Iodine

The name iodine comes from the Greek word 'iodes', which means 'violet'. This at first would make no sense, as solid iodine is a blue-black non-metal that is very shiny. However, at normal temperatures, iodine turns into its gaseous form, and the gas is a violet color. Iodine is only found in solid and gas forms, there is no liquid state.


I called iodine a 'non-metal' above- it is actually halogen. Halogen is a non-metal. However, iodine also possesses a lot of metallic qualities.


The thyroid gland uses iodine to make the hormones thyroxine and triiodothyronine. Insufficient iodine leads to development of a goiter, which is a swelling of the thyroid gland. Iodine deficiency is believed to be the leading preventable cause of mental retardation. Excessive iodine symptoms are similar to those of iodine insufficiency. Iodine toxicity is more severe if a person has a selenium deficiency. Iodine is used extensively in medicine. However, some people develop a chemical sensitivity to iodine. Sensitive individuals may develop a rash when swabbed with tincture of iodine. In rare cases, anaphylactic shock has resulted from medical exposure to iodine.