Many contamination issues arising from the industrial legacy of the UK are well documented and understood, however, new risks from some well-established chemicals and compounds are continuing to be identified, adding to the total chemical burden on the population and ecosystems. Recently, PFAS have been making headlines, but what are they, where do they come from and why do we need to be aware of them?

What are PFAS?

PFAS (per- and polyfluoroalkyl substances) are a complex family of manmade chemicals that have been produced since the first half of the 20thcentury. It has been estimated that the PFAS family may include approximately 5,000 to 10,000 chemicals.  

Development and use of these chemicals increased after a deadly fire aboard a U.S. Navy aircraft carrier, the USS Forrestal in 1967. The fire resulted from the accidental firing of a rocket into armed, stationary aircraft with loaded fuel tanks. Water was ineffective against the fire and served only to mobilise the jet fuel, which is less dense than the water, and spread the burning fuel across the deck of the ship. The blaze nearly destroyed the ship and resulted in the death of more than 130 people.

Soon after the tragic incident, manufacturers and scientists developed PFAS-containing aqueous film-forming foam (AFFF). When applied to a hazard, AFFF produces an aqueous film that spreads across the surface of the burning fuel to smother and extinguish the flame. This film is what gives AFFF its name, and it works by suppressing flammable liquid vapour, effectively suffocating the fire hazard. PFAS-containing AFFF was subsequently adopted for use as a fire suppressant on military and civilian ships, industrial facilities, airbases and airports.

As well as a fire suppressant, the unique physical and chemical properties of PFAS provided multiple beneficial properties such as repelling oil and water, high thermal stability and surface tension effects, which has led to the development and manufacture of more and more PFAS containing products.

These beneficial properties have led to a wide range of uses, from water and stain-resistant treatments for textiles and building materials, to cosmetics, non-stick cookware but, most notably, the foam used in firefighting. Therefore, their presence in our human and natural environment is prolific, whether through everyday usage of products containing PFAS, seepage from landfill sites, industrial accidents or deliberate dumping of industrial waste.

An overview of the timeline charting the invention, production and use of PFAS compounds is illustrated in the following table.

What are the impacts of PFAS?

Initial scientific studies into the impacts of PFAS have focused on perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) and have identified that they do not appear to biodegrade, making them extremely persistent and allowing for bioaccumulation and biomagnification in humans, animals and the environment. As a result, they are sometimes referred to as ‘forever chemicals’ because of their extreme persistence.

Common Sources of PFAS contamination

Consumer products such as non-stick pans, cosmetics, water proof clothing, furniture, carpeting, grease-proof paper and cardboard fast-food packaging can contain PFAS compounds. The chemicals are also widely used in commercial applications like wiring insulation, personal protective equipment, and medical devices. Where PFAS containing products reach the end of their active life, they may find their way into landfills as waste. Where PFAS waste leaches from landfills, and the leachate is allowed to migrate it has the potential to enter the wider environment, including surface water, groundwater, soils, wildlife populations, the food chain and ultimately accumulating in humans.

Furthermore, the effectiveness of AFFF as a fire suppressant has led to its widespread use at civilian airports, MOD sites, fuel storage sites and sites installed with fire suppressant foam sprinkler systems. A particular release of note in the UK is the Buncefield Oil Terminal fire in December 2005. An explosion ripped through the oil depot, thought to be the biggest peacetime explosion in the UK, being heard 125 miles away and measuring 2.4 on the Richter scale. The subsequent blaze took three days to put out, with the plumes of smoke large enough to be seen from space. While most of the fuel burned away, there were concerns that the indiscriminate manor in which the foam was applied to the fire by the emergency services would enable AFFF to migrate across a wide area and infiltrate sensitive ecosystems.  

What Risks Do PFAS Pose?

No PFAS was recorded to be present in natural environments prior to the 1940’s; however, post 1940, when they were first developed and were widely used, they have been detected across the globe within wildlife and aquatic systems and within human blood and tissue. Due to the persistent nature of PFAS chemicals they have the potential to bioaccumulate and bio-magnify in the food chain. In humans and wildlife, PFAS has been linked to multiple health problems, including the development of certain diseases (e.g. kidney and testicular cancer).

For Controlled Waters, PFAS’ extreme persistence, high solubility and mobility, coupled with the fact that many standard remediation strategies are largely ineffective, means that they could have widespread low-level distribution in ground and surface waters. When in groundwater, they can produce contamination plumes multiple kilometres in length, with the potential to impact groundwater wells and other receptors over a large area.

PFAS Regulation

PFAS regulation differs significantly from region to region across the world, although there are increasingly more organisations calling for a partial or complete ban of PFAS as the potential liabilities to health and the environment become more apparent.

UK non-governmental health and environmental organisations are calling on the UK Government to implement stricter regulation and even ban the use of some PFAS compounds to protect the UK environment from what are claimed to be the most persistent human-made chemicals known to date. In response, the UK, Welsh and Scottish Governments tasked the Health and Safety Executive (HSE) and Environment Agency in 2021 to form a Regulatory Management Options Analysis (RMOA) on PFAS, to assess how to best manage any identified risks related to PFAS.

The EU has decided to ban 200 PFAS substances in phases, starting February 2023. This is the first time the EU has imposed a ban on several chemicals of similar structure and properties all at once.

With respect to the USA, under the Biden-Harris Administration, the US Environmental Protection Agency has established a National Primary Drinking Water Standard for PFOA/PFOS and in February 2021, published a final determination to regulate PFOA and PFOS while also evaluating additional PFAS and determining what regulatory actions may be required to address groups of PFAS.

Considerations for the Property Industry

Perhaps because the United States of America is a notoriously litigious region of the world, it is often a bellwether on environmental protection and contamination issues. Accordingly, and as awareness of the potential risks to human health and the environment from PFAS have emerged, the number of lawsuits being filed against national and multi-national corporations manufacturing PFAS has increased dramatically. Companies including 3M Co., Chemguard Inc., Kidde-Fenwal Inc., National FoamInc., and Dynax Corp. are being systematically sued in class action law suits for billions of dollars. For 3M alone a “worst-case scenario” assessment for the company has estimated total liabilities could reach $30 billion.

The majority of claims fall into the following five categories:

• Personal injury claims;
• Water provider claims from utilities that must pay for clean-up of PFAS in drinking water;
• Property diminution of value claims, especially by airports where the ground is now contaminated;
• Claims by state attorneys general with natural resource damage cases, especially with fishing or hunting;
• Medical monitoring cases.

Currently, the vast majority of lawsuits surrounding PFAS appear to be targeting the manufacturers. However, establishing an understanding of whether a particular site has the potential to have been impacted by PFAS will provide any stakeholders with information on factors that could influence the value of land, whether it may the subject of regulatory intervention, with the possibility of subsequent remediation costs or delays to (re)development, all of which open up the potential of reputational risk.  

Therefore, during property transactions and development, Environmental Assessments are key to ensuring potential risks and liabilities are identified at an early stage, allowing informed decision making to be undertaken to enable the commercial success and also protect people and the environment from harm.

Where a Desk Based Assessment is commissioned for any particular site, a conceptual site model can be developed assessing current and historic site users, and whether PFAS may have been used on and near to a particular site. The assessment would also evaluate potential preferential pathways and the sensitivity of the receptors, which may include humans or Controlled Waters, for example. A desk based assessment may identify a number of the factors similar to those illustrated in the table below.

Many PFAS have the potential to migrate from their point of release, forming plumes within permeable soils and groundwater. Or, given their persistence, they can remain in-situ in the ground indefinitely. Therefore, the development of a Conceptual Site Model (CSM) to define risks posed by specific PFAS to potential receptors provides a very useful tool for evaluating the overall risk to a site which could by association potentially affect land value.

Conclusions

As the risks to sensitive receptors from PFAS becomes more apparent, tighter regulation is sure to follow. Therefore, the value of carrying out an informed assessment to determine whether sites are at risk from PFAS will serve to allow future liabilities to be determined and pragmatic risk management strategies to be developed, thereby supporting the decision-making process

Roberts Environmental Limited (REL) can evaluate the environmental risks and liabilities associated with the transaction and development of properties in relation to PFAS, as well as a wide range of other chemical contaminants and geological hazards, such as coal mine workings, allowing informed decisions to be made. At REL, we pride ourselves on safeguarding people's health and the environment, providing pragmatic professional advice enabling sustainable development and investment to create shared value, and improve local economies and communities.

Our Consultants at Roberts Environmental can provide informed, technical advice when considering emerging chemical risks such as PFAS. We help our clients to anticipate, avoid and mitigate significant future impacts and protect them from unexpected costs, liabilities and delays.