TSCA Definition 2019: A complex residuum from the production of musk ambrette by the nitration of 1-(1, 1-dimethylethyl)-2-methoxy-4-methylbenzene. Composed primarily of 2-(1, 1-dimethylethyl)-5-methyl-2, 5-cyclohexadiene-1, 4-dione, 1-methoxy-5-methyl-2, 4-dinitrobenzene, and 1-(1, 1-dimethylethyl)-2-methoxy-4-methyl-5-nitrobenzene.