NHMRC has published updated advice on per- and polyfluoroalkyl substances (PFAS) in the Australian Drinking Water Guidelines (the Guidelines), which includes new and revised guideline values for PFOA, PFOS, PFHxS and PFBS.
This update follows a comprehensive review of the latest evidence on PFAS in drinking water for the Australian context, including scientific reviews undertaken by other national and international agencies such as the United States Environmental Protection Agency (US EPA). It reflects Australia’s unique context, drawing on international advice while ensuring it aligns with our local health and safety standards. It is not unusual for guideline values to vary from country to country due to different risk assessment methodologies, calculations and the choice of health endpoints used. We do not automatically adopt overseas values without thorough review and adaptation to our conditions.
While the new guideline values are lower than those previously in place, that does not mean there is an immediate risk to your health if you drink tap water at the previous guideline values for short periods of time. The information available shows that most water supplies are already below the new guideline values, and we use cautious assumptions in setting these values, ensuring that even very small potential risks are addressed. Importantly, drinking water is only one of many sources for possible PFAS exposure, so higher values in drinking water for short periods is unlikely to increase health risks. As for all chemical guideline values, any detections of PFAS higher than the final guideline values should not be viewed as a pass/fail measure but should trigger an investigation of potential sources of contamination, in case these exceedances can be managed to bring the water supply back under guideline values.
NHMRC is responsible for producing the Australian Drinking Water Guidelines to ensure a consistent and robust approach to protecting public health across the country. Depending on the jurisdiction, States and Territories or water suppliers are responsible for determining how often water supplies are tested. These decisions are based on water catchment risk assessments, informed by water testing data. The existence of water supplies with higher PFAS levels cannot yet be ruled out. We suggest that water suppliers regularly share water testing results and information on the current risks in their catchment with their communities, including for PFAS. This transparency will assist in providing the public with reassurance about their drinking water.
The research on PFAS is ongoing, and NHMRC will continue to review and update the Guidelines as new evidence emerges. As it stands, the health risks from PFAS in drinking water are low for most Australians, and the revised health-based guideline values aim to further enhance the safety of drinking water supplies across the nation.
