Explore the multifaceted element Selenium on this episode of 3B's World Podcast. Host Boni traces its 1817 discovery during industrial analysis and its evocative name linked to the Moon. Delve into the unique chemical and physical properties of this metalloid, including its notable photoconductivity. Learn about its distribution in the Earth's crust, its variable concentration in soils, and its presence in the food chain – from Brazil nuts to seafood. Critically, we examine Selenium's role as an essential trace mineral in human health, discussing its function in vital selenoproteins involved in antioxidant defense, thyroid hormone metabolism, and immune response. Understand the health implications of both selenium deficiency and toxicity. Join Boni for an informative exploration of Selenium.