Sorbic acid and its salts have been subjected to an extensive battery of tests, including acute, short-term and chronic toxicity/carcinogenicity tests, two-generation reproduction and teratogenicity studies. These studies show that sorbic acid and sorbates have a very low level of mammalian toxicity, even in chronic studies at up to 10% of the diet, and are devoid of carcinogenic activity. They are non-mutagenic and non-clastogenic in vitro and in vivo. The low toxicity is explicable by the fact that sorbic acid is metabolized rapidly by similar pathways to other fatty acids. In humans, a few cases of idiosyncratic intolerances have been reported (non-immunological contact urticaria and pseudo-allergy). The frequency appears low but there are too few reported data for an accurate assessment of the true incidence. In extreme conditions (high concentrations and temperature) sorbic acid may react with nitrite to form mutagenic products but these mutagens are not detectable under normal conditions of use, even in curing brines.