Assessing Ecotoxicity of Size-fractionated Airborne Particulate Matter

Abstract

Particulate matter (PM) is grouped as coarse, fine, and ultrafine particles (UFPs) with aerodynamic diameters of 2.5 to 10 μm (PM10), <2.5 μm (PM2.5), and <0.1 μm (PM0.1), respectively. The course and fine fractions have been well characterised from numerous aspects, including potential environmental hazard. However, more and more studies are targeted to the UFP fraction, as they bind relatively higher concentrations of potentially toxic materials and they might penetrate through cell biological barriers, posing higher risk to the biota. In our study, ecotoxic potential of size-fractionated urban aerosol was evaluated, using the kinetic version of the Vibrio fischeri bioluminescence inhibition bioassay. The kinetic protocol makes it possible to avoid false ecotoxicity readings which might appear in case of coloured and/or turbid samples. Our results showed that all PM fractions elucidated significant toxic response, highest toxicity was experienced in the range of 0.25/0.5μm and 0.5/1 μm (with the EC50s of 7.07 and 7.8%). Ecotoxicity in general followed the typical pattern of number size distributions of submicron particles experienced in Europe.