Dr. Arthur Kilness of Rapid City, South Dakota devoted more than thirty-five years of his career to the study of selenium. He was particularly interested in selenium because of the high concentrations which are often found in the alkaline soils in South Dakota.
Selenium is a naturally occurring chemical element, usually found in rocks. Its original source was probably volcanic activity. It enters the soil and water through weathering of selenium-rich rocks.
Microscopic levels of selenium found in nuts, grains and grasses help keep humans and animals healthy. But what happens when too much selenium is consumed?
Kilness knew that plants grown in selenium-rich soils posed a threat to wildlife and domestic livestock. High doses of selenium are five times more poisonous that arsenic. Kilness cautioned hunters and fishermen. Fish living in water with high concentrations of selenium pose a danger to the anglers who catch and eat them. Similarly, ducks and geese can accumulate unhealthy levels of selenium in their flesh, making them unfit for human consumption.
See the Arthur W. Kilness papers at UW’s American Heritage Center to learn more.