Toxicity of Mount St. Helen's Volcanic Ash and Relevance to Mining Populations.
Green-FH; Dollberg-D; Tucker-JH; Kiessling-P
Health Issues Related to Metal and Nonmetallic Mining 1983:105-121
The public health implications of exposure to volcanic ash following the eruption of Mount St. Helen's were reviewed. The population potentially exposed to respirable particles was over one million. Initial exposures in some areas were estimated to be as high as 35mg/m3 of total suspended particulates. Loggers and farmers are the occupational groups which face potential low level, long term exposure. Research initiated by the National Institute for Occupational Safety and Health (NIOSH) included surveillance of the acutely exposed populations, mineralogical analysis of the ash, ash toxicity studies, and autopsy and epidemiological studies on exposed populations. An excess of eye complaints and acute respiratory symptoms such as shortness of breath, wheezing, and coughing were initially noted in areas of heaviest ash fall. The eye complaints persisted for several months following exposure. Analysis of the ash indicated that most particles were in the respirable range, and estimates of the crystalline silica content ranged from 2.8 to 6.6 percent. This is of concern because of the potential of this material to cause silicosis. Laboratory studies suggested that volcanic ash has low toxicity to alveolar macrophages, but can produce subtle depressions in macrophage function. Preliminary studies also suggested that volcanic ash is moderately fibrogenic. Autopsies on 25 victims of the eruption showed that most died due to asphyxia by volcanic ash. Two victims who died within 16 days of the eruption had acute alveolar injury. The authors conclude that volcanic ash has a moderate potential to cause pneumoconiosis in heavily exposed populations.
Volcanic-ash; Acute-exposure; Long-term-exposure; Health-hazards; Occupational-exposure; Epidemiology; Respirable-dust; Logging-workers; Silica-dusts; Fibrogenicity; Environmental-exposure; Laboratory-testing; Pulmonary-system-disorders;
Wagner-WL; Rom-WN; Merchant-JA;
Asthma and Chronic Obstructive Pulmonary Disease; Disease and Injury; Pulmonary-system-disorders;
Health Issues Related to Metal and Nonmetallic Mining