Non-occupational exposure to commercial amphibole asbestos and asbestos-related disease: is there a role for grunerite asbestos (amosite)?

An increase in the incidence of asbestos-related diseases in the general population from non-occupational exposure to the various asbestos fibre-types has been a concern since the identification of riebeckite asbestos (commonly referred to as blue asbestos or crocidolite in the medical literature) as an aetiological agent in human mesothelioma. Almost 40% of the mesotheliomas initially identified occurred near a mining operation in South Africa among individuals without an occupational history involving asbestos. As the various asbestos fibre-types shared a common commercial name the initial expectation was that the carcinogenic potency of all the asbestos fibre-types would be similar, if not identical. Urgency was added to these concerns as asbestos-related pleural changes were found elsewhere in the general population in certain geological locales and low concentrations of asbestos bodies began to be found with frequency in the lungs of the general population in a number of urban centres. The seminal studies since 1960 are reviewed to illustrate the potential for the commercial amphibole asbestos minerals to produce disease among individuals with non-occupational exposure, with particular attention to grunerite asbestos.