Per- and poly-fluoroalkyl substances (PFASs)
Per- and poly-fluoroalkyl substances (PFASs), commonly called PFAS or PFC, are a large group of man-made chemicals that includes perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). PFASs accumulate in the environment and the human body and do not readily breakdown. Exposure to high levels of PFASs may have adverse effects on human health. Due to widespread global contamination from these compounds, there is a corresponding widespread low level exposure among the general population in Australia and worldwide. This exposure has not been shown to cause health problems.
See below for frequently asked questions:
- What are PFASs?
- What are PFASs used for?
- Can PFASs enter the environment?
- How can people be exposed to PFASs?
- What are the effects of PFASs on health?
- Do PFASs cause cancer?
- What about exposure in pregnant women and children?
- Should I have a blood test to measure my exposure?
- What can I do to reduce my exposure?
- Further information
PFASs have been used in a variety of industrial, commercial and consumer products in Australia.
Chemically the perfluorinated compounds are impervious to heat, extremes of pH and UV light which conveys the property of being chemically inert, non-wetting, very slippery, non-stick, fire resistant and therefore environmentally stable.
PFASs repel oil, grease, and water and have been used since the 1950s in a range of common household products and speciality applications, including in the manufacture of non-stick cookware; fabric, leather, furniture and carpet stain protection applications; spot removers; food packaging; some industrial processes; and in some fire-fighting foams.
Due to the concerns about the environmental persistence of these chemicals, PFASs have been phased out from most uses since 2002.
The fluorinated hydrocarbons are referred to by a number of names. The commonly used terms for the perfluorinated hydrocarbons are:
- Perfluoro chemicals or compounds (PFC)
- Perfluoroalkyls substances (PFAS)
- Perfluorinated alkyl acids
- Polyfluorinated chemicals
- Polyfluorinated compounds
- Polyfluoroalkyl substances.
At present, PFASs can be used in metal plating industry, in hydraulic fluids in aviation and as surface treatments in some photography applications. Until recently, these chemicals were used in some types of firefighting foams. Some imported consumer products may still contain PFASs. While PFASs may be used in the manufacture of non-stick cookware in Australia, these chemicals are not present in the finished products.
PFASs are not manufactured in Australia, but they can be imported into Australia. Since 2002, the National Industrial Chemicals Notification and Assessment Scheme (NICNAS) restricted the importation and use of PFASs to only essential uses for which no suitable safer alternatives are available.
PFASs have been released into the environment through the use of firefighting foams, in accidental releases on industrial and landfill sites, and through waste disposal of products containing the chemical. These chemicals are now widespread global contaminants which are likely to remain in soil and water for many decades.
PFASs do not breakdown in the environment and can travel long distances in water and air currents. They can also bioaccumulate in wildlife, including aquatic animals, which means that animals that consume other animals accumulate the chemical in their tissues.
The exposure in the general public, although likely to be widespread, is well below the health concern levels for most populations.
PFASs can be ingested with contaminated food and water, and inhaled with water aerosols when contaminated water is used for purposes such as showering or watering the garden.
Fish consumption is believed to be the main source of exposure among the general public. PFASs are commonly detected in fish, other seafood and meat products. These chemicals can also be present in groundwater and surface water and may find their way into drinking water supplies in highly contaminated areas.
Carpets and floors treated with PFASs-containing surface preparations can be a source of exposure for young children.
Using borewater contaminated with PFASs for domestic purposes, such as drinking, cooking, showering, and watering edible plants, could potentially lead to significant exposure.
The effects of PFASs exposure on humans are largely unknown, although there may be a concern for human health if exposure levels are high. Most of the research in this area has been done in laboratory animals at higher levels of exposure than found in people.
Some studies in human populations exposed to unusually high levels of PFASs, such as in occupational groups or communities living on contaminated sites, have shown association with higher cholesterol levels, liver changes, heart disease, and hormonal changes. The reports of these associations are inconsistent and contradictory.
The precautionary approach is to consider that there may be potential for adverse health effects at high exposure levels.
There is no conclusive evidence to suggest that PFASs have carcinogenic potential at levels usually encountered. Studies in exposed workers have not shown an increase in cancers. Research in laboratory animals showed association with some types of cancer during long-term high-level exposure studies. It is not clear if the biological mechanisms observed in laboratory animals are relevant to humans.
The International Agency for Cancer Research (IARC) classified PFOA as possibly causing some cancers, although there is no agreement on this among the wider scientific community.
Some studies detected PFASs in samples of cord blood, meconium and amniotic fluid in women exposed to high levels of PFASs (PFASs industry workers). PFASs have also been found in breast milk samples. This shows that a portion of PFASs absorbed by the mother can reach the child. The detection of PFASs has not been associated with adverse outcomes in newborns and young children.
Children take up more chemicals than do adults under the same conditions. Also, children’s developing bodies may react differently to the same exposure levels. It is for these reasons that scientists take a precautionary approach when assessing the potential for negative health effects of chemical exposures in children.
Despite extensive research, there is no evidence that exposure to PFASs during childhood may have life-long adverse health effects.
PFASs are commonly detected in blood samples in the general population. In some studies 99.9% of the population were found to be exposed to these chemicals sometime in their life.
It is not clear what the detection of PFASs in your blood sample would mean for your health. Given that the understanding of human health effects is extremely limited, meaningful interpretation of an individual blood sample result is unlikely. The PFASs blood test results will not help your medical practitioner to make clinical decisions about your health care.
Your results may be compared to the average population results to see whether you have been exposed to unusually high levels of PFASs. Repeat measurements in a community known to be exposed to higher levels of PFASs can help to evaluate whether exposure reduction measures are working.
PFASs are widely present in the everyday environment. It is likely that you are exposed to low levels of PFASs every day without any known risks to your health.
While PFASs are known to be present in food, it is unlikely that limiting your intake of a particular food group will make a significant difference in your exposure levels. It can, however, be unwise from a nutrition point of view.
Of highest concern would be exposure though contaminated borewater if used for domestic purposes, such as drinking, cooking, showering, watering edible plants. The Department for Health and Ageing has advised South Australians that borewater needs to be tested for the presence of chemical and microbiological contaminants in order to be deemed safe for its intended use. That means borewater should not be used for domestic purposes unless it has been tested and the tests demonstrate it to be safe.
It is recommended that communities living close to sites where significant levels of contamination with PFASs have been detected should take measures to reduce their potential exposure. The exposure reduction measures need to be developed on a case-by-case basis.
For further information on PFASs, contact SA Health’s Scientific Services on
(08) 226 7100, or visit the Interim national guidance on human health reference values for per- and poly-fluoroalkyl substances for use in site investigations in Australia.