Iodine
From Chemistry
Iodine is a Chemical element with the atomic symbol I and Atomic number 53. Iodine was popularly used as a disinfectant for open cuts and used widely in medical practices. Iodine was and still is commonly used in dyes and photography. Iodine is also very soluble in water,and can be found concentrated in seawater. Iodine is the second least reactive of the halogens, and when freed from its compounds, iodine forms diatomic molecules (I2). Iodine has many isotopes that can be used to treat thyroid cancer, and some that cause it. In the event of a nuclear attack, it was speculated that heavy doses of iodine prevented and radioactive isotopes from entering your body and being absorbed by the thyroid, because the thyroid can only absorb so much iodine at one time. The most stable iodine isotope is 131I, or commonly known as radioiodine, or simply, Iodine-131.
