Beryllium is a naturally occurring metal and is not radioactive. Because of its properties, beryllium has been part of the atomic energy and nuclear weapons industries since the 1940s. Exposure to beryllium and certain beryllium compounds can result in beryllium sensitization, which may develop into a disease of the lungs called chronic beryllium disease (CBD). Beryllium sensitization is an "allergic" condition to beryllium that can develop primarily after a person breathes air containing beryllium mists, dusts, and fumes. Even brief or small exposures to beryllium can lead to sensitization and/or CBD. However, most people exposed to beryllium will NOT get the disease. Other beryllium-related disorders can affect the skin, liver, spleen, heart, eye, or kidney. These disorders often occur in the presence of CBD.
Medical screening for beryllium sensitization and CBD usually begins with a Beryllium Lymphocyte Proliferation Test (BeLPT). The BeLPT is a laboratory blood test that examines how a type of disease-fighting blood cells that are normally found in the body, called lymphocytes, reacts to beryllium. In general terms, the BeLPT is performed by culturing lymphocytes from peripheral blood. If these lymphocytes react to the beryllium in a specific way, the test results are "abnormal." Individuals with an abnormal BeLPT are encouraged to file a claim with the Department of Labor Energy Employees Occupational Illness Compensation Program Act. If they do not react to beryllium, the test is "normal." The results are reviewed by a certified doctor (M.D. or Ph.D.) and are then mailed to the individual.
An abnormal BeLPT result indicates that the immune system has responded to beryllium and the individual being tested may have beryllium sensitization. As with other medical diagnostic tests, an abnormal test result should be confirmed. Beryllium sensitization is diagnosed by an occupational medicine physician based on abnormal BeLPT results.
Depending on numerous factors, including the frequency and amount of beryllium exposure and the type of exposure (metal, metal oxides, salts), 2 to 6% of beryllium-exposed people will develop beryllium sensitization and/or beryllium disease. However, certain work tasks with direct exposure (machining, welding) have been associated with beryllium sensitization rates as high as 20%. Even very small amounts of exposure to beryllium can cause disease in some people. Individuals still remain at risk of developing beryllium sensitization and CBD after exposure to beryllium has stopped, even if an initial BeLPT result was normal. Therefore, re-testing for beryllium sensitization is recommended approximately every three years, unless unexplained pulmonary symptoms develop, which would suggest that immediate re-testing is necessary. Re-testing is no longer necessary after four consecutively normal BeLPT results and no additional opportunity for beryllium exposure has occurred.
If beryllium sensitization is identified, physicians who specialize in the diagnosis and treatment of CBD should be consulted with regard to a diagnosis of beryllium sensitization and/or CBD. Specialized treatment can be very effective in controlling CBD; however, a complete cure with or without treatment is rare. Individuals who have beryllium sensitization, but do not yet have the disease, do not need treatment. Beryllium has been shown to cause cancer in humans and in many species of animals, although the studies suggesting the human association are limited. Regardless of the limitations of the studies performed, beryllium has been classified as a human carcinogen by the International Agency for Research on Cancer.