US EPA released its workplan for the evaluation of L-glufosinate, among others

Date:07-11-2023

L-glufosinate (L-configuration) is the active ingredient with the main herbicidal activity in the racemic mixture of glufosinate (containing both L- and D-configurations). As a novel chiral herbicide, the registration and application of L-glufosinate are of significant importance in reducing the environmental presence of the ineffective ingredient (D-glufosinate). This contributes to improving pesticide utilization and alleviating environmental pressure.

Registration of L-glufosinate in the U.S.

L-glufosinate has already been registered and marketed in China and Japan, and now, its registration in the U.S. has entered the final crucial stage.

Currently, two varieties of L-glufosinate are being advanced for registration in the U.S. market. The registration of L-glufosinate ammonium TC was initially pursued by Agrimetis and successfully advanced by BASF after its acquisition of the former. Agremetis/BASF did not submit complete registration data. Instead, they utilized BASF’s existing registration data for racemic glufosinate for data bridging, supplementing only the key differentiating data. This approach significantly improves the overall registration efficiency of L-glufosinate.

Following BASF, United Phosphorus Limited (UPL) has also initiated the registration of L-glufosinate ammonium in the U.S. UPL’s registration strategy is similar to BASF’s. It has completed the minimum data package required for registration and has entered the subsequent review stage.

The application of L-glufosinate free acid TC was initially held by Meiji Seika Pharma and then acquired by Mitsui Chemicals. In terms of registration data, Meiji Seika Pharma/Mitsui Chemicals made use of the advantages brought by the OECD GLP data mutual recognition system. They directly utilized the complete data obtained from registration of L-glufosinate free acid in Japan to fulfill the requirements for its registration in the U.S. This facilitates the progress of the chemical’s registration in the U.S.

Latest US EPA workplan released

According to the latest workplan of the U.S. Environmental Protection Agency (US EPA), the evaluation on BASF’s L-glufosinate ammonium and Mitsui Chemicals’ L-glufosinate free acid is scheduled to be completed by the end of 2023. Due to the slightly late submission of dossier, the evaluation on UPL’s L-glufosinate ammonium is scheduled to be completed in July 2024.

According to the workplan, since L-glufosinate is essentially the purification of the active ingredient with the main herbicidal activity in the racemic glufosinate, in principle, the existing residue level requirement on racemic glufosinate can be adopted. This approach significantly reduces the data requirements for L-glufosinate’s registration. However, the final conclusion regarding residue level requirement on L-glufosinate is still pending the official release of the subsequent EPA evaluation.

The latest workplan for other new chemical pesticide varieties also revealed

In addition to L-glufosinate, the latest US EPA workplan also includes the evaluation progress of other new chemical pesticide varieties. These evaluations encompass both the registration of novel active ingredients and the applications for new uses of already registered varieties. The pesticide varieties involved are listed below:

However, it should be noted that the release of this latest workplan does not necessarily mean that the US EPA will be able to complete the evaluations according to the proposed timeline. Due to workload constraint and personnel shortage, there is still a high possibility of delay in the evaluation of these pesticides.

US EPA’s latest workplan (Source: US EPA)