In situ generated active substances can be defined as substances, which are generated at the place of use from one or more precursors.
For in situ generated active substances, the biocidal product which is subject to authorisation before it can be supplied or used is either:
- the substance(s) or mixture(s) generating the active substance; or
- the active substance generated from substances or mixtures, which cannot themselves be authorised as biocidal products.
For all substances generated in situ, the active substance shall be defined by reference to the precursor(s) supported in the dossier under evaluation and to the substance generated.
This may in certain cases lead to a re-definition of the substance, as originally notified, and/or to the creation of additional entries, when data on several precursors were provided in a dossier, or when multiple dossiers have been submitted for a substance (e.g. chlorine dioxide to be redefined as Chlorine dioxide generated from sodium chlorite by electrolysis and as chlorine dioxide generated from sodium chlorate and hydrogen peroxide in the presence of a strong acid).
At the time of the substance approval, the Commission implementing Regulation would then refer to the precursor(s) supported in the dossier and to the active substance that will be generated from this(ese) precursor(s), including when relevant the generation method.
In the case of in situ generated active substances, the dossier or LoA will need to cover data on both the in situ generated active substance and the precursor(s), which form the representative product, supported in the dossier under evaluation.