Abstract

The inhalation of beryllium causes a serious lung disease characterised by pronounced radiographic and functional impairments and occurs in workers engaged in the extraction and manufacture of the metal. This paper describes the beryllium exposure levels and refining processes in a large beryllium factory operating since the 1930s. Lifetime beryllium exposure histories were estimated for the 309 workers present at a health survey conducted in 1977. Beryllium exposure levels in the plant were high for many years, with some estimated exposure levels in excess of 100 micrograms/m3. As late as 1975, there were exposures to beryllium above 10 micrograms/m3 in some jobs. After about 1977, the plant was in compliance with the permissible exposure limit of 2.0 micrograms/m3. The median cumulative exposure in this cohort was 65 micrograms/m3-years and the median duration of exposure was 17 years. From these data a series of exposure parameters, functions of the exposure histories that characterise biologically important dimensions of exposure were calculated for each worker.