Safety and efficacy of L-lysine sulphate (Vitalys®Liquid and Vitalys®Dry) for all animal species

The European Food Safety Authority (EFSA) received a request from the European Commission for an opinion on the safety and efficacy of Vitalys®, an additive that consists of L-lysine sulphate and by products produced by fermentation by a specific strain of Corynebacterium glutamicum. The product is formulated as a liquid (minimum 25 % L-lysine) and a solid (minimum 44 % L-lysine). All the studies submitted have been made with Vitalys products which were not demonstrated to be identical to the product that is proposed to be placed on the market. The FEEDAP Panel concludes that Vitalys in both application forms (dry or liquid) contains bioavailable lysine. Vitalys is therefore considered a lysine source for all animal species. The applicant has provided two in vitro studies with Vitalys which may be considered to give sufficient reassurance that the product possesses no genotoxic potential in vitro. However, a 90-day study in rats has identified, in high dose treated animals, proliferative lesions in the urogenital tract which are not satisfactorily explained. In the absence of such an explanation the carcinogenic potential of the product cannot be excluded. Therefore the FEEDAP Panel is not in a position to conclude on the safety of Vitalys for the consumer. Although nothing in the data provided on the use of Vitalys in pigs and poultry suggested that Vitalys would pose a risk when used to satisfy lysine requirements, the data from the 90-day rat study does raise concerns for target animal safety. Both dry and liquid Vitalys are presumed to be potential respiratory sensitizers. The evidence of dermal sensitisation by dry Vitalys confirms the potential for user risk. Both the dry and the liquid Vitalys are required to be labelled as an irritant and marked “Xi”. Both products show no evidence of short term toxicity by inhalation. Without further data on the effects seen in rats after 90-days exposure, the potential for carcinogenicity cannot be excluded and the product should be handled accordingly. The FEEDAP Panel concludes that the use of Vitalys as feed additive is not expected to present a risk to the environment. The FEEDAP Panel recommends: i) that the Register entry should contain, under description, the exact strain (DSM 14764) of the Corynebacterium glutamicum used for fermentation; ii) that since the specification of the product tested in the 90-day study is within that of the product already authorised, the safety of that product should be reconsidered.