Liquid or solid. (a) nonlonic ethoxylated (five (CH2)(2)O (EO) groups) nonylphenol, (b) anionic Na tetrapropylenebenzene-sulfonate, and (c) cationic benzethonium chloride (p-tert-octylphenoxyethoxyethyidimethylbenzylammonium chloride), 10-50 mg each, were preheated to 225degreesC and pyrolyzed at 770degreesC. The pyrolyzates were chromatographed in a SE-52 (ULTRA-2) 25 mx0.2-mm fused-silica column (10degreesC/min over 70-290degreesC) and MS spectra were recorded for the components isolated. Component A in pyrolyzate a was found to be H19C9C6OCH2CH2OCH2CH2OH. Component B in pyrolyzate b was a branched alkylbenzene C6H5C12H25; other components included unsaturated C-4-C-7 hydrocarbons + SO2, propylene dimer, a-methylstyrene, phenylbutene, compounds of M = 150, and 1,1'-dimethylnonyl-, tetrapropyl-, and 1,1'-dimethyltetradecylbenzenes. Pyrolyzate c contained CH3Cl, C6H5CH2Cl, (H3C)(3)CCH2C(CH3)(2)C6H4OCH2CH2OCH2CH2N(CH3)(2), and (H3C)(3)CCH2C(CH3)(2)C6H4OCH2CH2OCH2CH2N(CH3)CH2C6H5. Such products are characteristic and enable mini-amounts of surfactants to be analyzed and identified.