Selenium, in the most common conditions, is a naturally occurring element that can be found in rocks, soil, as water Many believe that its source is from volcanic activity. Selenium found near soil in a toxic state can be absorbed by the soil and through water and wind erosion and sedimentation processes these particles are distributed and deposited into the soil. Therefore, the soil becomes intoxicated and the roots of the plants are destroyed, causing the plant to wither and eventually die if the process continuous.
Selenium deficiency can also be very dangerous. Humans are effected by Selenium poisoning by many symptoms. Of those symptoms, they include brittle nails, cirrhosis of the liver, anemia, loss of hair, and erosions of long bones.
In excessive selenium rates, there have been records of packs of animals being affected. By eating plants in their grazing fields, some animals were recorded to have had their hoofs fall off, a symptom that is now recognized as characteristic of chronic selenosis. Animals feeding on plants that store selenium develop conditions such as the blind staggers as well.
Blind Staggers syndrome may occur shortly after the animal has consumed very high amounts of Selenium for an elongated period. The symptoms include impaired vision, roaming in circles, and a smaller diet. Without getting the animal off the high Selenium diet, it can progress into variable amounts of paralysis and possibly death.
Another disease from Selenium poisoning in animals is Alkali Disease. This is a more chronic disorder with lower levels and longer span of taking in selenium. Symptoms include emaciation, loss of hair, deformation and shedding of hooves, loss of vitality, and erosion of the joints of long bones.