Christopher Love

12.091 Medical Geology/Geochemistry: Element Report IAP 2006, 01/30/2006 Christopher Love Introduction If you have ever looked carefully at your commercial container of salt sitting in the cupboard, then you have noticed that it is iodized. Have you ever wondered what that means, or why it is mentioned? The simple answer to these questions is that a form of the element, iodine, is added to the salt in order to keep you healthy. More complex is the underlying reason behind many different types of food fortifications: medical geology. According to medical geology, humans are linked with the natural processes of the Earth by requiring certain levels of particular elements and compounds to maintain optimal health. Thus, iodine is added to salt in order to supply enough iodine in your diet and satisfy the link between iodine and optimal health. In order to understand why iodine is important for humans to consume, I will examine iodine’s chemical properties, where it occurs naturally, how it interacts in biological processes, its geologic properties, and the implications of this multidisciplinary analysis. Chemical characteristics Chemistry identifies iodine according to its chemical properties, such as the ability to react with other substances, physical properties at various temperatures, and color. Iodine--chemical symbol ‘I’---is the name given to element 53 on the periodic table of elements. It is a nonmetallic element that belongs to Group 17/VIIA of the periodic table (the halogen group). The color of iodine in its gaseous state is violet, which gives iodine its name: it comes from the Greek word for violet (‘iodes’) [Atkins and Jones pp 592]. Iodine has many other known