The name beryllium comes from the Greek word 'beryllos' that describes the industrially important stone beryl. Emerald is a precious form of beryllium mineral containing traces of chromium that add a green hue to the stone. Alloys of beryllium with copper and nickel have excellent electrical and thermal conductivities. For this reason, these alloys are used for fabricating aircrafts, missiles, spacecraft and communication satellites. (reference)
When inhaled as a particulate, some beryllium compounds can lead to an irreversible and sometimes fatal scarring of the lungs known as berylliosis or chronic beryllium disease (CBD). It is probably an allergic reaction, in which 2-5% of people exposed are more susceptible than others; but sensitivity can increase with exposure. There is currently no widely available test to find out who is sensitive to beryllium before exposure occurs. Even small amounts of beryllium particles of respirable size may trigger sensitivity, and CBD can take from a few months to 30 years to develop (average latency period of 10 to 15 years), even for those with only minor incidental exposure to beryllium dust. Not all forms of beryllium are equally toxic.
Primarily a lung disease, CBD may also affect other organs, such as the lymph nodes, skin, spleen, liver, kidneys, and heart. Short-term beryllium exposure may lead to inflammation, reddening or swelling of the lungs, a condition known as Acute Beryllium Disease. If beryllium enters cuts in the skin, non-cancerous ulcerating growths may form. Symptoms of CBD may include the following:
CBD is treatable, but not curable. Treatment may involve use of steroids to reduce inflammation, which may slow the progress of CBD by reducing the buildup of scar tissue and delaying permanent lung damage. Some do not respond well to treatment, and others cannot tolerate the side effects of long-term steroid treatment, including slower healing of infections, calcium loss from the bones, higher blood cholesterol, and fluid and salt retention which may aggravate heart or kidney disease.
Beryllium is regulated by OSHA and by EPA, under the Clean Air Act National Emission Standards for Hazardous Air Pollutants program (Section 112). Beryllium and its compounds are listed as toxic chemicals under the Emergency Planning and Community Right-to-Know Act of 1986; estimates of releases of beryllium and its compounds into air, water or land must be reported annually and entered into the national Toxic Release Inventory (TRI). The U.S. Department of Energy proposed standards in December 1998 to establish a chronic beryllium disease prevention program that would reduce worker exposure.
The Department of Health and Human Services (DHHS) and the International Agency for Research on Cancer (IARC) have determined that beryllium is a human carcinogen. The EPA has determined that beryllium is a probable human carcinogen. EPA has estimated that lifetime exposure to 0.04 microgram/m3 of airborne beryllium can result in a one in a thousand chance of developing cancer. The EPA limit for beryllium that industries may release into the air is 0.01 micrograms/m3, averaged over a 30-day period. OSHA's limit is 2 micrograms/m3 in workroom air for an 8-hour work shift. EPA's limit for drinking water is 0.004 mg/l.
Ingestion of beryllium is thought to present a low risk of toxicity, because it is not very easily absorbed by the stomach and intestines. However, dogs fed a diet containing beryllium developed ulcers. It is still not recommended to taste beryllium or its compounds. Ambient air levels of beryllium are normally very low, from 0.00003-0.0002 micrograms/m3.
Abraded or lacerated skin, exposed to beryllium may develop rashes or ulcers. Small amounts of beryllium occur in some rocks and fossil fuels. Consequently, exposure to low concentrations is almost inevitable. It is released by the burning of coal or petroleum. It also erodes from rocks and soils, but once it enters the aqueous environment, most of it sticks to clay particles and settles out into the sediment. Once bound to soil particles, beryllium will remain relatively insoluble due to the insolubility of the oxides and hydroxides at normal pH. It does not accumulate in the food chain.