[Atmospheric asbestos pollution in the urban environment: Milan, Casale Monferrato, Brescia, Ancona, Bologna and Florence].

The atmospheric concentrations of asbestos fibres were measured in 6 towns by long term sampling of air (3 weeks) and by counting at TEM both long and short fibres. Chrisotile and amphiboles were separately counted. For each town high traffic, low traffic and no traffic zones were considered as well as industrial areas and areas with possible and probable sources of asbestos pollution. For Milano the seasonal variations in atmospheric concentrations of asbestos fibres were also recorded in a central square. The maximum concentrations of total fibres was found in Milano (251.7 fibres/liter) and the minimum in Bologna (0.3 fibres/liter). Chrisotile and ultrashort fibres are the most frequent component of the atmospheric pollution. The fibre counts to which people is exposed are far below the levels at which it has been possible to detect risks in industry: however the possibility of a synergism between asbestos and other pollutants with consequent increase of the total carcinogenic potential of the polluted atmosphere cannot be ruled out. The control of the most active sources of asbestos dispersion must be considered in a correct balance between costs and social benefits.