[Pathogenicity of artificial mineral fibers: are they as dangerous as asbestos?]

Man-Made Mineral Fibres (MMMF) are starting to replace asbestos in the insulation industry. The popularity of these fibres has increased since the demonstration, in man, of the fibrogenicity and carcinogenicity of asbestos. A fear of human toxicity of MMMF has followed the demonstration of toxicity in animals after injection or instillation. This review of the litterature discusses the toxicity and side effects of MMMF. These fibres seem to have less toxicity than asbestos for the following reasons: 1. A lower concentration of fibres found in the air of the MMMF industry. 2. The cleavage of fibres in a perpendicular and non-parallel way. 3. The dissolution of fibres in the lung. Very fine fibreglass and mineral wool seem to be more toxic than continuous filaments and ordinary fibreglass.