Beryllium was used as an agent to prolong the life of fluorescent light bulbs in the 1930s but was found to be a cause of acute and chronic berylliosis in the mid 1940s. An investigation by Hardy (33) of a large number of cases of sarcoidosis in Salem, Massachusetts resulted in establishing the cause and effect relationship. Beryllium exposure from fluorescent light bulb production has ceased, but copper-beryllium alloy exposures occur during the production and grinding of springs and electrical switches and in work on beryllium oxide ceramic materials in jet and rocket engines and nose cones.
Workers in dental laboratories are exposed to the fine powder that may be produced while finishing and polishing beryllium metal alloys. For the most part, the acute form of beryllium lung disease has been eliminated by strict environmental controls. It is almost always responsive to cessation of exposure or corticosteroid therapy.
Chronic berylliosis is a granulomatous disorder caused by a cell-mediated immune reaction to beryllium (34). Generally, a direct relationship exists between airborne beryllium levels and acute berylliosis but not for chronic berylliosis. The reason for this remained puzzling until the development of bronchoalveolar lavage in the late 1980s, which demonstrated that lung cells from patients with chronic beryllium disease would proliferate in the presence of beryllium salts (34).
Excessive production and accumulation of helper T-lymphocytes in the lungs occurs in the cell-mediated immune granulomatous process (35). Dyspnea is the most common symptoms, and crackles occur in 20% of patients. The vital capacity and diffusing capacity are decreased, and the radiograph shows small reticular-nodular opacities throughout the lungs and occasional hilar lymphadenopathy.
The illness is indistinguishable from sarcoidosis. Chronic beryllium disease can be confirmed by testing of the peripheral blood or lung cell proliferative response to beryllium (34). The lowest dose of corticosteroid therapy should be used. Beryllium is eliminated from the lungs slowly; thus, patients may have to take corticosteroids indefinitely. Corticosteroid therapy may reduce inflammation, possibly by suppressing the immune response to beryllium, but has no effect on the scarring. Prevention of exposure and continual education of individuals using beryllium products remain essential for elimination of the disorder.
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