AIR-POLLUTION LEVELS REFLECTED IN DEPOSITS ON BUILDING STONE

About 1400 samples of building stone have been collected in Sweden and other European countries, mainly from polluted areas but also from countryside districts. All samples have been analysed by SEM/EDS, and some selected by other techniques like XRPD, GC/MS, or ICP. In particular, we have determined concentrations of gypsum, iron and some other metals; chlorine, phosphorus, soot (carbon), and organic components. The results confirm a positive correlation between SO2 concentrations and gypsum formation on calcareous stone. Polluted areas generate more metal particles and particles of soot, asphalt, car-tyre rubber, fly-ash, quartz calcite, gypsum, and chlorides. On building facades in polluted cities about 100 constituents have been identified, including carcinogeneous organic compounds like benzopyrene.