DEFRA has made The Control of Mercury (Enforcement) (Amendment) Regulations 2025 (SI 2025/1189), updating the UK’s enforcement regime for mercury in Northern Ireland under the Windsor Framework. Made on 12 November 2025 and in force from 3 December 2025, the instrument aligns domestic enforcement with Regulation (EU) 2024/1849 and the European Commission’s 19 July 2024 Notice setting specific arrangements for Northern Ireland.
Parliament approved the regulations by affirmative resolution, as required by paragraph 8F(1) of Schedule 7 to the European Union (Withdrawal) Act 2018. The Secretary of State relied on powers in section 8C(1) and paragraph 21 of Schedule 7 to that Act and had special regard to section 46 of the UK Internal Market Act 2020. The draft was laid on 17 July 2025.
Customs powers are widened. Regulation 33 of the 2017 Regulations is amended so HMRC and Border Force may assist with enforcing Article 10(7) of the EU Mercury Regulation: the export ban on dental amalgam in Northern Ireland and-after 31 December 2034-the import ban. This provides a statutory basis to seize and detain suspect consignments alongside existing controls on mercury and mercury‑added products.
Schedule 1 to the 2017 Regulations is updated so the measures introduced by Regulation (EU) 2024/1849 are listed as ‘relevant provisions’ for UK enforcement. For Northern Ireland, the listing is modified so that, until 31 December 2034, the Union‑wide clinical‑use ban in Article 10(2a) and the import ban in Article 10(7) second subparagraph do not apply where a registered dentist or registered dental care professional treats a UK‑resident patient in Northern Ireland.
Regulation (EU) 2024/1849 phases out dental amalgam in the Union by prohibiting use from 1 January 2025 unless strictly necessary, banning exports from 1 January 2025, and banning import and manufacture from 1 July 2026. The Commission Notice confirms these provisions apply in Northern Ireland under the Windsor Framework.
A time‑limited derogation is set out for Northern Ireland. Use and import of dental amalgam for the treatment of patients residing in the United Kingdom may continue until 31 December 2034, or until an earlier phase‑out date is agreed under the Minamata Convention. The Commission will monitor compliance and may maintain or withdraw the Notice based on that evidence.
Conditions attach to the derogation. Only UK‑resident patients may receive amalgam; treatment must be by a practitioner registered in Northern Ireland; imports must be commensurate with clinical need; and annual data on imports and usage must be reported by 31 December each year. From 1 July 2026, imports must meet customs formalities for ‘specific medical needs’, and movements from Great Britain to Northern Ireland are treated as ‘category 1 goods’ under Joint Committee Decision No 1/2023.
Manufacture of dental amalgam in Northern Ireland is prohibited from 1 July 2026. Export of dental amalgam from Northern Ireland to destinations outside the United Kingdom is prohibited from 1 January 2025. These prohibitions operate alongside the domestic use and import derogation through to 2034.
The instrument defines who may rely on the derogation by reference to the Dentists Act 1984: ‘registered dentist’ and ‘registered dental care professional’ both take their meanings from section 53(1). This confines use during the derogation to registrants within the dental regulator’s framework.
The amendments operate only with respect to Northern Ireland. The 2017 Regulations remain the baseline UK regime, including customs assistance and offences, with the EU Mercury Regulation read ambulatory for Northern Ireland under the Windsor Framework. DEFRA’s note indicates no, or no significant, impact on the private, voluntary or public sector, with a de minimis assessment available.