Commission Implementing Decision (EU) 2026/2132 of 24 September 2026 allowing France to authorise biocidal products containing ethylene oxide for the protection of cultural heritage (notified under document C(2026) 6660)

Ethylene oxide in product-type 2 (disinfectants and algaecides not intended for direct application to humans or animals), as defined in Annex V to Regulation (EU) No 528/2012, was included in the work programme for the systematic examination of all existing active substances contained in biocidal products referred to in that Regulation, as set out in Annex II to Commission Delegated Regulation (EU) No 1062/2014 (2). An application for approval of ethylene oxide in product-type 2 was submitted on 1 December 2009.

Commission Implementing Decision (EU) 2025/1074 (3) found that the representative product included in the application for approval was not within the scope of Regulation (EU) No 528/2012 and that, as a consequence, it was appropriate to not approve ethylene oxide as an active substance for use in biocidal products of product-type 2.

In accordance with Article 55(3) of Regulation (EU) No 528/2012, on 21 November 2025, France submitted to the Commission an application for a derogation from Article 19(1), point (a), of that Regulation, in which it asked to be allowed to authorise biocidal products containing ethylene oxide for the protection of cultural heritage, specifically for the protection of archive material.

In its application, France explained that cultural heritage objects, and more specifically archives are particularly exposed to biological and environmental risks. Among these, mould represents a concrete threat capable of irreparably degrading supports such as paper or other organic material. Damage can occur in a short time and lead to irreversible archive losses of inestimable value. Despite the implementation of preventive techniques (temperature and humidity control of storage, regular cleaning, hygiene of the premises), certain situations, in particular after water damage, may lead to massive growth of mould.

According to the information provided by France, ethylene oxide is currently the most effective and suitable solution for the treatment of archive material. There are no appropriate alternative methods for the treatment of such material. According to France, dusting and buffing with ethanol (dusting using filter vacuum cleaners and brushes to remove free particles and surface spores followed by a localised application of pure or diluted ethanol) is effective for surface contamination but not for internal contamination, may alter certain inks and pigments, requires long and delicate treatment and is therefore not suitable for the treatment of large volume fungal infestation. Gamma radiation is a very costly and difficult to replicate technique which requires specific equipment, available in France only on one site, where the material to be treated would need to be transported. In addition, according to France, gamma radiation has been shown to be incompatible with certain material, in particular transparent and translucent material and to cause relevant degradation of cellulose, significantly reducing the stability and durability of documents. Low temperature techniques can stop the growth of mould but are not effective against spores.

As indicated by France in the application, products containing ethylene oxide are used by fumigation by trained professionals. Considering its hazard properties (very toxic by ingestion and inhalation, corrosive to skin and eyes and liable to cause irritation of the respiratory tract and having mutagenic, carcinogenic and reprotoxic effects in the long term), its use follows a very strict and controlled process comprising: thorough prior assessment of the infestations, identifying the biological nature of the contamination and determining the compatibility of the materials with the treatment; establishment of an airtight enclosure; controlled gas diffusion, according to standardised parameters (homogeneous and effective concentration while limiting the risk of degradation of fragile supports such as paper, leather, textile); strictly confined exposure phase, carried out in the hermetic enclosure without human presence; prolonged final aeration and desorption after treatment, ensuring complete removal of gaseous residues and restoration of a healthy environment before handling. The air charged with ethylene oxide is evacuated to a treatment system where the gas is destroyed or neutralised. According to France, this process ensures an effective treatment, while drastically limiting the risks for the trained professionals using the products and for the treated objects.

The information and justification contained in the application submitted by France shows that the use of ethylene oxide is essential for the protection of cultural heritage artefacts and that there are no appropriate alternatives currently available for the treatment of archive material in France. The alternative techniques currently available are either not sufficiently effective or can cause damage to the materials treated.

Based on the information and justification provided by France, it is appropriate to conclude that ethylene oxide is essential for the protection of cultural heritage and that no appropriate alternatives are available in France. France should therefore be allowed to authorise biocidal products containing ethylene oxide for the protection of cultural heritage, specifically for the protection of archive material,