Opinion of the Scientific Panel on Additives and Products or Substances used in Animal Feed on a request from the Commission on the safety of the product “Biomin BBSH 797” for piglets, pigs for fattening and chickens for fattening

The active ingredient of the product Biomin BBSH 797 is a strain of Eubacterium sp., originally isolated from bovine rumen. The bacterium was selected for its capacity to reduce to a less toxic form trichothecene mycotoxins commonly encountered as contaminants of cereal grain. The product therefore is intended to be applied to cereals to be used in animal feed that are contaminated (or presumed to be contaminated) with trichothecenes. The European Food Safety Authority has been requested by the European Commission to assess the safety of “Biomin BBSH 797” Microorganisms: Eubacterium sp. DSM 11798 for the piglets, pigs for fattening and chickens for fattening, for the user, the consumer of animal products and the environment. Because the strain of Eubacterium used in the Biomin product cannot be assigned to an existing species there is no historical information on its prevalence within the digestive tract of livestock (or humans). Consequently the degree of natural exposure to this or similar strains cannot be assessed. Under these circumstances the tolerance tests made with the target species assume a greater importance. Although no concerns were noted in any of the four tolerance studies (with piglets and chickens) in which the additive was supplied at ten-fold overdose, the design of the studies did not provide the capacity or power to detect such effects. In particular, the first two studies made with mouldy grain were confounded by the presence of mycotoxins and the results from these studies have to be treated with added caution. No tolerance studies were made in growing/fattening pigs for which a claim is made. Consequently, safety for any of the proposed target species has not been demonstrated. Numbers of the main groups of bacteria other than eubacteria contributing to the flora of the digestive tract in pigs and chickens were not significantly affected by the inclusion of the product at the recommended dose or in the case of piglets, ten-times the recommended dose. However, the studies did not include any counts of total eubacteria or strain DSM 11798, despite the availability of 16S rRNA probes which would have allowed enumeration. As a result the potential of the organism to colonise the digestive tract in competition with an existing eubacterial flora is unknown. There is some evidence from the seven efficacy trials presented that the product can lead to an improvement in relative growth performance, presumably by the reduction of a toxic effect. However, FEEDAP Panel remains concerned that, as efficacy is not conclusively established, reliance on the presumed efficacy of the product may lead to unsuitable feed material being treated and used with adverse consequences for the target species. FEEDAP Panel recognises that animal products make only a small contribution to the human exposure to trichothecenes and is satisfied that addition of the additive will not increase the total exposure of consumers to trichothecenes and their metabolites. However, it can not be assumed that the use of the product will reduce the risk. There is no reason to suppose the DSM 11798 isolate would present any specific or unique risks to those handling the additive. However, the product does contain proteinaceous material and so it is likely to pose a risk of sensitisation. Eubacteria are found as one of the major groups of bacteria in the digestive tract of livestock and humans and so are naturally occurring within the environment. Although little is known about the specific ecology of strain DSM 11798 it would be expected to behave as any other eubacteria and, as a strict anaerobe, would not be expected to survive in the wider environment.