Following a request from of the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver an opinion on the safety for the target animals, consumer, user and the environment and the efficacy of an additive made of bentonite and sepiolite. Bentonite is currently authorised as binder, anticaking and anticoagulant agent. Sepiolite is not authorised as food or feed additive. The applicant is seeking an authorisation for the mixture of both compounds (ToxFin® Dry) as an additive for the reduction of the contamination of feed by aflatoxin B1, at a recommended use level ranging from 0.1 to 2 % in complete feed.
The safety assessment of the additive is based on the separate consideration of its two constituents, bentonite and sepiolite. Bentonite is essentially not absorbed, is not genotoxic and of low systemic toxicity. No toxic effects of sepiolite were observed in a 12 week rat study when tested alone (1.5%) or in a 28 day study when tested as Toxfin® Dry (0.5%) by oral route. There is limited evidence that sepiolite is potentially carcinogenic by parenteral routes (inhalation, intrapleural and intraperitoneal). Carcinogenic potency in a series of studies that did not use the same route of administration varied according to geological origin of the three sepiolite samples tested. On the basis of the limited evidence from these studies, carcinogenic potency was positively associated with a maximum fibre length. There is inadequate evidence in experimental animals for the carcinogenicity of short sepiolite fibres (< 5 µm).No oral carcinogenicity study could be found. A limited selection of mutagenicity tests gave no clear indication of the genotoxicity of sepiolite.
The currently authorised maximum contents for montmorillonite and sepiolite when used individually (20 000 mg/kg complete feed) are considered safe for all animal species as derived from feeding studies with food-producing animals. In consequence, Toxfin® Dry would be safe for all animals species and categories up to a maximum concentration of 20 000 mg/kg complete feed.
Bentonite and sepiolite, in common with other clays, are not absorbed to any measurable extent. Consequently, it is unlikely that the consumption of edible tissues/products of treated animals would expose the consumer to harmful amounts of residues of any chemical component derived from Toxfin® Dry. The FEEDAP Panel considers that there is no concern for the safety of consumers of food products derived from animals fed diets containing the additive.
Dust generated from Toxfin® Dry during normal handling has the potential to expose the whole of the respiratory tract of users to potentially harmful substances (bentonite, sepiolite and crystalline silica) for which no safe levels of exposure have been identified. Measures must be taken to limit exposure of users to dust. In the absence of data for sepiolite, it would be prudent to treat ToxFin® Dry as a skin and eye irritant and a skin sensitiser.
Bentonite and sepiolite are naturally occurring clays widely distributed in the environment. Therefore, it is not expected that the use of the additive in animal nutrition would adversely affect the environment.
Since only one in vivo study in chickens has been provided, the FEEDAP Panel considers that there is insufficient evidence to conclude on the efficacy of the additive as a substance for reduction of contamination of feed with mycotoxins.