2024年4月10日，据欧盟食品安全局（EFSA）消息，应欧盟委员会要求，欧盟动物饲料添加剂和产品（FEEDAP）研究小组就大肠杆菌CGMCC 7.460生产的L-色氨酸（l-tryptophan）作为所有动物饲料添加剂的安全性和有效性发表科学意见。
经过评估，专家小组认为该添加剂对消费者和环境是安全的。在缺乏数据的情况下，专家小组无法就该添加剂作为皮肤、眼睛刺激物或皮肤敏化剂的可能性得出结论。评估中的添加剂被认为是非反刍动物物种氨基酸L-色氨酸的有效来源。为了使补充的L-色氨酸对反刍动物和非反刍动物同样有效，需要防止其在瘤胃中降解。部分原文报道如下：
Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of the feed additive consisting of l-tryptophan produced by fermentation with Escherichia coli CGMCC 7.460 when used as a nutritional additive in feed and water for drinking for all animal species and categories. The production strain is not genetically modified. Viable cells of the production strain were not detected in the final additive. The additive does not give rise to any safety concern regarding the production strain. The use of l-tryptophan (≥ 98%) produced with E. coli CGMCC 7.460 to supplement feed is safe for non-ruminant species. There may be a risk for an increased production of toxic metabolites when unprotected tryptophan is used in ruminants. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) has concerns on the safety of the simultaneous oral administration of l-tryptophan via water for drinking and feed due to possible amino acid imbalances and hygienic reasons. The use of l-tryptophan produced with E. coli CGMCC 7.460 in animal nutrition raises no safety concerns to consumers of animal products and to the environment. In the absence of data, the FEEDAP Panel cannot conclude on the potential of the additive to be irritant to skin or eyes, or on its potential to be a dermal sensitiser. The endotoxin activity of the additive in combination with the high dusting potential may represent a risk of exposure by inhalation to endotoxins for users. The additive l-tryptophan is regarded as an effective source of the amino acid l-tryptophan for all non-ruminant species. To be as efficacious in ruminants as in non-ruminants, it should be protected from ruminal degradation.
