January 9, 2013

The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was requested by the European Commission to deliver a scientific opinion on the safety and efficacy of the hydroxy-analogue of selenomethionine (HMSeBA) as feed additive for all species.

The additive hydroxy-analogue of selenomethionine consists of synthetic R,S-2-hydroxy-4-methylselenobutanoic acid (HMSeBA) and is intended to be used as a source of the essential trace element selenium for all animal species/categories.

Data from tolerance studies on chickens and turkeys for fattening and piglets showed that the additive HMSeBA is a safe selenium source when used up to the maximum authorised total selenium content in complete feed. A safety margin of 10 was identified. Provided the maximum authorised total selenium content in complete feed is not exceeded, the use of HMSeBA as a selenium source is considered to be safe for all animal species/categories.

Based on a toxicology testing package (acute toxicity, genotoxicity in vitro and in vivo, repeated dose toxicity) it is concluded that HMSeBA does not elicit adverse unexpected effects for a selenium compound. After being absorbed, HMSeBA is metabolised to selenomethionine; consequently, no residues of the compound itself occur in animal tissues and products. Compared with inorganic selenium sources, the use of HMSeBA in animal nutrition would result in a similar increase in selenium deposition in animal tissues/products as that resulting from selenised yeast.

To ensure consumer safety from consumption of food originating from animals fed diets containing HMSeBA, the FEEDAP Panel concludes that dietary selenium supplementation from the additive should not exceed a maximum of 0.2 mg Se/kg complete feed.

The use of HMSeBA in feed does not pose an additional risk to the environment, compared with other sources of selenium for which it will substitute, as long as the maximum authorised content in feeding stuffs is not exceeded.

Studies in chickens for fattening and pigs for fattening showed an increased plasma/liver selenium level and plasma glutathione peroxidase activity in response to feed supplementation with HMSeBA. Therefore, the FEEDAP Panel concludes that HMSeBA is an efficacious source of the essential trace element selenium for animal nutrition. The use of the additive does not modify the quality of meat as measured by physico-chemical properties.