Methoxychlor, Declorano Plus and UV-328 Ban: What Companies Must Do in 2025

Key data

If your company manufactures, imports or uses any of these three substances in its processes or products, the regulation is already in force. Decisions SC-11/9, SC-11/10 and SC-11/11 of the Stockholm Convention, adopted on 12 May 2023 and incorporated into Spanish law, establish a prohibition regime with very specific exemptions. Failing to act is equivalent to breaching an already enforceable obligation.

What does this regulation establish?

The three decisions incorporate three new prohibited substances into Annex A of the Stockholm Convention. Each has a different regime:

A critical nuance for Spanish companies: the EU has notified non-acceptance regarding UV-328. This creates a complex regulatory situation: the prohibition exists at the international level, but the European position introduces uncertainty about the applicable framework. Companies operating under European regulation must verify with special attention what regime applies to this specific substance.

Regarding spare parts, the exemption is limited: it only covers items in which these substances were already originally used. It is not an open exemption for any new part that incorporates these substances.

Economic and operational impact

The impact is not just regulatory: it has direct consequences for supply chain, homologations and product continuity.

• Reformulation of formulations and products: Companies using these substances outside exempt categories must replace them. This involves reformulation costs, new validation tests and possible production delays.
• Supply chain audit: It is not enough to not use the substance directly. If a supplier incorporates it in a component that you integrate, responsibility can reach you. It is necessary to map the entire chain.
• Management of existing stocks: Products already manufactured with these substances that are not covered by exemption cannot continue to be marketed without legal verification.
• Complexity for UV-328: The EU's non-acceptance creates a dual regulatory layer. Spanish companies that export to other EU countries or purchase components from European suppliers must analyze which rule prevails in each operation.
• Medical and in vitro diagnostic sector: Although they have exemption without a fixed deadline, they are subject to review in 2041. It is advisable to start planning alternatives now to avoid facing an abrupt change.

Who does it affect?

• Chemical industry: Manufacturers or distributors of methoxychlor, Declorano Plus or UV-328 must cease production and commercialization unless exempt.
• Aerospace sector: Use permitted with exemption until 2044, but must be notified and documented.
• Defense: Temporary exemption until 2044. Requires verification that the specific use is within the scope of the exemption.
• Automotive: Vehicle and component manufacturers that incorporate these substances have exemption until 2044, including spare parts for items where they were already originally used.
• Industrial machinery: Temporary exemption until 2044 for specific notified uses.
• Medical devices and in vitro diagnostic: Exemption without a fixed deadline, subject to review in 2041. It is the sector with the greatest time margin, but not exempt from planning.
• Importers and distributors: Any company that imports products containing these substances must verify whether the end use is covered by an exemption.

Practical example

A manufacturer of automotive components that uses Declorano Plus as a flame retardant in technical plastic parts finds itself in the following situation:

• Its use is covered by the automotive sector exemption, which extends until 2044.
• However, it must verify that its specific use is within the notified categories and that its suppliers of the substance also operate under the same framework.
• If it also manufactures spare parts, the exemption only covers it if those parts correspond to items where Declorano Plus was already originally used, not for new designs that incorporate the substance for the first time.
• If the same manufacturer exports components to customers in other EU countries and uses UV-328, it must take into account that the EU has notified non-acceptance of this substance, which may generate additional restrictions at destination.

A manufacturer of cleaning products that used methoxychlor as an active ingredient has no available exemption: it must have ceased its use since 26 February 2025.

What should companies do now?

1. Identify if you use any of the three substances in your products, processes or supply chain: methoxychlor, Declorano Plus or UV-328. If the answer is yes, move to the next step immediately.
2. Verify if your use is covered by an exemption: check if your sector (aerospace, defense, automotive, industrial machinery, medical devices, in vitro diagnostic) is within the exempt categories and if the specific use has been correctly notified.
3. Audit your supply chain: request from your suppliers a declaration of compliance regarding the use of these substances in the components they supply to you.
4. Manage the UV-328 case with special attention: if you use this substance and operate under European regulation, consult with a specialized legal advisor about the impact of the non-acceptance notified by the EU.
5. Plan for substitution even if you have a temporary exemption: the exemptions for Declorano Plus and UV-328 expire in 2044 and the medical sector has a review in 2041. Starting now the process of searching for alternatives avoids urgent costs in the future.
6. Document and file all verifications performed: in case of inspection, documentary traceability is the main line of defense.

Official source

Consult complete regulation in official source

Notice: This article is for informational purposes only and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-14331