Particle-bound PAHs and particle-extract-induced cytotoxicity of emission from a diesel-generator fuelled with soy-biodiesel

Abstract

This study investigates the size distribution of nano/ultrafine particle-bound PAHs (polycyclic aromatic hydrocarbons) and the PAH-associated carcinogenic potency/cytotoxicity of the exhaust from a generator that is fuelled with D100 (pure petroleum diesel) and S20 (v/v = 20% soy-biodiesel/80% D100) and operated at stable energy output loads (0 and 3 kW). A micro-orifice uniform deposit impactor (MOUDI) and a Nano-MOUDI (with aerodynamic diameters of 0.01- 18 μm) were used to collect PM samples. The cytotoxicity of the organic solvent extracts of PM samples to the human male monocytic cell strain (U937) was evaluated using the MTT (3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide) method. The results indicate that at both loads, using S20 in place of D100 effectively reduced the emissions of DEPs, PAHs in the DEPs, and PAHs-associated BaP eq; furthermore, the unit mass cytotoxicity of ultrafine particles and nano-particles in the DEPs was also lowered (by an average of 52.6%). Therefore, soybean biodiesel (S20) can be used as an alternative fuel to petroleum diesel to reduce the hazards of emissions from diesel engines to human health. © Taiwan Association for Aerosol Research.