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Beryllium poisoning is illness resulting from the toxic effect of beryllium in its elemental form or in various chemical compounds. The toxicity of beryllium depends upon the duration, intensity and frequency of exposure (features of dose), as well as the form of beryllium and the route of exposure (i.e. inhalation, dermal, ingestion). According to the International Agency for Research on Cancer (IARC), beryllium and beryllium compounds are Category 1 carcinogens; they are carcinogenic to both animals and humans. Since its discovery in the 1920s, Beryllium has been used in electronics, ceramics, research and development labs, aircraft, and the atomic energy and defense industry. In the 1940s the United States first recorded respiratory and dermal reactions among residents of communities surrounding beryllium manufacturing facilities and workers within them. At that time most construction trades and industries were unaware of the potential risks associated with beryllium exposure. Chronic berylliosis is a pulmonary and systemic granulomatous disease caused by exposure to beryllium. Acute beryllium disease in the form of chemical pneumonitis was first reported in Europe in 1933 and in the United States in 1943. Cases of chronic berylliosis were first described in 1946 among workers in plants manufacturing fluorescent lamps in Salem, Massachusetts. Chronic berylliosis resembles sarcoidosis in many respects, and the differential diagnosis is often difficult. It occasionally killed early workers in nuclear weapons design, such as Herbert L. Anderson. Although the use of beryllium compounds in fluorescent lighting tubes was discontinued in 1949, potential for exposure to beryllium exists in the nuclear weapons production and aerospace industries and in the refining of beryllium metal and melting of beryllium-containing alloys, the manufacturing of electronic devices, and the handling of other beryllium-containing material. Early researchers tasted beryllium and its various compounds for sweetness in order to verify its presence. Modern diagnostic equipment no longer necessitates this highly risky procedure. Beryllium and its compounds should be handled with great care and special precautions must be taken when carrying out any activity which could result in the release of beryllium dust (lung cancer is a possible result of prolonged exposure to beryllium laden dust). Beryllium in air and on surfaces can be detected using dilute ammonium bifluoride for dissolution and fluorescence detection with beryllium bound to sulfonated hydroxybenzoquinoline, allowing detection up to 100 times lower than the recommended limit for beryllium concentration in the workplace. ==Inhalation== Beryllium is harmful if inhaled and the effects depend on the duration, intensity, and frequency of exposure. When inhaled, beryllium becomes deposited into the lungs, from which the body has difficulty expelling it. If beryllium concentrations in air are high enough (greater than ), an acute condition can result, called acute beryllium disease, which resembles pneumonia. Occupational and community air standards are effective in preventing most acute lung damage. Long-term beryllium exposure can increase the risk of developing lung cancer. The more common serious health problem from beryllium today is chronic beryllium disease (CBD). It continues to occur in industries as diverse as metal recycling, dental laboratories, alloy manufacturing, nuclear weapons production and metal machine shops that work with alloys containing small amounts of beryllium. CBD can occur even when levels of beryllium are lower than the legal limits for workers. A 2008 report from the United States National Research Council said that worker exposure to beryllium should be kept "at the lowest feasible level," as the agency's research could not establish any safe level of exposure. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Beryllium poisoning」の詳細全文を読む スポンサード リンク
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