The best-supported household option is generally a properly selected, independently verified and maintained under-sink reverse osmosis system. It can reduce a broad range of PFAS, but performance varies by model and no unit should be assumed to remove every PFAS completely.
Before buying a filter, check Sydney Water’s latest published water-quality information to determine whether PFAS treatment is relevant to your supply. Boiling does not remove PFAS and may increase their concentration as water evaporates.
How the filtration options compare
- Reverse osmosis: Generally provides the broadest household PFAS reduction. It uses a membrane and discharges rejected contaminants in a wastewater stream. Performance depends on the complete system, water conditions and maintenance.
- Granular activated carbon: Adsorbs PFAS onto carbon media. Its effectiveness depends on the carbon, contact time, cartridge capacity and PFAS present; some short-chain PFAS can be harder to capture.
- Ion exchange: Uses specialised resin to capture PFAS. Results depend on the resin, flow rate, water chemistry and replacement schedule, so model-specific evidence is essential.
These systems reduce rather than destroy PFAS. Reverse osmosis transfers them to reject water, while carbon and ion-exchange filters retain them in spent media.
What to check before choosing a filter
Choose the exact model based on credible performance evidence, not a generic claim about carbon, resin or reverse osmosis.
Check:
- independent certification or credible laboratory testing for the exact model;
- which PFAS were tested and under what conditions;
- whether the evidence covers only PFOA and PFOS or a broader PFAS group;
- the tested reduction and rated cartridge or membrane capacity;
- replacement, flushing and sanitising requirements;
- treated-water flow, storage capacity and reverse osmosis wastewater production;
- required water pressure; and
- ongoing cartridge, membrane and servicing costs.
Verify any certification claim in the certifying body’s current product database and read its scope. Certification for selected compounds does not establish reduction of every PFAS.
Installation, maintenance and disposal
Replace cartridges and membranes at the manufacturer’s specified intervals. Overdue carbon or resin media may no longer deliver its tested performance.
Under-sink plumbing contains pressurised water, and incorrect work can cause leaks or water damage. You can check for leaks and isolate the water supply, but any regulated plumbing connection or alteration should be completed by an appropriately licensed NSW plumber.
Spent media may contain captured PFAS. Follow the manufacturer’s take-back or disposal instructions and check current advice from your council or the NSW EPA rather than assuming it belongs in household waste.
For help selecting and installing a suitable system, contact our Sydney plumbing team.