Existence of human civilization is closely connected with this, indeed, magic microelement. The properties of iodine were well-known for people before the discovery of this element. It has been in a human, in the environment for thousands of years. People had learnt how to use wonder-working power of an unknown microelement.

Only in 1811, iodine was officially discovered by French chemist Bernard Courtois. The famous scientist Joseph Louis Gay-Lussac gave a name to iodine.

Iodine belongs to the number of elements in which overwhelming majority of atoms is in the state of so called dispersion. All forms of existence of iodine, all its transformations are defined, in the main, by influence of water. Gigantic mass of iodine on our planet is situated in waters of ocean.

That fact that iodine is closely connected with water in natural conditions was a happy circumstance which gave opportunity to find the forms of existence in our nature, to solve a mystery of enigmatic state of dispersion of iodine. An important mystery of this element is a mystery of its unique antiseptic action.

A wonderful expression of the great biologist Emil Du Bois-Reymond sounded in the lecture “Seven world mysteries” which was read on the open conference on the Academy of Science during the celebration of Leibniz anniversary on 8th July, 1880: “A living organism is animated water.”

A living cell is a distinctive microbiohydrosphere as 60—99.7% of it consists of water. Namely because of this history of iodine in biosphere is full of living, unusually various and fascinating transformations of this element full of mysteries.

Water-plant and bacterial associations presented the main component of biosphere about 3 milliard years ago and at those times water-plants had already had an ability to concentrate iodine.

Molecular iodine, interacting with water, as it generally known gives iodic acid HIO, where iodine is in a positively univalent form-the only form in which iodine displays its various biological activity. Comprehensive researches were conducted by outstanding scientist V.O. Mohnach.

Sea sponges which belong to families Aplysinidae, Euspongiae, Hippospongiae and others are exceptionally rich on iodine. It is said in some researches that organic substance of sponges contains 3, 5- di-iodotyrosine. What role can play this iodine amino acid in metabolic processes which as it generally known is not active in higher mammals but it serves for creation of thyroxine?

It is, indeed, a miracle that in milliards of years of phylogenesis iodine amino acid in organisms which reached the superior development stage began to play the role of intermediate link in the processes of creation of important hormones – thyroxine and three-iodine.