Exposure to Volcanic Ash on Montserrat, British West Indies

Abstract

The volcanic eruption on Montserrat has deposited ash on the island since 1995. The ash contains the crystalline silica mineral cristobalite, and there is concern about a possible silicosis risk. Measurements of the islanders’ exposure to the ash and cristobalite have been made since 1996. The islanders with the greatest exposure to airborne ash and cristobalite are gardeners working in the occupied areas of the island closest to the volcano, and Public Works staff and others involved in ash clearing operations. Some of these individuals may be at risk of respiratory illness if the volcanic eruption continues for many years to come. The preliminary results of a respiratory health survey of outdoor workers, carried out in 2001, did not show any evidence for the early development of silicosis. A concurrent study of Montserratians in the UK and an earlier study of Montserratian children did find evidence of an association between ash exposure an respiratory symptoms. There is a need to minimize the future exposure of the most highly exposed groups of islanders to minimize the long-term health risks.