What are forever chemicals, and why does the EU want to ban them?

“Forever” usually has positive connotations. But sometimes we don’t want things to last forever – pollutants, for example.

Risk experts surveyed for the World Economic Forum’s Global Risks Report 2024 said pollution was one of their top 10 concerns, both now and over the next decade.

“Forever chemicals” are a case in point. These hardy substances – also known as per- and polyfluoroalkyl substances (PFAS) – do not break down.

They build up in the environment and the human body over time and have been linked to various health problems. There is a growing amount of regulation banning or restricting their use, including from the European Union (EU) and several US states. The OECD is also calling on its members to restrict or ban the substances.

However, the properties of PFAS are also considered vital to many net-zero technologies such as electric car batteries and fuel cells, as well as in healthcare.

Here’s what you need to know about PFAS.

PFAS are synthetic chemicals widely used in consumer products since the 1950s. Today, there are almost 15,000 chemicals in this group, the US National Institute of Environmental Health Sciences (NIEHS) reports.

Properties such as water repellence and stain resistance made them ideal choices for anything from food packaging, non-stick cookware, clothes and carpets to fire-extinguishing foam. At the root of their near indestructibility are strong carbon-fluorine bonds, which are hard to break.

As PFAS break down slowly, if at all, they accumulate in the environment, and the human body. In a 2012 study reported by the NIEHS, 97% of Americans were found to have PFAS in their blood.

PFAS can be found in many places where humans are exposed to them, the US Environmental Protection Agency (EPA) says. These include drinking water contaminated with PFAS, foods such as fish or meat exposed to PFAS in the environment, using products made with PFAS or breathing air containing the substances.

The EPA points to a growing body of research about the potential health impacts of PFAS. Exposure to the chemicals may lead to decreased fertility, developmental delays in children and raise the risk of certain cancers. The body’s immune and vaccine response and hormones may also be affected.

However, pinning these effects down is not straightforward due to the large number of PFAS and their wide range of uses.

Restricting the use of PFAS for this reason has to be balanced with the fact that the chemicals play a critical role in the development of clean tech needed for the net-zero transition.

Fluorogases (F-gases) for example – a type of PFAS – are key elements in electric car batteries and heat pumps, which are both important technologies for decarbonizing transport and home heating, Energy Monitor explains. PFAS are also used in wind turbines. Another type, fluoropolymers, is key to the production of carbon-free hydrogen through electrolysis, an important technology for achieving net-zero emissions over the next two decades.

While alternatives are available, these may not provide the same results. Energy Monitor quotes a heat pump manufacturer who said using these would reduce the emissions savings that can be achieved.

US manufacturer Chemours – the company behind Teflon – also points to the role PFAS play in lithium-ion batteries for electric cars, providing higher energy density and longer driving ranges.

Following an initiative by member countries, the EU is planning to restrict the use of PFAS through its REACH regulation for chemicals. The ban would extend to around 10,000 different substances, banning them in their entirety. The plans are currently being reviewed by ECHA, the European Chemicals Agency, which is expected to publish its findings at its next plenary meeting in March 2024.

If the ban is imposed, companies would have between 18 months and 12 years to find alternatives, though there would be some “derogations” or exceptions.

The EU has also set thresholds for PFAS in its water quality directive, which will take effect in 2026, while ECHA has proposed restrictions on fire-fighting foams containing PFAS.

Beyond a growing number of state-level bans, the US Environmental Protection Agency has been building a national portfolio of regulations to phase out the use of PFAS and safeguard communities from contamination.

Internationally, similar initiatives have either been implemented or are underway.

However, an academic paper investigating the EU’s plans has warned that, while trying to protect human and planetary health, a blanket ban could raise new issues. Alternative materials could end up being less safe, slow the net-zero transition or reduce the effectiveness of healthcare, the authors say.

Legislators need to carefully weigh up these challenges when considering a more targeted approach. Alongside, scientific efforts to develop and scale ways of recovering or filtering out PFAS before they can harm the environment and humans may help address the risks posed by these forever chemicals.