As Australia's leading experts on health and medical research, NHMRC develops evidence based advice on priority health topics to prevent disease, improve health and help the states and territories to achieve consistent standards.
NHMRC has published updated advice on per- and polyfluoroalkyl substances (PFAS) in the Australian Drinking Water Guidelines (the Guidelines).
PFAS are human made chemicals that make products resistant to heat, stains, grease, and water. Because of their widespread use, almost everyone will have some exposure to PFAS in their lifetime.
The Guidelines include revised health-based guideline values for:
- perfluorooctane sulfonic acid (PFOS) - 8 nanograms per litre
- perfluorooctanoic acid (PFOA) - 200 nanograms per litre
- perfluorohexane sulfonic acid (PFHxS) - 30 nanograms per litre
- perfluorobutane sulfonic acid (PFBS) - 1000 nanograms per litre.
The final values are the same as those proposed at public consultation, except for PFOS where the final guideline value has been revised from 4 ng/L to 8 ng/L. This is based on the selection of a more robust benchmark dose model advised by NHMRC's Water Quality Advisory Committee, following consultation comments. By comparison, the previous value was 70 ng/L (shared with PFHxS).
This update is the result of a comprehensive review of the latest scientific evidence on PFAS in drinking water for the Australian context, including both national and international scientific reviews. Comments received during the public consultation conducted in October 2024 have been carefully considered, and a further round of expert review and targeted consultation undertaken.
The Guidelines are used by States and Territories to regulate safe drinking water. Jurisdictions will now determine the timelines for which water providers will be expected to meet the new values.
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.
As it stands, the health risks from PFAS in drinking water is low for most Australians. The information available shows that most water supplies are already below the new, lower guideline values, and these values are based on minimising risk over a lifetime's worth of exposure. NHMRC uses conservative assumptions in setting these values, and drinking water is only one of many sources of possible PFAS exposure.
NHMRC is responsible for producing the Guidelines to ensure a consistent and robust approach to protecting public health across the country. The Guidelines provide an authoritative reference to the Australian community, state and territory water regulators and water suppliers on what defines safe, good quality drinking water, how it can be achieved, and how it can be assured.
