CAS No. 7440-41-7
Pure beryllium is a hard gray metal, the lightest of all metals, and can be found in mineral rocks, coal, soil, and volcanic dust. Beryllium compounds are commercially mined, and refined beryllium is used in mirrors and special metal alloys for the automobile, computer, nuclear, electrical, aircraft, and machine-parts industries. Beryllium is also used in the production of sports equipment such as golf clubs and bike frames. In medicine, beryllium is used in instruments, x-ray machines, and dental bridges. Burning coal and oil can produce small amounts of beryllium dust that can be released into the air.
Exposure to beryllium occurs mostly in the workplace, near some hazardous waste sites, and from breathing tobacco smoke. Two types of minerals, bertrandite and beryl, are mined for commercial recovery of beryllium. Low-level beryllium exposure in the general population can occur through breathing air, eating food, or drinking water containing the metal. In studies of laboratory animals, inhaled insoluble beryllium sulfate was retained in the lungs and nearby lymph nodes; less than one percent of the inhaled dose was slowly absorbed into the blood and eventually incorporated into the skeleton. A half-life of 450 days has been calculated for beryllium elimination from the human skeleton (IPCS, 1990).
Human health effects from beryllium at low environmental doses or at biomonitored levels from low environmental exposures are unknown. The effects of occupational exposure to beryllium depend on the concentration of beryllium in the inhaled air and the duration of air exposure. Air levels greater than 100 µg/m3 can result in erythema and edema of the lung mucosa, which produces pneumonitis. Chronic beryllium disease, or berylliosis, is a granulomatous interstitial lung disease that is caused by chronic beryllium inhalation and the resultant immunologic response. Genetic factors modify individual sensitivity to beryllium and susceptibility to developing chronic beryllium disease (McCanlies et al., 2003; Maier 2002). Skin exposure can result in delayed hypersensitivity reactions, including contact dermatitis and subcutaneous nodules.
Workplace air standards and guidelines for external exposure have been established by OSHA and ACGIH, respectively; and drinking water and environmental standards have been established by U. S. EPA. IARC has classified beryllium as a human carcinogen, based upon excess lung and central nervous system cancers in studies of workers. NTP considers beryllium to be a known human carcinogen. More information about external exposure (i.e., environmental levels) and health effects is available from ATSDR at http://www.atsdr.cdc.gov/toxprofiles/index.asp.
Urinary beryllium levels represent recent and accumulated exposure. Levels of beryllium in urine for the U.S. population were generally undetectable in NHANES 1999-2000, 2001-2002, and 2003-2004. In other studies, urinary levels for general populations have been either undetectable or had different detection limits than in the National Report on Human Exposure to Environmental Chemicals (CDC, 2012; Komaromy-Hiller et al., 2000; Minoia et al., 1990; Paschal et al., 1998). Hamilton et al. (1994) noted that analytical methods used in several general population studies appeared to have limits of detection that were insufficiently low (i.e., less than 0.1 µg/L). Apostoli and Schaller (2001) stated that detection limits in earlier studies were inadequate to estimate non-occupational exposures. They reported urinary beryllium levels ranging from 0.12 to 0.15 µg/L in workers exposed at the recommended threshold limit value (Apostoli and Schaller, 2001). Given these results, which are close to the limit of detection, 0.13 µg/L, and the 95th percentile for males in NHANES 2001-2002, and the fact that most NHANES participant levels were undetectable, it is possible that urinary beryllium levels in the U.S. population are lower than levels considered safe for workers. In more recent NHANES 2005-2010 survey periods, the limit of detection decreased to 0.072 µg/L, and most participant levels still were undetectable (CDC, 2012).
Finding a measurable amount of beryllium in urine does not imply that the level of beryllium causes an adverse health effect. Biomonitoring studies on levels of beryllium provide physicians and public health officials with reference values so that they can determine whether people have been exposed to higher levels of beryllium than are found in the general population. Biomonitoring data can also help scientists plan and conduct research on exposure and health effects.
Apostoli P, Schaller KH. Urinary beryllium--a suitable tool for assessing occupational and environmental beryllium exposure. Int Arch Occup Environ Health 2001;74:162-166.
Centers for Disease Control and Prevention (CDC). Fourth National Report on Human Exposure to Environmental Chemicals. Updated Tables, 2012. [online] Available at URL: http://www.cdc.gov/exposurereport/. 10/16/12
Hamilton EI, Sabbioni E, Van der Venne MT. Element reference values in tissues from inhabitants of the European community. VI. Review of elements in blood, plasma and urine and a critical evaluation of reference values for the United Kingdom population. Sci Total Environ 1994;158:165-190.
International Programme on Chemical Safety (IPCS). Environmental Health Criteria. 106. Beryllium [online]. 1990. Available at URL: http://www.inchem.org/documents/ehc/ehc/ehc106.htm. 3/27/08
Komaromy-Hiller G, Ash KO, Costa R, Howerton K. Comparison of representative ranges based on U.S. patient population and literature reference intervals for urinary trace elements. Clin Chim Acta 2000;296(1-2):71-90.
Maier L. Genetic and exposure risks for chronic beryllium disease. Clin Chest Med 2002;23:827-839.
McCanlies EC, Kriess K, Andrew M, Weston A. HLA-DPB1 and chronic beryllium disease: a HuGE review. Am J Epidemiol 2003:157:388-398.
Minoia C, Sabbioni E, Apostoli P, Pietra R, Pozzoli L, Gallorini M, et al. Trace element reference values in tissues from inhabitants of the European community I. A study of 46 elements in urine, blood, and serum of Italian subjects. Sci Total Environ 1990;95:89-105.
Paschal DC, Ting BG, Morrow JC, Pirkle JL, Jackson RJ, Sampson EJ, et al. Trace metals in urine of United States residents: reference range concentrations. Environ Res 1998;76(1):53-59.