Metal Allergy: Beryllium

Abstract

Beryllium is one of the lightest metals, with unique mechanical, physical, and nuclear properties that allow major applications in the aircraft and aerospace industries as well as for nuclear reactors and defense. An estimated 300,000 workers are exposed to beryllium during ore extraction, processing, and manufacturing. Potential toxicities include acute and chronic beryllium disease (CBD) and lung cancer. Skin manifestations include irritant and allergic contact dermatitis, chemical ulcers, and ulcerating and dermal granulomas. Diagnosis of CBD includes (1) a history of beryllium exposure, (2) a positive lymphocyte proliferation test (BeLPT) either from blood or bronchoalveolar lavage, and (3) compatible pathology on lung biopsy. Beryllium sensitization (BeS) occurs with (1) and (2) in the absence of lung pathology. The BeLPT has been the cornerstone of both medical surveillance and the diagnosis of BeS and CBD and, in the occupational and pulmonary settings, has mostly replaced the beryllium patch test because of multiple reports of patch test sensitization. Contact stomatitis to dental alloys has been reported in the more recent dermatology literature, with beryllium patch testing recommended primarily on an aimed rather than a screening basis. Determinants of progression from BeS to CBD are uncertain, but higher beryllium exposures and the presence of a genetic variant in the HLA-DP β-chain appear to increase the risk. The US Occupational Health and Safety Administration has just issued a new permissible exposure limit (PEL) standard dramatically reducing the allowed workroom air concentration of beryllium. In addition, standard industrial hygiene controls including personal protective clothing and equipment are required since the PEL for beryllium does not always protect workers from dermal exposure and skin sensitization.