Iodine: biological information
In nature, iodine exists as iodide ions, I-, and it is as iodide that it is taken into our bodies. Iodine is an essential component of the human diet and in fact appears to be the heaviest required element in the diet. Iodine compounds are useful in medicine.
Lack of iodine in the diet is a cause of goitre (Derbyshire neck). This condition is rare now as table salt is dosed with a little iodide.
Levels in humans
- Human abundance by weight: 200 ppb by weight
- Human abundance by atoms: 10 atoms relative to C = 1000000
How much iodine is in your body? Find out here.
You can use this form to calculate how much iodine your body contains. Enter your weight in either kilograms or pounds and click the "Calculate" button. You must enter a number, not text! Elements for which there are no data will always give a value of zero for the weight, no matter what you put in the weight box.
Hazards and Risks
Hazards and risks associated with iodine:
Elemental iodine, I2, is toxic, and its vapour irritates the eyes and lungs. The maximum allowable concentration in air when working with iodine is just 1 mg m-3. All iodides are toxic if taken in excess.
- J.E. Huheey, E.A. Keiter, and R.L. Keiter in Inorganic Chemistry : Principles of Structure and Reactivity, 4th edition, HarperCollins, New York, USA, 1993.
- S. Budavari (Ed.) in The Merck Index, 11th ed., Merck, USA, 1989.
- N.N. Greenwood and A. Earnshaw in Chemistry of the Elements, 2nd edition, Butterworth, UK, 1997.