HSE Confirms Dimethomorph Withdrawal And GB Stock Deadlines

The Health and Safety Executive has confirmed that approval of dimethomorph for use in plant protection products in Great Britain will end on 30 November 2026. Its 2 November announcement sets separate deadlines for removing existing products from the supply chain.

Dimethomorph is a fungicide active substance. The decision concerns its approval for plant protection products in Great Britain. Producers and users have different periods for selling products and managing existing stocks.

Approval And Stock Deadlines

HSE's final decision gives three dates:

• 30 November 2026: active-substance approval ends.
• 31 May 2027: sale and distribution of products must end.
• 31 May 2028: disposal, storage and use of existing stocks must end.

The November announcement describes six months for producers to sell and distribute products, followed by a further 12 months for users to manage existing stocks. Those periods form a phased withdrawal programme.

Reasons For Withdrawal

HSE concluded that dimethomorph no longer meets the approval criteria under assimilated Regulation 1107/2009. The decision cites endocrine-disrupting properties in humans and classification as toxic to reproduction, category 1B, for effects on fertility.

The decision says products containing dimethomorph can no longer be authorised in Great Britain and existing authorisations must be withdrawn under that regulation.

From Proposal To Final Decision

HSE announced its proposed withdrawal on 31 July 2026, following a review of new scientific information. Consultation with trading partners through the World Trade Organization followed.

The final decision is dated 16 October. It records that consultation comments did not materially alter HSE's decision and that producers were notified on 20 October. The public bulletin confirming expiry and stock deadlines was issued on 2 November.