On May 3, 2022, the Court of Appeal for Administrative Litigation in Economic Matters ("College van Beroep voor Het Bedrijfsleven") decided to refer three questions to the Court of Justice of the European Union for a preliminary ruling in the context of a litigation concerning the renewal of marketing authorizations for three plant protection products based on fludioxonil (Pitcher), difenoconazole and fluxapyroxad (Dagonis), and sulfoxaflor (Closer). They relate to the division of competences of the authorities involved in the authorisation of plant protection products, under Regulation No 1107/2009, in particular, in relation to the questions whether and how the most recent scientific and technical knowledge should be taken into consideration in that authorisation process.

Indeed, PAN Europe accuses the Dutch Committee for the Authorization of Plant Protection Products and Biocides (College voor de toelating van gewasbeschermingsmiddelen en biociden or "CTGB"), in charge of the pesticide approval process, of adopting deliberately outdated and unsuitable assessment methods, whereas the use of more up-to-date methods shows that several of the authorized products are in fact above European thresholds for the acceptability of risks to health and the environment.

More specifically, with regard to fludioxonil and difenoconazole, PAN Europe complains that the CTGB failed to take into account recent scientific studies demonstrating the endocrine-disrupting nature of these two substances during the registration renewal process. PAN Europe argues that European regulations, insofar as they require member states to take into account "the current state of scientific and technical knowledge", and in particular the possible "endocrine disrupting effects that may be harmful to humans", mean that the national approval process must be updated in line with new scientific discoveries. In concrete terms, this implies that even when a substance has been authorized, a new discovery of potentially harmful effects on human health or the environment must result in an updated review of the substance's toxicity and, ultimately, of its registration. In the case of sulfoxaflor, PAN Europe considers that the CTGB did not use the most recent documentation on the product's harmful effects on bees.

In her opinion dated September 28, 2023, the Advocate General at the CJEU, Leila Medina, ruled in favor of the applicant association. She adopted the following positions:

On the one hand, she recalls that a member state may if it considers, in the light of "developments in scientific and technical knowledge", that a pesticide, with an active substance authorized by the European Union (EU), is harmful to human health or the environment, refuse to register a product containing this substance, or modify or withdraw a previously granted registration. In doing so, member states are not limited to the guidance documents provided by the EU, and may refer to any current and relevant scientific source.

Thus, in assessing an application for registration of a plant protection product, "a Member State must take account of all current (i.e. most recent), relevant and reliable scientific and technical knowledge, irrespective of the source or document from which it is derived". This implies that a Member State may deviate from the assessment carried out by the EU or by the rapporteur Member State of the zone to decide, on the basis of relevant documentation, that a product is sufficiently harmful not to be registered.

On the other hand, relying on the Blaise ruling handed down by the CJEU (C-616/17), according to which "it is incumbent on the competent authorities, in particular, to take account of the most reliable scientific data available and the most recent results of international research", the Advocate General holds that a plant protection product can only be approved if, according to the current state of scientific and technical knowledge, it has no harmful effect on health and the environment.
This means that the scientific knowledge taken into account in assessing the effects of the substance must be the most recent available. This interpretation is in line with the precautionary principle enshrined at European level.

The Advocate General also argues that the registration of a product by national authorities is not a direct continuation of the Commission's authorization of the active substance, so that the Commission's authorization does not automatically translate into the registration of all products containing the active substance at national level.

While the CJEU is not bound by the Advocate General's conclusions, they nonetheless point to an encouraging trend for the forthcoming decision.