Scientific Opinion on the safety and efficacy of methionine-zinc, technically pure as amino acid for ruminants, and as compound of trace element for all species


nutritional additive, amino acid, compound of trace elements, methionine-zinc, safety, efficacy
First published in the EFSA Journal
23. Januar 2013
11. Dezember 2012
Last Updated
4. Februar 2013. This version replaces the previous one/s.
Opinion of the Scientific Committee/Scientific Panel

The additive methionine-zinc, technically pure (Met-Zinc) is zinc chelated with methionine in a molar ratio 1:2. It is intended to be used as a source of the amino acid in ruminants, and as compound of trace element for all species. The additive is safe for all animal species/categories considering that its use in supplementing feed is first limited by the regulatory maximum content of zinc. However, its contribution to dietary methionine needs consideration when formulating diets. The use of the additive will not modify the methionine content in tissues/products. Zinc from Met-Zinc would not lead to higher zinc deposition in tissues/products, and hence consumer exposure, than zinc from other authorised sources. The use of Met-Zinc in animal nutrition is safe for consumers when used up to the maximum authorised zinc level. In the absence of data, the compound should be considered as a potential irritant to skin and eye and skin sensitiser. Zinc compounds are hazardous by inhalation; Met-Zinc shows high dusting potential, thus exposure by inhalation represents a hazard to persons handling the additive. The use of Met-Zinc in feed as a source of zinc does not pose an additional risk to the environment, compared with other sources of zinc for which it will substitute, as long as the maximum authorised content in feedingstuffs is not exceeded. Methionine from the additive does not represent a risk to the environment. Based on data from a balance study on piglets and from a study on zinc tissue deposition in broilers, Met-Zinc is considered an efficacious source of zinc for all animal species/categories. The weak evidence seen for Met-Zinc is insufficient to conclude on its efficacy in ruminants; however, considering also an EFSA opinion on DL-Met, the Panel concludes that Met-Zinc has some potential as an effective source of methionine for ruminants.

Panel members at the time of adoption
Gabriele Aquilina, Alex Bach, Vasileios Bampidis, Maria De Lourdes Bastos, Gerhard Flachowsky, Josep Gasa-Gasó, Mikolaj Antoni Gralak, Christer Hogstrand, Lubomir Leng, Secundino López-Puente, Giovanna Martelli, Baltasar Mayo, Derek Renshaw, Guido Rychen, Maria Saarela, Kristen Sejrsen, Patrick Van Beelen, Robert John Wallace and Johannes Westendorf
Panel on Additives and Products or Substances used in Animal Feed
EFSA Journal 2013;11(1):3038 [25 pp.].
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