Safety of cassia gum as a feed additive for cats and dogs based on a dossier submitted by Glycomer GmbH
The additive cassia gum consists mainly of high-molecular weight polysaccharides composed primarily of a linear chain of 1,4-b-D-mannopyranose units with 1,6-linked a-D-galactopyranose units. In 2014, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) delivered an opinion on the safety and efﬁcacy of cassia gum in cats and dogs. The Panel concluded, based on positive ﬁndings observed in a bacterial reverse mutation test with a semi-reﬁned cassia gum (about 70 mg anthraquinones/kg) but not with puriﬁed semi-reﬁned cassia gum that meets the speciﬁcation as a food additive (< 0.5 mg anthraquinones/kg), that only puriﬁed semi-reﬁned cassia gum that meets the speciﬁcations of cassia gum as a food additive can be considered safe for cats and dogs, at a maximum content of 1.5% cassia gum (15,000 mg/kg feed) in dry matter, corresponding to 1.32% (13,200 mg/kg feed) in a standardised complete feed with 12% water content. The conclusion was conﬁrmed in an opinion delivered by the Panel in 2017. Following this opinion, the European Commission gave the possibility to the applicant to submit complementary information on the safety for cats and dogs. The semi-reﬁned cassia gum under application was mutagenic in a bacterial reverse mutation test in Salmonella Typhimurium strain TA100. Positive results were also observed after heat sterilisation of the test item. Isopropanol puriﬁed semi-reﬁned cassia gum did not show mutagenic effect. Examination of various other cassia gum extracts did not identify any source of mutagenicity. The mutagenicity of the semi-reﬁned cassia gum under application cannot be excluded. Therefore, the FEEDAP Panel cannot establish the safety of semi-reﬁned cassia gum for cats and dogs.