Residues of active substances affect the purification process during the preparation of drinking water. A guidance document is now available to assess these effects. From April 2026, the Ctgb will use this guidance as part of the relevant assessment.

Both the Biocidal Products Regulation and the Plant Protection Products Regulation mandate assessment of the impact of water treatment processes on residues of active substances and any metabolites in water abstracted for the production of drinking water. The European Commission previously requested EFSA and ECHA to develop guidance on how this impact should be assessed. Although the guidance in question was published in 2023 (EFSA Journal 2023;21(8):8194), the SCoPAFF Phytopharmaceuticals-Legislation and the CA have recently decided how this guidance applies to biocidal products and plant protection products , respectively:

  • Biocidal products (CA meeting, 24 June 2024, Doc 7.2) 
    The guidance is in force for new applications for substances and products submitted from 1 April 2026, but not for substances in the review programme. It is therefore also in force for applications for biocidal products containing active substances that have not yet been assessed in accordance with this guidance. Assessment in accordance with the guidance will then take place within the product dossier.
  • Plant protection products (PAFF-PPL-March 2024-Doc.A.07.03 rev. 1, 20 March 2024)
    In accordance with Article 7 of Regulation (EC) 1107/2009 and Article 5 of Regulation (EU) 2020/1740, the guidance is in force for all applications for substances that are submitted from 1 April 2026. It is also in force for all applications for plant protection products containing active substances that have already undergone such an assessment. However, it is not in force for applications for plant protection products containing active substances that have not yet been assessed in accordance with this guidance.

From 1 April 2026, the Ctgb will start assessing applications for plant protection products and biocidal products according to these European agreements. National interpretation, if any, will be added to the Evaluation Manuals (EM) at a later date once more information on this aspect is available.