- →The June 2025 ADWG update sets substantially lower individual health guideline values for specific PFAS compounds, following IARC's 2024 Group 1 carcinogen classification of PFOA.
- ✓Most Australian capital city scheme supplies already met the new limits — Sydney, Melbourne, Brisbane, Adelaide and Perth all confirmed compliance without additional treatment.
- !Blue Mountains (Cascade zone): had elevated PFAS. Sydney Water installed GAC treatment December 2024. The zone now meets the updated June 2025 limits.
- →The IARC Group 1 classification relates to occupational and industrial exposures — not to well-managed drinking water at ADWG-compliant concentrations. The update reflects improved evidence, not a sudden new danger.
- ✓Filter recommendation unchanged: NSF 58 certified RO removes 90–96% of PFAS and remains the most defensible household option for those seeking additional protection.
What changed in June 2025
Australia's drinking water health guidelines for PFAS were substantially lowered in the June 2025 update to the Australian Drinking Water Guidelines (ADWG), published by the National Health and Medical Research Council (NHMRC). The update was driven by accumulating health evidence — most significantly the June 2024 IARC classification of PFOA as a Group 1 carcinogen (sufficient evidence of carcinogenicity in humans) and PFOS as Group 2B (possibly carcinogenic).
The previous ADWG had a single combined guideline value for PFAS. The June 2025 update sets individual health guideline values for specific PFAS compounds at concentrations substantially lower than the previous single limit. Specific values are published at the NHMRC website.
What it means for your tap water
All major Australian water utilities were required to assess their supplies against the new limits. The key outcomes:
- Most Australian capital city supplies: Already met the new limits without additional treatment. Sydney, Melbourne, Brisbane (Seqwater), Adelaide (SA Water) and Perth (Water Corporation) all confirmed compliance.
- Blue Mountains (Sydney Cascade catchment): This zone had PFAS detected in June 2024 at concentrations that exceeded the new June 2025 limits. Sydney Water installed GAC (Granular Activated Carbon) treatment at Cascade Water Filtration Plant in December 2024. The Cascade zone now meets the updated limits.
- Areas near defence bases: Investigations are ongoing. Scheme supplies in areas near RAAF bases have been tested — scheme supply meets ADWG limits. Bore water in affected areas remains a separate concern.
The June 2025 ADWG update does not mean your tap water was previously unsafe — the previous guidelines were set with large safety margins. The update reflects improved epidemiological evidence and application of the precautionary principle. Drinking well-below-guideline water over many years does not produce the health outcomes associated with higher industrial exposures.
What the IARC Group 1 classification means
IARC Group 1 means there is sufficient evidence of carcinogenicity in humans — the highest classification, shared with compounds like tobacco smoke and asbestos. For PFOA specifically, epidemiological studies have shown associations with kidney cancer and testicular cancer at occupationally or industrially elevated exposures.
Importantly, the IARC classification is about weight of evidence, not about exposure levels in drinking water. Industrial workers and people living near PFOA manufacturing plants face exposures many orders of magnitude higher than anyone drinking well-managed tap water. The ADWG health guideline is set to produce negligible risk at the guideline concentration — the new lower limits reflect updated risk modelling.
Filter recommendation update
The June 2025 ADWG update does not change which household filters are effective against PFAS. The technology picture is unchanged:
- NSF 58 certified reverse osmosis: Removes 90–96% of PFAS. Verified performance against specific PFAS compounds. The most comprehensive and well-evidenced household option. A countertop RO needs no plumbing and is appropriate for renters.
- NSF 58 certified RO with specific PFAS claim: Some RO systems now specifically list PFAS reduction percentages on their NSF 58 certificate — worth looking for as testing becomes more widespread.
- Carbon block filtration: Provides partial PFAS reduction at the scale used in treatment plants (large GAC columns with long contact time). Household carbon block cartridges are not the same as utility-scale GAC treatment and should not be assumed to provide equivalent PFAS reduction.
For households in areas meeting ADWG limits: no filter change is needed on safety grounds. For households seeking additional peace of mind or those near known PFAS sites: NSF 58 RO remains the most defensible household option.
What to do now
For most Australian households: nothing immediate. Check your utility's published PFAS testing data for your supply zone — all major utilities publish this now. If your zone meets the June 2025 ADWG limits (which most do), your scheme water is within the health guidelines.
If you are on bore water near a known PFAS contamination site: independently test with a NATA-accredited lab ($150–$400 for a PFAS panel). This is the only way to know the actual concentration in your water from your specific bore. See our PFAS affected areas guide for the status of known sites.
The update reflects improved health evidence following IARC's 2024 PFOA Group 1 classification. Blue Mountains (Cascade zone) required and received GAC treatment and now meets the new limits. All other major Australian capital city supplies were already compliant.
Filter recommendation: NSF 58 certified RO remains the gold standard for household PFAS reduction. The update does not change this. For most Australians on scheme water who are not near known contamination sites, no additional filter action is required on safety grounds.