Per- and poly-fluoroalkyl substances (PFASs) are often regarded an ‘emerging issue’ for water utilities and operators, however with the recent detections across the country in drinking water, ground water, the environment, food products and even livestock, the issue has well and truly ‘emerged’.
PFAS is in the news daily, and for communities with detections in their water supplies, or close to water sources, it can lead to loss of confidence in the safety of drinking water and fear of unknown impacts. For the water industry, our goal is to supply safe drinking water, and we must accept that this is an issue that is not going away and must be addressed.
What's the latest?
A very quick google search reveals frightening headlines about PFAS, its extent and potential health impacts:
(27 June 2018) Queensland's ban on PFAS firefighting foam questioned by professor (link)
(22 June 2018) Report into toxic chemicals finds PFAS worse than thought (link)
(26 June 2018) Toxic chemical PFAS found in livestock no cause for alarm, Victoria's chief vet says (link)
(27 June 2018) NSW can’t ban toxic PFAS chemicals, says Environment Minister (link)
(24 June 2018) Groundwater beneath Perth Airport heavily contaminated with PFAS (link)
(15 June 2018) Toxic Secrets: The town that 3M built - where kids are dying of cancer (link)
Where does PFAS come from?
It is common to hear that PFAS is not an issue due to the lack of sources. It is a misconception that PFAS is only an issue in areas near an airport or Airforce Base. There are a wide range of sources of PFAS.
The US Interstate Technology and Regulatory Council (ITRC) has prepared a fact sheet on the history and use of PFAS. Sources can include:
Production and Manufacturing Facilities – Textiles; leather; paper and paper products; metal plating and etching; wire manufacturing; production and use of industrial surfactants, resins, moulds and plastics; photolithography, semiconductor industry.
Fire-Fighting Foams- Firefighting foams are a complex mixture of both known and unidentified PFAS of differing molecular structures present in varying proportions
Landfills and waste disposal- Leachate from some municipal solid waste landfills has been shown to be a source of PFAS release to the environment;
Wastewater treatment- Consumer and industrial use of PFAS-containing materials, including disposal of landfill leachate and firefighting foam, results in the discharge of PFAS to WWTPs. WWTPs, particularly those that receive industrial wastewater, are possible sources of PFAS release
Biosolids - PFAS (measured as perfluoroalkyl carboxylic acids (PFCA) and perfluoroalkyl sulfonic acids (PFSA)) have been found in domestic sewage sludge
Commercial and Consumer Products Containing PFAS- paper and packaging; clothing and carpets; outdoor textiles and sporting equipment; ski and snowboard waxes; non-stick cookware; cleaning agents and fabric softeners; polishes and waxes, and latex paints; pesticides and herbicides; hydraulic fluids; windshield wipers; paints, varnishes, dyes, and inks; adhesives; medical products; personal care products (for example, shampoo, hair conditioners, sunscreen, cosmetics, toothpaste, dental floss).
Unknown – as sampling increases, more sources are likely to be identified.
PFAS are very stable and break down very slowly in the environment under naturally occurring conditions, therefore they tend to accumulate in the food chain and in human tissue. They can also bioaccumulate and biomagnify in some wildlife, including fish.
There is no consistent evidence on the health effects of PFAS, however the International Agency for Cancer Research has classified perfluorooctanoic acid (PFOA) as possible carcinogen (Class 2B). Perfluorooctane sulfonate (PFOS) has not been classified as yet. Monash University has prepared a literature review on potential health effects and recent studies into the human health effects.
What do we need to do?
The first step is understanding the level of risk. This should include understanding all potential sources in the study area and testing to quantify the level of risk.
Sampling processes
There are Standard Methods for analytical testing for the range of PFAS, PFOS and PFOA. For sample collection, the Australian Defence Force describes the following processes that are consistent with relevant Australian standards and the National Environment Protection (Assessment of Site Contamination) Measure framework to ensure the accuracy of samples:
laboratory-supplied sample containers are prepared and labelled
a fresh pair of nitrile gloves are used by the field staff member taking the sample
the sample is immediately placed in a cooler, and
re-useable sampling equipment is cleaned between each location and each sample collection.
The PFAS National Environmental Management Plan (NEMP) (January 2018) also provide the following guidance for drinking water samples:
For drinking water, each 250 mL sample bottle may be required to contain a small amount (1.25 g) of Trizma®, a buffering reagent that removes free chlorine from chlorinated drinking water (USEPA, 2009), or similar sample additive as specified by the selected analytical laboratory. Prior to sampling drinking water for PFAS analysis, confirm the need for additive with the selected analytical laboratory.
What is a good result, and what is a bad result?
In June 2016, the Department of Health commissioned Food Standards Australia New Zealand (FSANZ) to develop final health based guidance values for PFOS, PFOA and perfluorohexane sulfonate (PFHxS).
To determine the drinking and recreational water quality values for site investigations across Australia, the Department of Health used the final tolerable daily intakes for PFOS and PFOA and the methodology described in Chapter 6.3.3 of the National Health and Medical Research Council’s Australian Drinking Water Guidelines. (link)
Any values greater that the tolerable daily intake values below must be reported to the regulator.
What do to next?
The PFAS NEMP identifies a range of future work that is needed to further detail the actions that must be taken to manage the risk of PFAS.
First step is investigation - understand the risk for your water supply and quantify it with monitoring. Prioritise sites with a potential high risk source, or with sensitive receptors.
Working closely with health regulators on managing any detections.
Research options for prevention, treatment, destruction, immobilisation and encapsulation.
Implement strategies outlined in updates to ADWG, factsheets, the NEMP and subsequent publications.