DETERMINATION OF 2-(4-MORPHOLINYL)BENZOTHIAZOLE IN ENVIRONMENTAL-SAMPLES BY A GAS-CHROMATOGRAPH EQUIPPED WITH A FLAME PHOTOMETRIC DETECTOR

2-(4-Morpholinyl)benzothiazole (24MoBT) exists in automobile tire rubb er as an impurity of a vulcanization accelerator and has been proposed as a potential molecular marker of street runoff (Spies, R. B.; Andre sen, B. D.; Rice, D. W., Jr. Nature 1987, 327,697-699. The present pap er describes an analytical method for 24MoBT in environmental samples (e.g., street dusts and river sediments) by gas chromatography. The me thod relies upon extraction with a 6:4 (v/v) mixture of benzene and me thanol, purification by acid extraction, and adsorption column chromat ography, followed by determination using capillary GC equipped with a sulfur-selective detector (i.e., FPD). The recovery of 24MoBT for the entire procedure was 85%, and the relative standard deviation for four replicated analyses was 1.5%. The detection limit was 0.08 ng injecte d 24MoBT, corresponding to 0.20 ng/g of dry sample. The selectivity an d sensitivity of the present method permit the determination of 24MoBT at the trace levels (e.g., similar to ng/g) encountered in environmen tal samples. 24MoBT concentrations in various environmental samples ar e also reported.