4-Methyl-2-phenylpent-2-enal (FL 05.100) removed from the Union list of flavourings: aneugenicity could not be ruled out, and producers submitted no data and declared that the substance is no longer used; EFSA — gene mutations (Big Blue) and clastogenicity (comet assay in the duodenum) ruled out for the representative substance, micronuclei in vitro by aneugenicity
Commission Regulation (EU) 2025/147, published on 30 January 2025, removes 4-methyl-2-phenylpent-2-enal (FL No 05.100, CAS 26643-91-4) from Part A of Annex I to Regulation (EC) No 1334/2008. The substance had been listed conditionally, with a footnote requiring EFSA to complete its evaluation. In its opinion of 29 June 2022 (FGE.216Rev2) EFSA concluded that the representative substance of the group, 2-phenylcrotonaldehyde (FL 05.062), acts by an aneugenic mode of action, and that the in vivo micronucleus studies were inconclusive — so potential aneugenicity cannot be ruled out for any substance in the group.
- The deleted entry (FEMA 1473, Council of Europe No 10366) permitted the substance in several dozen food categories with limits, e.g. up to 5.00 mg/kg in confectionery (5.2–5.4), breakfast cereals (6.3), bakery wares (7.1, 7.2) and protein products (12.9); 0.08 mg/kg in alcoholic beverages of categories 14.2.1, 14.2.2, 14.2.5 and 14.2.6; 0.09 mg/kg in category 4.2. Restrictions on its use had been introduced earlier, pending submission of data, by Regulation 2024/238 — but the interested operators did not submit the data.
- Transitional provisions: food with added FL 05.100 lawfully placed on the market before the regulation’s entry into force (twentieth day after publication) may stay on sale until its date of minimum durability or use-by date; the same applies to imported food if the importer shows it was already in transit to the EU. The exception does not cover the substance itself or flavouring preparations containing it that are not intended to be consumed as such.
- Tests in FGE.216Rev2 (2-phenylcrotonaldehyde as representative of five α,β-unsaturated 2-phenyl-2-alkenals of subgroup 3.3 of FGE.19): mutation assay at the cII locus in Big Blue® transgenic mice — negative; in vivo comet assay in duodenum cells of rats up to 700 mg/kg bw per day (estimated maximum tolerated dose) — negative; in vitro micronucleus test — micronuclei by an aneugenic mechanism; in vivo bone marrow micronucleus assays — inconclusive. Comparing the lowest aneugenic concentration in vitro with the use levels of 05.062 indicated a concern in several food categories.
- For the other four substances of the group (FL 05.099, 05.100, 05.175 and 05.222) EFSA anticipates aneugenicity based on structural similarity, but does not quantitatively transfer the lowest aneugenic concentration from 05.062 — data are needed for each of them individually. Until then none of the five substances can be assessed through the usual procedure for flavouring substances. The α,β-unsaturated aldehyde structure is a structural alert for genotoxicity.