFAS are found in almost everything, making them near impossible to avoid.
Because of this, the government says most Australians are “likely to have very low levels of PFAS in their bodies”, but it claims these levels are not dangerous.
International Pollutants Elimination Network senior policy adviser Mariann Lloyd-Smith, who has 45 years’ experience working with PFAS and toxic chemicals, said Australia’s approach to PFAS monitoring was shameful.
“Our international colleagues just can’t believe it,” she told 7NEWS.com.au.
“They are astounded that Australia has taken such a lackadaisical attitude and that, after all the research we’ve got, the Australian government still claims there’s no evidence of harm from these chemicals.
“What makes Australian governments so reluctant to act and protect their communities? I don’t have an answer for that.”
Lloyd-Smith called for Australia to adopt the US standards, which were based on “some of the best science, with some of the most rigorous assessments”.
The Australian Drinking Water Guidelines, developed by the National Health and Medical Research Council (NHMRC), were last updated in 2018, but Lloyd-Smith said the evidence of harm related to PFAS was known to the government even then.
These guideline values are based on the tolerable daily amount of the chemicals deemed safe to consume according to Food Standards Australia New Zealand (FSANZ), the Department of Health told 7NEWS.com.au.
But those levels of human tolerance to PFAS are contested globally.
Australia’s “daily tolerable intake” is 280 times more than the amount deemed safe by the European Food Safety Authority (EFSA), Lloyd-Smith said.
The Australian standards are now under review, with advice from the NHMRC Water Quality Advisory Committee, “to determine whether the current NHMRC advice remains appropriate,” the Department of Health told 7NEWS.com.au.
It confirmed updated guidance is not expected until April 2025, following public consultation in October 2024.
Sydney Water has been contacted for comment.
