The word "asbestos" is used to designate the main commercial types of asbestos (chrysotile, crocidolite, amosite) but there exist numerous asbestiform fibrous minerals, which are commercially valueless but widespread at the surface of the earth. Among them zeolite has already created health hazards in Turkey. Measurement of fibres in air and in tissues can contribute to a better knowledge of lung and body fibre burden associated with diseases. Among fibre-related diseases, studies have recently focused on clinical, epidemiological and pathogenic aspects of pleural fibrosis and lung or pleural cancer. At present the roles of the different types of fibres in the genesis of these diseases remain controverted. However, tobacco smoke associated with inhaled asbestos fibres provokes a multiplied risk of lung cancer. Regarding asbestos there exist regulations in most industrial countries designed to protect workers and diminish environmental pollution.