ANSES largely bans S-metolachlor, a very common agricultural weedkiller

A decision against the advice of the Minister of Agriculture. The main uses of S-metolachlor, a powerful herbicide, will be banned in France, according to decisions published Thursday, April 20 by the Health Security Agency (Anses). Derivatives of this pesticide have been detected above authorized limits in groundwater, according to the agency.

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This herbicide is mainly used for the cultivation of corn as well as for sunflower, soy or beet. It has been authorized since 2004, almost twenty years ago. The sale and distribution of plant protection products based on S-metolachlor will remain authorized until October 20, 2023 and stocks of these products, widely used on corn, sunflower and soybean, can be used until October 20, 2024 .

Groundwater pollution

ANSES announced in February that it wanted to ban the main uses of S-metolachlor: after use in the fields, this substance degrades into chemical derivatives, “metabolites”, which are found in soils, surface waters and waters. underground – and therefore potentially in drinking water. At the time of “controls of water intended for human consumption”, derivatives of this pesticide have been “frequently detected at concentrations exceeding quality standards”, the agency said.

The fate of this herbicide had aroused emotion in the agricultural world, the majority union FNSEA demanding its maintenance “lack of alternatives”. But the agency did not grant their request.