Of the ~400 fibrous minerals that are present in the natural environment, only
six were commercially used and regulated under the term “asbestos”. The carcinogenicity
of asbestos minerals has been largely demonstrated. Properties associated with mineral
fiber toxicity include structure, length/diameter ratio, surface area, and bio-persistence.
Unregulated mineral fibers that share similar properties are known or suspected of causing
similar hazards to asbestos, and specifically malignant pleural mesothelioma (MPM). For
example the fibrous serpentine antigorite in material used to pave roads has been correlated
to high MPM rates in New Caledonia. Erionite fibers present in material used for
construction has been associated with a MPM epidemic in Central Turkey, and was more
potent than asbestos in causing disease in animal experiments. The asbestiform amphiboles
winchite and richterite in the vermiculite mined in Libby, Montana, USA, caused an
epidemic of asbestos-related disease in workers and the local population. Potential
geological sources of fibrous minerals are numerous; they represent a hazard when soil
erosion and/or human activities disperse the fibers in places where they may be in contact
with population. Environmental exposure to these carcinogens is increasing due to the
development of population and human activities in rural areas; geological and
environmental investigations should be carried out before any mining, road-making and
other dust-producing activities in order to prevent from possible exposure to carcinogenic
mineral fibers.
Keywords: Amphibole, antigorite, asbestos, cancer, environment, erionite,
exposure, mineral fibers, serpentine.