UK REACH authorisation refusal highlights the importance of evidence on alternatives

A recent UK REACH authorisation decision provides an important illustration of how evidence on alternatives can determine the outcome of an application, even where the socio-economic benefits of continued use are found to outweigh the risks.

On 25 August 2026, the Secretary of State for Environment, Food and Rural Affairs refused an application from Vertik-Al Limited for a consortium of seven companies for continued use of chromium trioxide in the pre-treatment conversion coating of aluminium for the construction industry.

The decision is particularly relevant for companies preparing UK REACH Applications for Authorisation (AfAs) or future review reports because it demonstrates the importance of the relationship between the Analysis of Alternatives (AoA), substitution planning and Socio-Economic Analysis (SEA).

In this case, the socio-economic benefits of continued use were found to outweigh the risks to human health. Authorisation was nevertheless refused because it had not been demonstrated that there were no suitable alternative substances or technologies.

What happened?

The application concerned the use of chromium trioxide for pre-treatment conversion coating of aluminium by spray and dip processes across seven companies.

Chromium trioxide is included in Annex XIV of UK REACH because of its carcinogenic and mutagenic properties. As no derived no-effect level can be established for these properties, authorisation could not be granted on the basis of adequate control under Article 60(2). The application was therefore considered under the socio-economic route in Article 60(4).

Under this route, two relevant conditions need to be satisfied: the socio-economic benefits must outweigh the risks to human health or the environment, and there must be no suitable alternative substances or technologies.

The UK Agency for REACH evaluated the application and, in its Opinion of 6 November 2025, concluded that the conditions in Article 60(4) had been met. It recommended granting an authorisation with a four-year review period, substantially shorter than the 12 years requested by the applicants.

However, the final decision reached a different conclusion on alternatives. While accepting that the socio-economic benefits outweighed the risks, the Secretary of State concluded that it had not been demonstrated that there were no suitable alternatives. Authorisation was therefore refused.

Socio-economic benefits and the Analysis of Alternatives are separate considerations

The decision provides a clear illustration of the separate roles played by the AoA and SEA within an application under the socio-economic route.

The Agency estimated monetised socio-economic benefits of at least £20.3 million over 12 years under a scenario in which the applied-for use ceased, or £3.5 million where applicants transitioned to a chrome-free alternative. This compared with monetised human health risks of up to £101,000 over the same period.

The final decision agreed that the socio-economic benefits outweighed the risks.

That was not sufficient to secure authorisation.

The separate requirement concerning suitable alternatives also had to be satisfied. The decision concluded that the applicants had not provided sufficient evidence to demonstrate that alternatives which were generally available were unsuitable for them.

For companies preparing applications or review reports, this reinforces the importance of treating the AoA as a central part of the authorisation case. Evidence that socio-economic benefits outweigh the risks does not remove the separate requirement to demonstrate that there are no suitable alternatives.

What does the decision indicate about evidence on alternatives?

Several aspects of the decision are particularly relevant to future applications.

The circumstances of individual applicants matter. The consortium members were at different stages of substitution. Some had already invested in alternative processes, while others faced technical, logistical or economic barriers. The decision illustrates the importance of demonstrating technical and economic feasibility in the circumstances of the individual applicants.

Technical difficulties may not, by themselves, demonstrate that an alternative is unsuitable. Wet adhesion failure was an important technical issue for some applicants. However, evidence presented through the consultation indicated that other companies had encountered similar difficulties and subsequently overcome them. In this case, this contributed to the conclusion that the applicants had not sufficiently demonstrated that substitution was infeasible.

Evidence from comparable companies can be significant. Stakeholders responding to the consultation reported that approximately 80% of the same sector were using alternatives. The final decision considered this evidence alongside the fact that some members of the applicant consortium were themselves operating chrome-free processes.

For future applicants, this suggests that where apparently comparable organisations have already substituted, robust evidence may be needed to explain why their experience is not directly transferable to the applicant’s own technical requirements, processes or economic circumstances.

Costs need to be linked to feasibility, rather than simply identified. The applicants provided information on the costs associated with substitution, but the evidence was not considered sufficient to demonstrate that these costs made substitution economically infeasible. Quantifying investment requirements is therefore only part of the assessment; the evidence also needs to support the conclusion being drawn from those costs.

Substitution plans need credible timescales and supporting evidence. The applicants requested a 12-year review period, while the Agency recommended a four-year period. The final decision also identified limited information on the timeframe for progressing substitution over the requested period. In this case, the evidence on alternatives, expected pathway towards substitution and proposed review period were therefore closely connected.

Practical considerations for future UK REACH applications

AFA066 should not be interpreted as establishing a general rule for how future applications will be decided. Authorisation decisions depend on the circumstances and evidence associated with the particular use and applicants.

It does, however, highlight several questions that companies may benefit from addressing early when developing an authorisation or renewal strategy:

• What functions must an alternative deliver, and what evidence demonstrates whether candidate alternatives can meet them?
• Where trials have failed, is there evidence identifying the causes and demonstrating why those barriers cannot currently be overcome?
• If competitors or comparable users have substituted successfully, what material differences explain why their experience is not directly transferable?
• Are estimates of substitution costs supported by evidence showing why those costs affect economic feasibility?
• What substitution activities have already been undertaken, what progress has resulted and what remains to be resolved?
• Does the proposed substitution plan provide a credible and evidence-based timetable, and is this consistent with the requested review period?

The wider lesson from this case is that the substitution narrative needs to be supported throughout the application. Evidence of significant economic consequences from non-authorisation remains important, but it addresses a different part of the Article 60(4) test from the assessment of alternatives.

For applicants, this makes the interaction between the AoA, substitution plan and SEA particularly important. The assumptions and evidence underpinning each should tell a consistent story about what alternatives are available, what prevents their adoption today, how those barriers are being addressed and the timeframe within which substitution could realistically occur.

How RPA can support UK REACH authorisation

RPA supports organisations with UK and EU REACH authorisation, including Analysis of Alternatives, Socio-Economic Analysis and regulatory strategy.

For organisations considering a new application or preparing for an authorisation review, the AFA066 decision provides a useful opportunity to examine whether the evidence supporting alternatives, substitution timescales and socio-economic impacts is sufficiently robust and internally consistent.