The ion IO3-, known as iodate, is a polyatomic ion composed of one iodine atom and three oxygen atoms. It carries a negative charge of -1. Iodate is commonly found in various chemical compounds and is used in analytical chemistry and as a source of iodine in some applications. Iodate can be formed through the oxidation of iodine in the presence of oxygen. It is often used in the food industry as a food additive and in water treatment processes. Additionally, iodate plays a role in the iodine cycle, which is essential for maintaining proper thyroid function in living organisms.