VERMICULITE - A REVIEW OF THE MINERALOGY AND HEALTH-EFFECTS OF VERMICULITE EXPLOITATION

Vermiculite is a mica type mineral that is being used in increasing qu antities for insulation, in composite cements, and in horticulture. No serious health risks have been found resulting from the exposure to v ermiculite alone nor are any anticipated in view of its long-term chem ical durability, even with respect to fibers of vermiculite. Vermiculi te ores may contain a variety of other minerals including asbestos, wh ich, if present in significant quantities, could pose a health risk to producers and end users. A variety of regulations are in place that s hould prevent inadvertent exposure to asbestos in vermiculites, but gr eat care is needed if true asbestos hazards are to be correctly identi fied. At the same time, vermiculites containing any of a variety amphi bole minerals should not be excluded from use because of mistaken iden tification of these minerals as asbestos. A variety of test methods th at have been developed are described and recommendations are made with respect to appropriate action levels for asbestos in vermiculites or other raw materials. (C) 1995 Academic Press, Inc.