Forever chemicals, forever risks: PFAS greenwashing in the UK

Greenwashing Risk | 25/02/2026

PFAS (or more formally "per- and polyfluoroalkyl substances") are harmful chemicals that remain in the environment indefinitely. They are also known as "forever chemicals" and have been linked to serious health conditions such as cancers, thyroid disease and fertility issues. PFAS are present in a wide range of consumer and industrial products, including non-stick frying pans, ski wax, and firefighting foam.

There are concerns that PFAS could pose litigation risks akin to asbestos, another widespread industrial product once thought safe. By November 2023 PFAS payouts had reached $16.7 billion; there are predictions that they could hit $70 billion in coming years.¹

For example, between 2018 and 2025, the US chemicals manufacturer 3M paid out $11.5 billion for PFAS claims. BASF faces more than 4,500 PFAS lawsuits over allegedly harmful firefighting foam. The German chemicals major plans to remove PFAS from most of its products, citing the EU's widening rules. In Italy, a court recently convicted eleven executives from Miteni, a former subsidiary of Mitsubishi, for contaminating drinking water with PFAS. They were sentenced to a total of 141 years in prison.

Growing PFAS greenwashing litigation

Most PFAS lawsuits to date have been mass tort claims based on environmental harms but increasingly, claims are being brought in relation to greenwashing. For those unfamiliar with the terminology, “greenwashing” refers to false or incorrect claims relating to environmental sustainability made by companies to encourage sales.

In the US, there are already a number of instances of greenwashing litigation. W. L. Gore & Associates, the maker of Gore-Tex, has been accused of misleading customers by labelling its products as environmentally-safe or PFAS-free. A class action in North Carolina, filed in January 2025, claims that Apple inaccurately labelled its watches as safe, environmentally sustainable, and promoting human health, despite knowing they contained PFAS. Two makers of leakproof underwear, Thinx and Knix Wear, settled class actions in the US for $5 million and $1.4 million, respectively, which alleged they had misleadingly claimed their products were free of forever chemicals.

No PFAS claims appear to have been filed yet in the UK. This may change in 2026, given the snowballing of cases in other jurisdictions. A recent report found that 37% of Londoners "would be willing to support legal action against a company using PFAS".² One potential case looms large: a campaign group in Bentham, North Yorkshire, has instructed lawyers to investigate a potential mass tort claim. The town is considered to have the highest levels of PFAS in the UK, allegedly caused by a local manufacturer of firefighting foams.

UK regulations on PFAS greenwashing

In the UK, the manufacture and sale of PFAS are largely governed by UK REACH, a watered-down version of the EU's Restriction, Evaluation, Authorization and Restriction of Chemicals regulation. The Health and Safety Executive (the "HSE") oversees UK REACH.

Other enforcement bodies deal with greenwashing in the UK. The Competition and Markets Authority (the "CMA") can fine companies up to 10% of their global revenues, under the Digital Markets, Competition and Consumers Act 2024. The CMA's Green Claims Code applies a principles approach, based on statute:

1. "claims must be truthful and accurate;
2. claims must be clear and unambiguous;
3. claims must not omit or hide important relevant information;
4. comparisons must be fair and meaningful;
5. claims must consider the full life cycle of the product or service; and
6. claims must be substantiated." ³

The Financial Conduct Authority (the "FCA") and Advertising Standards Authority (the "ASA") also highlight greenwashing as an area of concern. The FCA's rule ESG 4.3.1R for authorised firms requires sustainability labels be:

1. "consistent with the sustainability characteristics of the product or service"; and
2. "fair, clear and not misleading". ⁴

Likewise, the ASA's UK Code of Non-broadcast Advertising and Direct & Promotional Marketing (known as the "CAP Code") says, "marketers should take account of the [CMA's] Green Claims Code…". ⁵ Criminal offences may also apply to the most egregious greenwashing, particularly the new corporate offence of a "failure to prevent fraud".

Despite these existing powers, regulators have taken only limited action on PFAS. In its role as the agency leading enforcement of UK REACH, the HSE ran a consultation on PFAS in firefighting foams, which closed for submissions on 18 February 2026. This narrow scope contrasts with the expansive regulatory discussions underway in the EU, which is weighing a ban on all but essential PFAS. The UK is slowly catching up. On 3 February 2026, the government published its first "PFAS Plan", aiming to accelerate the restriction of PFAS sources under UK REACH and align more closely with trading partners such as the EU, by December 2028. ⁶

Growing political interest is pressuring UK regulators to take a tougher stance and use the tools already at their disposal. In April 2025, the House of Commons' Environmental Audit Committee launched an inquiry into PFAS, with the Chair saying, "News coverage has exposed the level of problems with PFAS, and has shone a light that the UK’s regulatory approach is far less active than in many other jurisdictions." ⁷

How should companies prepare?

Greenwashing litigation comes in many forms, as outlined in Stephenson Harwood's "Identifying your Greenwashing Litigation Risk" series. As the UK's regulatory and political landscape starts to shift, and claims expand in the US and EU, UK companies and directors could face growing allegations of PFAS greenwashing from shareholders, consumers, and clients. Companies, insurers and professional advisors in the UK are waking up to these commercial and legal risks. The Lloyds Market Association convened a forum on insuring PFAS litigation risks, in late October 2025, and the Royal Society of Chemistry hosted a "Toxic Tort" conference on PFAS class actions, last November.

As well as engaging with expert bodies, companies should review their product and service descriptions and check for PFAS in their supply chains. Retailers may wish to secure indemnities from manufacturers, especially after the CMA's new guidance on "Making Green Claims" says it will hold retailers liable for greenwashing on branded products.⁸Beyond auditing and removing forever chemicals from supply chains wherever possible, companies should ensure they have evidence to support claims that products are PFAS-free, safe for people and/or animals, and environmentally sustainable. They should also consider the risk of PFAS pollution throughout the full life-cycle of a product or service. Companies may wish to consider litigation insurance and engaging legal advisors to minimise their exposure to lawsuits.

What can Stephenson Harwood do for you?

Stephenson Harwood's greenwashing team can help mitigate risks to your business. We can provide training and advice on greenwashing litigation, including in relation to PFAS, and on related claims from regulators, class actions, business customers, and shareholders.

With thanks to Joseph Hearn for their contributions to this article.