Selenium Information

Selenium is a non-metal and is chemically related to sulfur and tellurium and it is a by- product of sulfuric acid production. It is represented by the chemical symbol Se. Its Greek meaning is "Moon" due to its purplish-grey color. It was discovered by Jon Jokobs Berzelius in 1817 and later noticed around 1954 medically because of its toxicity to humans that were working in the industry.

Selenium is usually found in plant foods that are grown in soil that have a high selenium content. Nebraska and the Dakotas have very high levels of selenium versus China and Russia which have extremely low levels. Of course selenium can be found in meats and seafood because the animals eat the grains and plants that are grown in these soils and the selenium is stored in the animal's muscles. The Brazil nut has high level of selenium. It contains as much as 544 micrograms per ounce. Other foods such as mushrooms, tuna, beef and cod are good sources of selenium.

Selenium is very toxic in large doses and exceeding the Tolerable Upper Intake Level which is 400 micrograms per day (for adults) can be fatal. The Tolerable Upper Intake Lever was discovered by a study done on five Chinese patients in 1986 that had eaten corn grown in extremely selenium rich stony coal. Exceeding this level can lead to selenosis. Selenosis is seen a lot in live stock because of them ingesting selenium found in plants grown in the areas where they are grazing. Selenosis symptoms are gastrointestinal disorders, sloughing or white blotchy nails, garlic odor on the breath, fatigue, irritability and neurological damage. Extreme cases can result in cirrhosis of the liver, pulmonary edema and death.

Although Selenium is toxic in large doses, it is an essential micronutrient. It is used in vitamin preparation in dose sizes of 50-200 micrograms for adults. It functions as a cofactor for reduction of antioxidant enzymes. Selenium plays a role in the functioning of the thyroid gland and in every cell that uses thyroid hormones. The human body is believed to have a level range of 13-20 milligrams. However, selenium deficiency can occur. It occurs normally in individuals with severe intestinal issues such as Crohn's disease or advanced aged people (over 90 years old). Specific diseases such as Keshan disease, Kashin-Beck disease and Myxedematous Endemic Cretinism. Selenium levels may be measured in blood, plasma, serum and urine.

Current health issues surrounding selenium are studies on cancer, heart disease, arthritis, HIV/AIDs, Tuberculosis, and diabetes and how the use of selenium in your dietary intake can help with these diseases and disorders.

Selenium serves other non-medical purposes such as chemistry because it is a catalyst in chemical reactions. It is used in photography as toner and they are used in x-ray sheets but the largest use is in the manufacturing of glass and ceramics. It helps give glass its red color.