What are PFAS?
PFAS are per- and polyfluoroalkyl substances, a group of over 4000 chemicals. Some PFAS are very effective at resisting heat, stains, grease and water, making them useful chemicals for a range of applications including:
- Stain and water protection for carpets, fabric, furniture and apparel
- Paper coating (including for some food packaging)
- Metal plating
- Photographic materials
- Aviation hydraulic fluid
- Cosmetics and sunscreen
- Medical devices.
Because they are heat resistant and film-forming in water, some PFAS have also been used as very effective ingredients in fire-fighting foams.
In Australia, the historical use of PFAS in fire-fighting foams has resulted in increased levels being detected at sites like airports, Defence bases, and other sites where fire-fighting training has been conducted, or where fire suppression systems are installed for extinguishing liquid-fuel fires. Increased environmental levels of PFAS have also been found near some industrial areas, effluent outfalls and landfill sites. Outside of these areas, it is unlikely that increased levels of PFAS would be present in the local environment.
Unfortunately, the properties that make some PFAS useful in many industrial applications and particularly in fire-fighting foams, also make them problematic in the environment. The PFAS of greatest concern are highly mobile in water, which means they travel long distances from their source-point; they do not fully break down naturally in the environment; and they are toxic to a range of animals.
While understanding about the human health effects of long-term PFAS exposure is still developing, there is global concern about the persistence and mobility of these chemicals in the environment. Many countries have discontinued, or are progressively phasing out, their use. The Australian Government has worked since 2002 to reduce the use of certain PFAS.