New thresholds for PFAS in tap water; draft guidelines released

The National Health and Medical Research Council (NHMRC) has released updated draft Australian Drinking Water Guidelines for public consultation.

The guidelines provide health-based values for per- and polyfluoroalkyl substances (PFAS) in drinking water, and are said to be conservative, protective of human health and based on comprehensive evaluations of the latest evidence.

Part of the National Water Quality Management Strategy, the guidelines provide an authoritative reference to the Australian community, water regulators in the states and territories, and water suppliers on what defines safe, good-quality drinking water, how it can be achieved and how it can be assured.

“In Australia’s system for ensuring water is safe to drink, NHMRC is responsible for producing the Australian Drinking Water Guidelines. States and territories use these guidelines in regulating water utilities and suppliers. This applies a robust approach to protecting public health across Australia,” NHMRC CEO Professor Steve Wesselingh said.

No immediate changes or risks

The NSW Government welcomed the release of the new guidelines for public consultation, which recommend lower values for PFAS in drinking water across Australia. NSW Minister for Water Rose Jackson emphasised that all drinking water that meets the Australian Drinking Water Guidelines remains safe to drink.

“There are no immediate changes or risks when it comes to drinking water that meets our existing guidelines,” Jackson said.

“We understand the community’s concerns about PFAS and are committed to transparency, ensuring the community has access to up-to-date information.”

Sydney Water’s recent testing of the Blue Mountains’ water supply (Cascade Water Filtration Plant) confirmed that all samples from Sydney’s drinking water supply are well below the Australian Drinking Water Guidelines.

“To ensure ongoing safety, Sydney Water employs a risk-based approach to monitoring drinking water, and regular testing will continue in response to community,” Sydney Water said in a statement.

The NHMRC suggested that any detection of PFAS higher than the proposed new guideline values should not be viewed as a pass/fail measure but should be investigated and actions taken to bring the supply within the guideline values, the NSW Government said in a statement.

“NHMRC suggests that water suppliers regularly share information with the community on the current risks from PFAS in their catchment and the findings from background testing. This transparency will assist in providing consumers with reassurance about the water coming out of their taps,” Wesselingh said.

The public consultation advice suggests that based on human health considerations, the concentration of the following PFAS in drinking water should not exceed the specified health-based guideline values. The proposed guideline values are intended to reduce risks to health from PFAS in drinking water over a lifetime, not short periods of time:

• PFOA — The health-based guideline value is proposed to be lowered from 560 ng/L to 200 ng/L based on new health concerns (cancer effects).
• PFOS — The health-based guideline value is proposed to be lowered from 70 ng/L to 4 ng/L based on new health concerns (bone marrow effects).
• PFHxS — A new, separate health-based guideline value for PFHxS of 30 ng/L is proposed, based on thyroid effects.
• PFBS — A new, separate health-based guideline value for PFBS of 1000 ng/L is proposed, based on thyroid effects.
• GenX chemicals — A health-based guideline value for GenX chemicals could not be set at this time due to a lack of data.

Australian guidelines — less stringent?

Professor Denis O’Carroll, Managing Director of the UNSW Water Research Laboratory, said, “International organisations (eg, the European Union and the US Centers for Disease Control) have serious health concerns about a much wider range of PFAS than those subject to Australian guidelines.

“These new proposed drinking water guidelines for Australia are much less stringent than those of the European Union, the United States and Canada.

“The new Australian drinking water guidelines do not include all PFAS on the Stockholm Convention list, which are in place for the protection of human health and the environment from persistent organic pollutants (POPs).

“In a study led by UNSW earlier this year and published in Nature Geoscience, we found that PFAS levels in ... [much] of our international drinking source water exceeds drinking water guidance levels and that international guidance is much more stringent than Australia.”

More work required

O’Carroll said much more work is required to map out PFAS contamination in Australian source waters, and the government urgently needs to take a range of actions.

“These include funding research to better understand the health and ecosystem risks posed by a wide range of PFAS; improve our understanding of the environmental fate of PFAS; and develop cost-effective PFAS drinking water technologies,” he said.

“PFAS constitute a class of over 14,000 chemicals that have been extensively used in industrial applications and consumer products around the world and are a serious health concern.

“For example, the World Health Organization lists perfluorooctanoic acid (PFOA) as a Group 1 carcinogen and perfluorooctane sulfonic acid (PFOS) as a Group 2B carcinogen.

“The Australian Government should consider inclusion of a wider range of PFAS in the drinking water guidelines, as is common in a number of other countries.”

Water Services Association of Australia (WSAA) Executive Director Adam Lovell, “We support the ongoing review of these guidelines to ensure they are based on the latest science and methods for the Australian context, to help maintain high-quality drinking water across the country.

“The NHMRC members are the experts in their fields. They are advised by our top independent health, epidemiology and toxicology experts.

“The most important message is that consumers can have confidence in their drinking water — as the NHMRC advised, the risk from PFAS in drinking water is low for most Australians; your water is safe if it meets the guidelines.

“The water sector supports the NHMRC review and public consultation process. WSAA and its members will undertake a thorough review of the draft guidelines and provide any feedback, including on how they can be best implemented,” Lovell said.

Feedback sought

Oliver Jones, Professor of Chemistry and Deputy Director of the RMIT Water: Effective Technologies and Tools (WETT) Research Centre, said, “Much public concern about PFAS comes from emotive films like Dark Waters and documentaries like How to Poison a Planet. However, emotion is not science. Neither are clicks and likes or online influencers. Science is based on testable hypotheses, good data and evidence-based assessment. What the NHMRC have done here is a mostly good application of these principles.

“I am sure some will assume that since the guidelines are not at 0 ng/L — which is an impossible ask — they must have been influenced by ‘big chemical’. But remember that the people who set the guidelines also have to drink the water, as do their families. It’s not logical to assume they would set levels they thought were unsafe.

“I think the NHMRC have done a pretty good job here, but if people don’t agree, I’d encourage them to provide feedback and make their case to the NHMRC as part of the consultation,” Jones concluded.

Image credit: iStock.com/show999