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. 2002 Aug;59(8):523–531. doi: 10.1136/oem.59.8.523

Assessment of the exposure of islanders to ash from the Soufriere Hills volcano, Montserrat, British West Indies

A Searl 1, A Nicholl 1, P Baxter 1
PMCID: PMC1740338  PMID: 12151608

Abstract

Background and Aims: The Soufriere Hills volcano, Montserrat, has been erupting since July 1995 and volcanic ash has fallen on the island throughout most of the eruption. The ash contains substantial quantities of respirable particles and unusually large amounts (15–20%) of the crystalline silica mineral, cristobalite. The purpose of the surveys described here, undertaken between December 1996 and April 2000, was to determine levels of personal exposure of islanders to volcanic ash and cristobalite in order to inform advice on the associated risks to health and the measures required to reduce exposure.

Methods: Surveys of personal exposure to respirable dust and cristobalite were undertaken using cyclone samplers. In addition, direct reading instruments (DUSTTRAK) were used to monitor ambient air concentrations of PM10 at fixed sites and also to provide information about exposures to airborne particles associated with selected activities.

Results: Environmental concentrations of airborne ash have been greatest in the areas where the most ash has been deposited and during dry weather. Individual exposure to airborne ash was related to occupation, with the highest exposures among gardeners, cleaners, roadworkers, and police at roadside checkpoints. During 1997 many of these individuals were exposed to concentrations of cristobalite that exceeded the ACGIH recommended occupational exposure limit. Since the population became confined to the north of the island in October 1997, even those in relatively dusty occupations have received exposures to cristobalite well below this limit.

Conclusions: Most of the 4500 people who have remained on island since the eruption began have not been exposed to sufficiently high concentrations of airborne dust for long enough to be at risk of developing silicosis. However, more than a dozen individuals continued to experience frequent high occupational exposures to volcanic ash, some of whom may have had sufficient exposure to crystalline silica to be at risk of developing mild silicosis. If volcanic activity were to deposit further ash over the occupied areas of the island during the coming years, the risks of silicosis will become more substantial.

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Selected References

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  1. Baxter PJ, Bonadonna C, Dupree R, Hards VL, Kohn SC, Murphy MD, Nichols A, Nicholson RA, Norton G, Searl A. Cristobalite in volcanic ash of the soufriere hills volcano, montserrat, british west indies . Science. 1999 Feb 19;283(5405):1142–1145. doi: 10.1126/science.283.5405.1142. [DOI] [PubMed] [Google Scholar]
  2. Buist A. S., Bernstein R. S., Johnson L. R., Vollmer W. M. Evaluation of physical health effects due to volcanic hazards: human studies. Am J Public Health. 1986 Mar;76(3 Suppl):66–75. doi: 10.2105/ajph.76.suppl.66. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Hemenway D. R., Absher M. P., Trombley L., Vacek P. M. Comparative clearance of quartz and cristobalite from the lung. Am Ind Hyg Assoc J. 1990 Jul;51(7):363–369. doi: 10.1080/15298669091369790. [DOI] [PubMed] [Google Scholar]
  4. Hnizdo E., Sluis-Cremer G. K. Silica exposure, silicosis, and lung cancer: a mortality study of South African gold miners. Br J Ind Med. 1991 Jan;48(1):53–60. doi: 10.1136/oem.48.1.53. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Martin T. R., Wehner A. P., Butler J. Evaluation of physical health effects due to volcanic hazards: the use of experimental systems to estimate the pulmonary toxicity of volcanic ash. Am J Public Health. 1986 Mar;76(3 Suppl):59–65. doi: 10.2105/ajph.76.suppl.59. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Miller B. G., Hagen S., Love R. G., Soutar C. A., Cowie H. A., Kidd M. W., Robertson A. Risks of silicosis in coalworkers exposed to unusual concentrations of respirable quartz. Occup Environ Med. 1998 Jan;55(1):52–58. doi: 10.1136/oem.55.1.52. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Muir D. C., Julian J. A., Shannon H. S., Verma D. K., Sebestyen A., Bernholz C. D. Silica exposure and silicosis among Ontario hardrock miners: III. Analysis and risk estimates. Am J Ind Med. 1989;16(1):29–43. doi: 10.1002/ajim.4700160105. [DOI] [PubMed] [Google Scholar]
  8. Sanders C. L., Conklin A. W., Gelman R. A., Adee R. R., Rhoads K. Pulmonary toxicity of Mount St. Helens volcanic ash. Environ Res. 1982 Feb;27(1):118–135. doi: 10.1016/0013-9351(82)90063-9. [DOI] [PubMed] [Google Scholar]
  9. Wehner A. P., Dagle G. E., Clark M. L. Lung changes in rats inhaling volcanic ash for one year. Am Rev Respir Dis. 1983 Nov;128(5):926–932. doi: 10.1164/arrd.1983.128.5.926. [DOI] [PubMed] [Google Scholar]
  10. Wilson M. R., Stone V., Cullen R. T., Searl A., Maynard R. L., Donaldson K. In vitro toxicology of respirable Montserrat volcanic ash. Occup Environ Med. 2000 Nov;57(11):727–733. doi: 10.1136/oem.57.11.727. [DOI] [PMC free article] [PubMed] [Google Scholar]

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