Environment Impact and Health Effects of Beryllium
Beryllium is a steel gray, strong, and light-weight element that is toxic and primarily used as hardening agent in alloys. In group 2 (or IIA) of the periodic table, beryllium ranks about 51st in natural abundance among the elements in Earth’s crust. It has a high strength per unit weight. It is one of the light metals that have the highest melting points. Besides having excellent thermal conductivity and being nonmagnetic, beryllium resists attack by concentrated nitric acid and at standard temperature and pressures it resist oxidation when exposed to air. Beryllium was so named for its chief mineral that is an aluminum beryllium silicate. It was discovered as an oxide, now known as beryllia, in 1797 by French chemist Louis Nicolas Vauquelin. Because its soluble compounds are sweet-tasting, the new element was first called glucinium.
Beryllium tarnishes only slightly in air, becoming covered with a thin layer of oxide. The ability of beryllium to scratch glass is usually ascribed to this oxide coating. Beryllium compounds are generally white (or colorless in solution) and show great similarity in chemical properties to the corresponding compounds of aluminum. This similarity makes it difficult to separate beryllium from the aluminum that is almost always present in beryllium ores.
The most important industrial application of beryllium is in the manufacture of alloys. In very small amounts, the element adds strength, durability, and temperature stability to alloys. Copper-beryllium alloys make good hand tools in industries that use flammable solvents because the tools do not cause sparks when struck against other objects. Nickel-beryllium alloys are used for specialized electrical connections and various high temperature applications. The addition of beryllium to some metals often results in products that have high heat resistance, improved corrosion resistance, greater hardness, greater insulating properties, and better casting qualities. Many parts of supersonic aircraft are made of beryllium alloys because of their lightness, stiffness, and dimensional stability. Other applications make use of the nonmagnetic and nonsparking qualities of beryllium and the ability of the metal to conduct electricity. Beryllium has important use in many systems. In miniature, high-purity components made with beryllium, a single wire can carry hundreds of electronic signals. A typical application of beryllium-copper alloys is in the defense and aerospace industries.
Because X- rays easily pass through pure beryllium, the element is used as window material for X-ray tubes. Beryllium and its oxide, beryllia, are also used as a moderator, or so-called blanket, around the core of a nuclear reactor because of the tendency of beryllium to slow down or capture neutrons. Although beryllium products are safe to use and handle, the fumes and dust released during fabrication are highly toxic. Extreme care must be taken to avoid breathing or ingesting even very small amounts. Specially designed exhaust hoods are used by persons working with beryllium oxide. Beryllium and its oxide are being utilized more and more in industry. Besides its importance in aircraft and X-ray tubes, beryllium is used in computers, lasers, televisions, oceanographic instruments, and personal body armor.
The beryllium content on Earth crust and in soil is 2.6 ppm, and 6 ppm respectively. Beryllium in soil can pass into the plants grown on it, provided it in a soluble form. Typical levels in plants vary between 1 and 40 ppb that is too low to affect animals which eat these plants. Beryllium is found in 30 different minerals, the most important of which are bertrandite, beryl, chrysoberyl, and phenacite. Precious forms of beryl are aquamarine and emerald. Beryllium enters the air, water and soil as a result of natural processes and human activities. Whereas it occurs naturally in the environment in small amounts, humans add beryllium through production of metal and combustion of coal and oil. Beryllium exists in air as very small dust particles. It enters waterways during weathering of soils and rocks. Industrial emissions add beryllium to air and wastewater disposals. It usually settles in sediment. Beryllium as a chemical element occurs naturally in soils in small amounts, but human activities have also increased these beryllium levels. Beryllium is not likely to move deeper into the soil and dissolve within groundwater.
In water, chemicals will react with beryllium, to make it insoluble which is a good thing as the water-insoluble form of beryllium can cause much less harm to organisms than the water-soluble form. While beryllium has not been found to accumulate in the bodies of fish, some fruits and vegetables such as kidney beans and pears may contain significant levels of beryllium. Beryllium of these levels can enter animals that eat them, but luckily most animals excrete beryllium quickly through urine and feces. The uptake of beryllium has awful consequences mainly for human health. Nevertheless, laboratory tests have indicated that it is possible for beryllium to cause cancer and changes of DNA with animals. However, so far there is no field evidence to support these findings.
Though beryllium is one of the most toxic chemicals we know, it is not an element that is crucial for humans. This metallic element can be very harmful to humans when they breathe it in, because it can damage the lungs and cause pneumonia. The most commonly known effect of beryllium is called berylliosis, a dangerous and persistent lung disorder that can also damage other vital organs. In about 20% of all cases people die of this disease. It is the breathing in of beryllium in the workplace that causes berylliosis. People who have weakened immune systems are most susceptible to this disease. Beryllium can also cause allergic reactions to people who are hypersensitive to this chemical element and its compounds. These allergic reactions can be very dangerous and they can even cause a person to be seriously ill, a condition known as Chronic Beryllium Disease (CBD). The symptoms of this problem are: weakness, tiredness and breathing problems. Some people who suffer from CBD will develop anorexia and blueness of hands and feet. Sometimes people can even be in such a serious condition that CBD can cause them to tend towards premature death. Next to causing berylliosis and CBD, beryllium can also increase the chances of cancer development and DNA damage.