Indoor PM10 in university classrooms: Chemical composition and source behaviour

The indoor atmosphere of five university environments, ranging from a research laboratory to a vast lecture hall, was studied during a seven-week measurement campaign. The study was carried out in real-world conditions and was designed to distinguish periods when the environments were occupied from periods when they were empty. A comprehensive chemical characterisation of PM10 was carried out (elements as total, extractable and residual fractions, ions, elemental carbon, organic carbon), which allowed the study of the main PM sources (soil, sea, secondary inorganic species, traffic emission, organics). Other sources (heavy oil combustion, biomass burning and non-exhausts traffic emission) were well traced by the extractable or residual fractions of some elements (V, Rb, Mo).