Aflatoxin G2-13C17is intended for use as an internal standard for the quantification of aflatoxin G2by GC- or LC-MS. Aflatoxin G2is a mycotoxin that has been found inAspergillus.1It is lethal to ducklings (LD50= 2.83 mg kg) but is non-toxic to rats when administered at a dose of 200 mg kg.2 1.Bennett, J.W., and Klich, M.MycotoxinsClin. Microbiol. Rev.16(3)497-516(2003) 2.Wogan, G.N., Edwards, G.S., and Newberne, P.M.Structure-activity relationships in toxicity and carcinogenicity of aflatoxins and analogsCancer Res.31(12)1936-1942(1971)