L-threonine from Escherichia coli CCTCC M 2024477: IEC-VIS/FLD according to EN ISO 17180, endotoxins in batches 30 000–300 000 IU/g, user exposure up to 1 600 IU/m³
Commission Implementing Regulation (EU) 2026/1017, published on 8 May 2026, authorises until 28 May 2036 L-threonine (at least 98 % DM) from genetically modified E. coli CCTCC M 2024477 for all animal species, in feed and water for drinking. In the Polish version of recital 4 EFSA’s concerns about use in water for drinking refer to “L-threonine sulphate”, in the English version to L-threonine.
- Methods: identification according to the Food Chemicals Codex monograph; determination in the additive — ion-exchange chromatography with post-column derivatisation and optical detection (IEC-VIS/FLD) according to EN ISO 17180; in premixtures IEC-VIS/FLD (EN ISO 17180) or IEC-VIS according to Regulation (EC) No 152/2009; in compound feed IEC-VIS (152/2009); in water for drinking IEC-VIS or IEC-VIS/FLD. Endotoxins — Ph. Eur. 2.6.14.
- EFSA data (5 batches): threonine 99.9–100 % DM, loss on drying 0.05–0.07 % (water specification ≤ 0.2 %), specific optical rotation −28.2 to −28.6° (Ph. Eur. −27.6 to −29.0°). In 3 batches lead 0.012–0.022 mg/kg, antifoaming agent < 10 mg/kg, mycotoxins below the limits of detection. No DNA of the strain was detected (limit of detection 0.1 ng/g).
- Endotoxins in 3 batches 30 000–300 000 IU/g, dusting potential 1 215.5–1 365.5 mg/m³ (Stauber-Heubach). Recovery: in a vitamin–mineral premixture 79–96 % after 6 months, in piglet feed 92–99 % after 2 months, in water 100 % after 48 h; coefficient of variation of threonine in pelleted feed 4.4 %.
- EFSA considered inhalation likely and advised minimising endotoxin exposure; it drew no conclusions on skin and eye irritation or skin sensitisation. The act: only rumen-protected threonine for ruminants, a label warning on the supply of essential amino acids when given in water, endotoxin exposure ≤ 1 600 IU/m³, skin, eye and respiratory protection.