Efficacy and safety of L-valine from a modified E.coli K12 for all animal species
Following a request from the European Commission, the European Food Safety Authority was asked to deliver a scientific opinion on the efficacy and safety of the product L-valine for all animal species. L-valine is produced by a genetically modified E. coli K-12 strain. The introduced genes do not trigger any particular safety concerns. The final product does not contain any cultivable producer organism and the level of the newly introduced DNA is below the limit of detection of the method used. L-valine feed grade is a source of L-valine intended to supplement valine from natural sources. Based on the study with piglets provided, L-valine feed grade is considered as a source of available valine for all animal species. The minimum specification used by the applicant (L-valine content not less than 95 %) does not correspond to a highly purified product and therefore a tolerance study is required in at least one animal species. A tolerance study with piglets was provided. However the test material was considered unrepresentative and the duration of the study was too short. A conclusion on the safety of the product as currently specified for the target animals could not be drawn. L-valine with a high purity (>98 % valine) was shown to be non-mutagenic and nonclastogenic. A sub-chronic toxicity study and a reproduction study made with the same test item indicated that the additive was devoid of adverse effect in the rat for doses up to 1 % in the diet. L-valine feed grade (>98 % valine) was not irritating for skin or eyes and proved not to be a skin sensitizer. There is no evidence for acute toxicity by inhalation route at the maximum achievable concentration. It is considered that L-valine feed grade with a high degree of purity (not less than 98 %) is safe for target animals, consumers, users and the environment. However, if the minimum specification of 95 % L-valine is retained by the applicant, then additional evidence on safety for target animals and toxicological studies, including a 90-day study, supporting the safety for the consumer and the user would be required. Specific post-marketing monitoring of ‘L-valine – Feed Grade’ is not considered necessary. Some recommendations for changes to the register entry are made.