Overview of Risk of Exposure

Beryllium disease was first noted in the 1930s in Europe. In the 1940s, reports of disease related to beryllium surfaced among workers exposed to beryllium-containing phosphors in the fluorescent lamp industry and the nuclear weapons industry (Kress and Crispell 1944). Industry standards and environmental controls for beryllium were initially established in the late 1940s.

At least 134,000 current U.S. workers are estimated to be exposed to beryllium, though precise numbers for the total number of workers exposed to beryllium are unavailable (Henneberger et al. 2004). This count does not include former workers, contract workers, and construction workers exposed in beryllium using facilities. Outside the United States, more and more industries are being identified with current or former beryllium exposure (Newman et al. 2005; Glazer and Newman 2003).

Occupational Exposure

Risk to workers depends considerably on their work tasks. For example, machinists in both ceramics and nuclear weapons manufacture have been found to have an increased risk of developing sensitization. This is probably due to small respirable particles of beryllium (<10 microns) that may be better able to deposit deep in the lungs. Other studies have shown that laboratory workers and construction workers in beryllium-using facilities are also at increased risk. However, numerous individuals with apparently trivial exposure, such as security guards, secretaries, and bystanders, have also developed disease. This suggests that a linear dose response may be absent. Inhaling metallic beryllium, beryllium oxide, beryllium-copper and other alloys, or beryllium salts are the major exposure risks leading to disease (Martyny et al. 2000; Sawyer et al. 2002; Willis and Florig 2002).

In What Industries Might Workers Be Exposed to Beryllium?

Industries and occupations with potential beryllium exposure include

• aerospace,
• automotive parts,
• computers,
• construction trades,
• dental supplies and prosthesis manufacture,
• electronics,
• industrial ceramics,
• laboratory workers,
• metal recycling,
• mining of beryl ore (beryl ore extraction),
• nuclear weapons,
• precision machine shops,
• smelting/foundry,
• tool and die manufacture, and
• welding.

Beryllium Sensitization

Beryllium sensitization (BeS) is found in 1% - 16% of exposed workers tested with the blood Beryllium Lymphocyte Proliferation Test (Saltini et al. 2001; Henneberger et al. 2001). Individuals may have BeS without disease, which is not associated with any symptoms or clinical abnormalities in pulmonary function tests or chest radiography. These individuals have a risk of developing chronic beryllium disease (CBD) in the future at a rate of 6% to 8% per year (Newman et al. 2005). In addition to total beryllium mass, factors such as chemical composition, particle size, number, and surface area may influence bioavailability of beryllium and contribute to risk of sensitization and disease (Henneberger et al. 2001; Stefaniak et al. 2004; Deubner et al. 2001).

Chronic Beryllium Disease (CBD)

CBD is typically considered only when there is known work exposure; however, CBD has also occurred in occupational and environmental settings where exposure was unexpected (Middleton 1998). Many individuals have developed BeS and CBD working in areas where air concentrations are found to be below the recommended workplace exposure limits (Maier 2001). Sensitization and disease has been reported in security guards, secretaries, and custodial staff who work at facilities using beryllium (Frome et al. 2003). CBD due to secondary contamination has been caused by exposure to beryllium from a workers' clothing (Newman and Kreiss 1992). BeS and CBD have been diagnosed among individuals living near beryllium-using facilities from which they received high exposures in the past.

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