PFAS Remediation

Well, the question is really “What are PFAS?” because PFAS are actually an entire group of chemicals. These man-made chemicals are used to produce various industrial and household products. Some common uses of PFAS are in waterproof clothing, non-stick cookware and fire-fighting foams.

PFAS stands for per- and polyfluoroalkyl substances, but they’re also known simply as the “forever chemicals,” because they don’t break down naturally. As a result of this, they have accumulated in water and soil around the world.   

PFAS are characterised by the presence of fluorinated carbon chains. There are numerous types of PFAS, each with its own chemical structure and properties. Some common types of PFAS include: 

Perfluorooctanoic acid (PFOA)

PFOA is a long-chain PFAS that has been used in the production of non-stick cookware, stain-resistant fabrics, and other consumer products. It has been associated with various health concerns and is subject to regulatory scrutiny and phase-out measures. 

Perfluorooctanesulfonic acid (PFOS)

PFOS is another long-chain PFAS that has been used in a variety of industrial and consumer applications, including firefighting foams, food packaging, and stain-resistant coatings. Like PFOA, PFOS is persistent in the environment and can accumulate in organisms. 

Perfluorohexanesulfonic acid (PFHxS)

PFHxS is a shorter-chain PFAS that has been used in similar applications as PFOS. It is also persistent and bioaccumulative, posing potential health and environmental risks. 

Perfluorobutanesulfonic acid (PFBS)

PFBS is a shorter-chain PFAS that has been used as a replacement for longer-chain compounds like PFOS and PFOA in certain applications. While it is less persistent in the environment compared to its longer-chain counterparts, PFBS still poses environmental and health concerns. 

Perfluorodecanoic acid (PFDA)

PFDA is a long-chain PFAS that has been used in various industrial applications, including as a surfactant and in the production of polymers. It is persistent and can bioaccumulate in organisms. 

These are just a few examples of the many types of PFAS that have been synthesised and used in commercial products and industrial processes. Due to their persistence, bioaccumulative nature, and potential health effects, there is growing concern and regulatory attention surrounding the use and environmental presence of PFAS. 

With a unique chemical design, PFAS were valued for their hydrophobic, hydrophillic, and lipophobic properties, traditionally manufactured by complex processes of electrochemical fluorination or fluorotelomeris. 

These properties allowed PFAS to be extremely resistant to heat, water and oil, making them useful in a wide range industrial processes, fire-fighting foams and consumer products. Some uses of PFAS include: 

• Non-stick cookware, such as Teflon 
  
  
• Stain- and water-repellant fabrics, carpets and upholstery 
  
  
• PFAS-based firefighting foams, also known as aqueous film-forming foams (AFFF) 
  
  
• Grease-resistant food packaging materials, including microwave popcorn bags, fast-food wrappers, and pizza boxes 
  
  
• Electronics such as semiconductors and capacitors, due to the insulating properties of PFAS 
  
  
• Medical devices like catheters and tubing, as well as certain pharmaceuticals, for their lubricating and surfactant properties. 

The chemical structure of PFAS defines the persistence and mobility, which, combined with decades of widespread application, has resulted in trace identification in environments across the globe.

With mounting evidence of the adverse environmental and health effects, the complexity of managing PFAS is reflected in the rapidly evolving regulatory landscape, both locally and internationally.  

Individual PFAS chemicals are sometimes regulated differently. Since 2009, PFOS has been included in the international Stockholm Convention for elimination, with PFOA being added in 2020 and PFHxS in 2022. While the manufacturing of PFAS chemicals is mostly banned or restricted, the utilisation and application of AFFF in catastrophic circumstances continues. 

Australia

Through initiatives like the National Environmental Management Plan (NEMP), Australia sets a commendable example with health-based guidance values applied country-wide, in continuity with EPA state requirements. 

The United States

In 2023, the United States Environmental Protection Agency (US EPA) proposed the establishment of legally enforceable drinking water levels for six PFAS species in accordance with its PFAS Strategic Roadmap. Despite these proposed health- based concentration limits, federal regulatory statues under Resource Conservation and Recovery (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) have yet to provide finalised regulation. As a result, standard and guidance values currently vary significantly from state to state. 

Europe

The European Chemical agency committed to implement EU chemical legislation has defined a 0.5ug/L drinking water directive under REACH in 2021. 

The concern surrounding PFAS is particularly high in areas with extensive use of aqueous film-forming foam (AFFF), as AFFF is a known source of PFAS. Locations such as airports and military bases, often utilised for firefighting training, become hotspots for PFAS contamination.  

The heightened usage of AFFF amplifies the risk of PFAS migration: the movement of PFAS from one contaminated substance or material to another. Migration commonly occurs when PFAS-containing materials come into contact with water, food, or other substances, causing the PFAS compounds to transfer or leach into the surrounding environment. 

This naturally raises substantial concerns about the potential impact on both environmental ecosystems and public health. Understanding these features is crucial for developing effective strategies to mitigate PFAS contamination risks. 

Yes. But it’s not easy, and some methods can create additional risks or adverse environmental impacts. 

PFAS contamination represents a global challenge, identified internationally in air, soil, groundwater, and surface water. Given its capacity to be readily transported long distances once in groundwater compared with other forms of contamination, a prompt, proactive response is critical.   

The stability and surfactant properties of PFAS, in combination with its extensive industrial adoption, have created a unique environmental remediation challenge. An increasingly stringent regulatory landscape, combined with social and environmental awareness, has resulted in a shift towards in-situ immobilisation, removal, and destruction in support of traditional and ex-situ PFAS technologies. 

With a focus on drinking water and groundwater, effective in-situ technologies can support the pragmatic risk-based combination of synergetic approaches required.   

The solutions that we offer at Photon Water in the remediation of surface water, groundwater and soil provide a sustainable alternative, reducing the contamination mass concentration directly onsite. Our solutions are powered by renewable energy, produce little to no waste, and work with naturogenic chemical materials.