Safety and efficacy of Mintrex®Zn (Zinc chelate of hydroxy analogue of methionine) as feed additive for all species

Following a request from the European Commission, the European Food Safety Authority was asked to deliver a scientific opinion on the safety and efficacy of a zinc chelate of the hydroxy analogue of methionine (Mintrex®Zn) as a feed additive for all species. Mintrex®Zn contains a minimum of 16 % zinc and 80 % hydroxy methionine analogue ((2-hydroxy-4-methylthio)butanoic acid, HMTBa), as shown from analyses of the product. It is intended to be used as a source of the essential trace element zinc. Zinc (in several forms) and HMTBa are already separately authorised as nutritional feed additives in the European Union. Mintrex®Zn can be considered as a bioavailable zinc source, comparable to another authorised inorganic source of zinc, for all animal species. The Panel on Additives and Products or Substances use in Animal Feed (FEEDAP) considers Mintrex®Zn as a new compound of trace elements which therefore requires demonstration of safety for the target species. Since no studies on the tolerance of target animals to Mintrex®Zn were provided, the FEEDAP Panel cannot conclude on the safety of the compound for target animals. No data on edible tissues and products deposition were provided other than for liver from chickens and milk from dairy cows fed Mintrex®Zn. From the limited available data, the FEEDAP Panel considers it unlikely that the use of Mintrex®Zn would alter zinc deposition in edible tissues/products compared to other zinc sources. Based on the data from acute toxicity and genotoxicity studies, the FEEDAP Panel considers that Mintrex®Zn does not introduce any additional toxicity compared to other sources of dietary zinc. With regards to consumer safety, the FEEDAP Panel retains zinc as the component of potential toxicological significance of Mintrex®Zn. A model calculation was made based on recent data on zinc intake, and a higher zinc deposition in tissues compared to authorised zinc sources, taken as a worst case scenario. The FEEDAP Panel also recognised that zinc in muscle tissue appears insensitive to zinc supplemented within authorised levels compared to liver and kidney. As a result, consumer exposure would not exceed the upper intake level for zinc (25 mg day-1). Therefore the FEEDAP Panel concludes that no concerns for consumer safety would result from the use of Mintrex®Zn in feed at the maximum authorised zinc levels. The FEEDAP Panel considers that Mintrex®Zn is safe for the user provided that protective measures are taken and that it does not represent additional risks to the environment compared to other sources of zinc for which it will substitute. The FEEDAP Panel made some recommendations with regards to the Register entry and highlighted the need for analytical methods specific to the determination of the chelates rather than the trace element.