Safety assessment of 2-ethyl-3,(5 or 6) dimethylpyrazine as a food ingredient.

ABSTRACT

2-Ethyl-3,(5 or 6)-dimethylpyrazine (CAS No. 27043-05-6), a heterocyclic, nitrogen-containing compound, is used in the food industry as a flavor ingredient for its characteristic roasted odor and flavor, reminiscent of roasted cocoa or nuts. Pyrazines, including 2-ethyl-3,(5 or 6)-dimethylpyrazine, are widely distributed in foods and because of their natural unavoidable occurrence in cooked food; therefore, pyrazine compounds, including 2-ethyl-3,(5 or 6)-dimethylpyrazine, are commonly consumed in the daily diet. 2-Ethyl-3,(5 or 6)-dimethylpyrazine is oxidized in rats almost exclusively via its aliphatic side-chain to carboxylic acid derivatives. The LD(50) of 2-ethyl-3,(5 or 6)-dimethylpyrazine in rats was reported as 460 mg/kg and it is reported to be irritating to the skin, eyes and the upper respiratory tract. Two 90-day rat feeding studies have been conducted on 2-ethyl-3,(5 or 6)-dimethylpyrazine, with the one reporting a no effect level of 12.5mg/kg/day (both sexes) and a second study reporting a NOAEL of 2-ethyl-3,(5 or 6)-dimethylpyrazine 17 and 18 mg/kg/day for male and female rats, respectively. Although no genotoxicity studies were found on 2-ethyl-3,(5 or 6)-dimethylpyrazine, structurally similar pyrazine derivatives were reported as clastogenic in mammalian cells and non-mutagenic in bacterial assays. The relevance of the positive results in assays with Saccharomyces cerevisiae and Chinese hamster ovary cells in vitro is unclear. The data and information available, including a prolonged history of safe use, indicate that at the current level of intake, the food flavoring use of 2-ethyl-3,(5 or 6)-dimethylpyrazine is safe.