Evaluation of physical health effects due to volcanic hazards: human studies.

Abstract

Despite certain gaps in the knowledge that has been gained from the studies done in the aftermath of Mount St. Helens and following previous major volcanic eruptions, we can be confident that the health effects of both short- and long-term exposures to the relatively low levels of airborne volcanic ash that are typical following such a volcanic eruption are minor. These effects seem to relate more to the irritating effect of the ash on mucous membranes and airway epithelia than to the potential of the ash (due to its free crystalline silica content) to initiate a fibrotic response. Nevertheless, common sense dictates that exposures should be minimized whenever possible by use of appropriate preventive measures, such as wetting the sedimented ash before disturbing it, and using commercially available disposable paper masks meeting NIOSH code TC-23 for dusts for light exposures and industrial half- and full-faced respirator and goggles for more extensive and heavy exposure.