Changes of the chemical composition of authorised plant protection products

Date: 3 June 2020

Plant protection products are mixtures of one or more active substances and so called co-formulants. The chemical composition of a plant protection product determines not only its physico-chemical properties but also the environmental behaviour as well as toxicological and eco-toxicological properties. Consequently a change in composition may influence and alter these properties. Therefore, the process of a composition change is strictly regulated (SANCO/12638/2011, 20 November 2012 rev. 2). A revision of this guideline is available as draft (rev. 3, 29.11.2019), which is more detailed that the previous one.

This draft guideline specifies three types of changes (one is a two tiered approach) versus two categories in the recent guideline. Type 1 and Type 2 (Tier 1) of the new guideline are non-significant changes in the recent guideline, while Type 2 (Tier 2) and Type 3 are significant changes.

Type 1 changes are administrational changes (e.g. Typos or error correction, improvement in a.s. purity, etc).
Adding equivalent co-formulants or replacing co-formulants by equivalent ones are Type 2 changes. The evaluation of this type of change is a two-step process. The CAS numbers of the co-formulants and the classification and labelling should be identical (Tier 1). If this is not the case, a Tier 2 assessment based on the comparison of specific physical-chemical or technical properties of the old and new PPP are needed. This might require physical-chemical studies.
Type 3 changes are changes, where co-formulants are exchanged, added, omitted or whose content is changed. Depending on the extent of the changes, new studies on toxicological and eco-toxicological properties might be required.

In the case of Type 1 changes a notification to the authorities is sufficient, while in the case of Type 2 (Tier 1 and Tier 2) or Type 3 an application for an amendment of the authorisation is required. Type 1 changes should be approved by authorities within three months, whereas the two other types will take six months for the assessment.

Thomas Reisinger