PARTICLE SIZE DISTRIBUTION OF MONO-, TETRA-, AND OCTA-CHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS IN AMBIENT AIR DURING HAZE EPISODES

摘要

There are few studies on the levels and particle size distributions of lower chlorinated dibenzo-p-dioxins and dibenzofurans (such as mono-CDD/Fs; dibenzo-p-dioxins and dibenzofurans labelled DD/Fs) in the atmosphere, while lots of information on tetra- to octa-chlorinated homologues has been found. In this study, the distribution characteristics of mono-, tetra-, and octa-chlorinated dibenzo-p-dioxins and dibenzofurans in the different sizes of urban airborne particles during haze episodes were investigated. Tetra-, and octa-chlorinated DD/DFs were mainly in the particles and the concentrations both increased as the particle size decreased, which was not the case for the monochlorinated DD/Fs. it is necessary to consider the lower chlorinated homologues to improve our understanding of the environmental behaviour during haze episodes.