Chemical Characterization and Toxicologic Evaluation of Airborne Mixtures. Chemical and Physical Characterization of Diesel Fuel Smoke

Diesel fuel no. 2 (DF2) used in the vehicle engine exhaust smoke system (VEESS) has been chemically and physically characterized. A battery of fractionation procedures was used, including elemental analysis, inductively coupled plasma, UV/visible and infrared spectrometrys, high performance liquid chromatography (HPLC), gas chromatography and GC/MS. The best overall characterization was provided by HPLC, which yielded four major fractions (saturated hydrocarbons, 70 percent; substituted benzenes, 16 percent; 2-ring aromatics, 12 percent; and 3-ring aromatics, 2 percent) and one minor fraction (polar aromatics, 0.2 percent). These fractions were further analyzed by GC/MS. No single component accounted for more than about one percent of the DF2. The major effect of aerosolization of the DF2, in a generator designed to simulate the military deployment of VEESS smoke, was partitioning of constituents between the vapor and the liquid particulate phase on the basis of their relative volatility. No significant levels of constituents not found in the unaerosolized DF2 were observed in the liquid phase of the smoke generated from it.