Biocides: EU active substances non-approval decisions and no longer supported
This ebulletin contains information on regulating biocides in Northern Ireland (NI)

 

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Issued: 25 August 2026

This ebulletin contains information on regulating biocides in Northern Ireland (NI).

New EU active substance non-approval decisions

Biocidal products must be phased off the NI market.

Following withdrawal of support under the EU Biocidal Products Regulation (EU BPR), a decision has been taken not to approve the following active substance/product type combinations. This will affect NI:

  • 1,2-benzisothiazol-3(2H)-one (BIT) (CAS 2634-33-5 EC 220-120-9) in product type 9
  • terbutryn (CAS 886-50-0 EC 212-950-5) in product type 9
  • tetrahydro-1,3,4,6-tetrakis(hydroxymethyl)imidazo[4,5-d]imidazole-2,5(1H,3H)-dione (TMAD) (CAS 5395-50-6 EC 226-408-0) in product type 12

Likewise, following evaluation under the EU BPR, a decision has been taken not to approve the following active substance/product type combinations.

  • poly(dimethyloctadecyl[3-(trihydroxysilyl)propyl]ammonium chloride) generated from dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (CAS 27668-52-6 EC 248-595-8) in product types 2, 7 and 9


Biocidal products containing these active substances in the relevant product types can no longer be:

  • supplied in NI after 23 July 2027; or
  • used in NI after 23 January 2028


You must manage your stocks of the affected products to ensure they are removed from the NI supply chain by 23 July 2027.

New treated articles containing these active substances in the relevant product types cannot enter the supply chain or be imported into NI after 19 January 2027. Treated articles that have entered NI supply chains before this date can continue to be supplied and used.

Find out more about treated articles.

Any affected NI product approvals under the Control of Pesticides Regulations (COPR) will be revoked in line with the above dates.

If you are aware of any disproportionate negative impacts that are likely to arise from the non-approval of the active substance/product type combinations listed, please contact us.


Active substance no longer supported in the EU

Non-approval decision to be taken for unsupported active substance in the EU.

Following an opportunity for any person, company or task force/consortium to support the active substance/product type combination listed in the EU Review Programme, no compliant notification was received. This affects NI:

  • peracetic acid generated from tetraacetylethylenediamine and hydrogen peroxide (CAS 79-21-0 EC N/A) in product type 2


This active substance/product type combination will now be subject to an EU non-approval decision.

Once a decision is taken, the active substance will no longer be able to be used in biocidal products of the relevant product type in NI. In addition articles treated with such products will no longer be able to be placed on the market in NI. HSE will provide separate updates on the decision and relevant phase-out periods.

If you are aware of any disproportionate negative impacts that are likely to arise from the non-approval of the active substance/product type combination listed, please contact us as soon as possible.

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