Determining High-Concentration Aromatic Compounds in Gasolines (ASTM D5769) Using CG-TOFMS 2016Determining High-Concentration Aromatic Compounds in Gasolines (ASTM D5769) Using CG-TOFMSASTM D5769 is a widely accepted standard method used in the petroleum industry for determination of benzene, toluene, and total aromatics in finished gasolines by GC-MS. A common difficulty encountered with this method is the concern with saturation of the ion source, which leads to nonlinearity in calibration curves, especially for the quantification of the high-concentration aromatics, such as toluene.