Mepiquat chloride renewed until 29 February 2040: N-methylpiperidine up to 3 g/kg dry matter or 2 g/L of the technical concentrate; EFSA — HPLC-MS/MS with an LOQ of 0.01 mg/kg, ion chromatography in air, ADI lowered from 0.2 to 0.065 mg/kg bw
Commission Implementing Regulation (EU) 2025/150, published on 30 January 2025, renews from 1 March 2025 to 29 February 2040 the approval of the plant growth regulator mepiquat chloride and lifts the restriction to that single role. The Commission dropped the former condition of particular attention to residues in food, because the provisional assessment showed an acceptable risk even for critical consumer groups. It is based on the EFSA conclusion of 4 July 2024 (cereals and grass, formulation with ethephon); mepiquat chloride is not an endocrine disruptor.
- Annex: mepiquat chloride, 1,1-dimethylpiperidinium chloride, CAS No 24307-26-4, CIPAC 440.302; ≥ 990 g/kg on a theoretical dry technical material (TC) basis or 615–665 g/L in the technical concentrate (TK); N-methylpiperidine impurity ≤ 3 g/kg dry weight or ≤ 2 g/L in TK. Member States must pay attention to the specification of commercial production and personal protective equipment for operators. EFSA: N-methylpiperidine is more acutely toxic than mepiquat itself, but of no concern at this level; a method for it in the formulation is missing.
- Methods (EFSA): technical material — HPLC-MS/MS and a CIPAC method. Enforcement residue definition in food and feed of plant and animal origin — sum of mepiquat and its salts expressed as mepiquat chloride; HPLC-MS/MS, LOQ 0.01 mg/kg in all commodities, soil 0.01 mg/kg, surface and drinking water 0.1 µg/L, body fluids 0.05 mg/L. In air — ion chromatography, LOQ 0.0163 mg/m³. For risk assessment in animal products — sum of mepiquat and 4-hydroxy mepiquat (free and conjugated).
- Reference values (EFSA): ADI 0.065 mg/kg bw per day from a LOAEL of 13 mg/kg bw per day in the two-year rat study with a factor of 200 (in 2008 the ADI was 0.2); ARfD 0.3 mg/kg bw, AOEL and AAOEL 0.23 — from a NOAEL of 30 mg/kg bw per day in the developmental neurotoxicity study (thinner corpus callosum in pups at 60 mg/kg bw per day). Intake: 19 % of the ADI (NL toddler) and 5 % of the ARfD (wheat); for the uses from the MRL review — 21 % of the ADI and 17 % of the ARfD (cultivated fungi), with uncertainty about oyster mushrooms grown on wheat straw.
- Environment (EFSA): mepiquat chloride below 0.1 µg/L in groundwater; the second component of the formulation, ethephon, may exceed 0.1 µg/L under neutral and alkaline soils — in two of six FOCUS scenarios for grass and three of nine for cereals. Livestock and consumer exposure assessment not finalised because of residue data gaps (among others trials with mepiquat and ethephon on grass); a study on sublethal effects in bees is also needed.