2022年2月23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CCTCC M2020321生产的L-缬氨酸（l-valine）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，专家小组认为在拟议的使用条件下，该添加剂对目标物种、消费者和环境是安全的。评估中的添加剂被认为是非反刍动物物种氨基酸L-缬氨酸的有效来源。为了使补充的L-缬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 l-valine as a nutritional additive for all animal species. The production strain and its DNA were not detected in the final additive. Therefore, the final product does not give raise to any safety concern with regard to the genetic modification of the production strain. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concludes that l-valine produced using Escherichia coli CCTCC M2020321 is safe when supplemented in appropriate amounts to the diet according to the nutritional needs of the target species. The FEEDAP Panel has concerns on the use of amino acids in water for drinking for hygienic reasons, and due to the risk of imbalances when administered simultaneously via feed. The use of l-valine produced using E. coli CCTCC M2020321 in animal nutrition is considered safe for the consumers and for the environment. The FEEDAP Panel cannot conclude on the potential of l-valine produced using E. coli CCTCC M2020321 to be toxic by inhalation, irritant to the skin or eyes, or a dermal sensitiser due to the lack of data. The endotoxin activity of the additive does not represent a hazard for users handling the additive when exposed by inhalation. The additive l-valine produced by fermentation using E. coli CCTCC M2020321 is regarded as an efficacious source of the essential amino acid l-valine for non-ruminant nutrition. For the supplemental l-valine to be as efficacious in ruminants as in non-ruminant species, it requires protection against degradation in the rumen.
