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What you need to know about carcinogenic PFAS in tap water

Here's everything you need to know.

The safety of Australian tap water has been called into concern after a Sydney Morning Herald report was released assessing the level of PFAS (Per- and polyfluoroalkyl substances) which are carcinogenic chemicals found in drinking water across the country.

The report emerged off the back of the United States Environmental Protection Agency announcement in April where they affirmed that there was no safe level of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) found in drinking water.

The EPA also announced new standards which stipulate that the maximum limits of PFOA and PFOS should be 4 parts per trillion (ppt), which is the lowest amount that can feasibly be detected.

“The US EPA recommends no PFAS levels in the water but that’s aspirational,” explains UNSW Professor Denis O’Carroll. “4 parts per trillion for PFOS and PFOA, that’s what we can reasonably measure in a lab, it’s much harder to measure lower levels.”

Alarmingly, Australia’s current water standards allow PFOS at a 70 parts per trillion rate and PFOA at 560. According to federal data, a handful of suburbs across Australia now exceed the new US safety thresholds.

Here’s what you need to know.

Concerns over the amount of PFAS in our drinking water has been raised after the United States’ EPA declared there was no safe amount of the chemical in tap water.

What are PFAS, PFOS and PFOA? 

PFAS, which stands for per- and polyfluoroalkyl substances, is a term that you may be hearing increasingly in health, wellness and sustainability circles. PFAS has largely been come to known as ‘forever chemicals’ because of their ability to stay in the body and environment for many years. It’s an umbrella term that houses many other dangerous chemicals and known carcinogens such as PFOS and PFOA.

“PFAS are a group of chemicals that we use in a very wide range of our lives,” explains Profesor O’Carroll, who is also the Managing Director of UNSW’s Water Research Laboratory. “It’s used in cookware, it’s used in stain resistance, for water-repellency and historically it’s also found in firefighting foam. It’s really quite powerful.”

Since the 1950’s, PFAS have been found in many commercial products but it’s only been the last 30 years that we’ve discovered the seriously harmful effects of the chemicals.

“The dangerousness of PFAS is really an ongoing question, about 25 years ago, as a scientific community we became increasingly concerned about the health ramifications of PFAS. The ongoing debate is about how much exposure to the chemical is a bad amount to be exposed to.”

PFOA, which is the most notorious and well-studied PFAS, was first classified in 2014 as a possible human carcinogen. Just last year in 2023, PFOA was upgraded to a group 1 human carcinogen with WHO advising there is no safe level of exposure.

How do PFAS end up in drinking water?

Whilst the presence of PFAS are ubiquitous across the world, there are differing methods of exposure to these chemicals. For example, some industrial works and firefighters are at risk of occupational exposure. Meanwhile, the general population is exposed to PFOA and PFAS through food and drinking water.

“There’s a range of potential sources where PFAS can enter drinking water such as areas where metal plating or landfills for example exist,” Professor O’Carroll tells The Weekly.

In Richmond, which sits along the Hawkesbury on the outskirts of Sydney, alarming levels of 5.7 PFOS ppt and 3.8 PFOA ppt were found in the water in the 2011 study. 

After concern from the Richmond community, a 2018 investigation into PFAS contamination found a 10-square-kilometre plume of the chemical in groundwater. The contamination was declared to be a result of the use of legacy firefighting foam at the nearby Royal Australian Air Force base, which was phased-out in 2004.

Professor O’Carroll said that whilst in the 2011 report, North Richmond’s PFAS concentration was concerning, its more recent reports by Sydney Water are more promising and whilst it doesn’t meet the new US guidelines, it does meet water standards from Canada and Europe. 

“So in 2011 when the study was published, none of those locations would have been subject to any sort of oversight in the world. With time, a broader range of PFAS are being regulated and the level of exposure that has been deemed acceptable is increasingly changing.”

“All different countries quantify and calculate risks differently which is why for example, acceptable PFAS levels differ from Australia to the US to Europe.”

If this is true, then why does Australia compare its water to standards from other countries? Dr. O’Carroll explains.

“If somewhere is more restrictive with what’s acceptable, then we might look at those guidelines and ask ‘why is theirs lower?’ and ‘how does the concentration of our water compare to other standards?’”

Carcinogenic PFAS can enter drinking water supplies in a number of ways. Getty.

So, is it safe to drink tap water?

In light of the Sydney Morning Herald’s investigation, which was released on June 11, Australians turned to the government and water authorities for answers and clarification on whether it was indeed safe to consume the tap water. 

“We want to apply the best practice to Sydney Water, but the latest advice I have is that Sydney’s water is good,” NSW premier Chris Minns told radio 2GB in response to the investigation.

NSW Health Minister Ryan Park echoed these sentiments in a press conference that same day saying:

“We’re very fortunate that we have catchments that are largely protected … but it is something we monitor frequently,” Park said, as per Sydney Morning Herald. “My kids drank water out of the tap in the Illawarra this morning … they’ll be drinking it today at school, they’ll be drinking it when they get home.”

“It’s complicated,” Professor O’Carroll tells The Weekly. “Personally, I drink tap water and I have no reservations.”

Not only is there concern over Australia’s vastly differing PFAS water standards in comparison with the US, but alarm bells have also been raised over how little nationwide testing is done on our drinking water.

It appears that since the 2011 University of Queensland study, there have been no further widespread investigation of Australian tap water funded by Commonwealth agencies. 

The only site where Sydney Water tests for PFAS contamination is in North Richmond and the agency’s website states: “We are not currently monitoring drinking water supplies for PFAS except at North Richmond.”

Whilst Sydney Water also affirmed to The Weekly that “there are no known PFAS hotspots in our drinking water catchments,” it is unclear what data is used to measure what qualifies a location to be a PFAS hotspot how that compares to the new United States guidelines.

The Australian Women’s Weekly also reached out to NSW Health for further information but they declined to comment.

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