The Right Dose: Dose Response Theory

Selenium: Hazards

A deficiency of selenium has been linked to leukemia, rheumatoid arthritis, and fibrocystic breast disease. Overdose may bring the loss of teeth and hair, painful swelling of fingers, fatigue, nausea, and vomiting. In livestock one finds "staggering", cracking & loss of hooves, and loss of tails.

"Locoweed" (genus Astragalus), which concentrates selenium, is lethal to horses and other livestock.