As opposed to inland waters that occupy only 0,2/10 of surface of our planet, seas and oceans occupy about 7/10 of the surface. They form an independent whole whose configuration highly varied throughout time.

The most characteristic feature of the sea water is its saltness. 

The sea water is a salt and gases of very different chemical nature solution. The sea waters far from shores, with a very stable composition, are very different form the ones harvested near the shores or from inland waters.

The interesting chemical features are given not by the absolute values of the concentrations, but by the ratio between the relative content of the main components. The ratio between their concentrations is somewhat similar in marine waters and this determines a certain constant in the oceanic environment composition.

The main component of salinity is sodium chloride, with 80% of the total, which is accompanied by other elements in easily dosed percentages.

Among these are the magnesium chloride, magnesium, calcium and potassium sulfates, calcium carbonate, magnesium bromide.

If Na, Mg, Ca, K and Br are, together with chlorine, sulphates, bicarbonates, strontium and baric acid (710 mg-l) the main components of sea waters, these waters also contain other elements in extremely low concentrations, often only as trace elements. They represent minor components or trace elements of sea waters: I, F, Ag, Au, Si, nitrates, phosphates and so on. They can be determined with difficulty, by means of special analysis but, under a biological aspect they are very important because they can extract and retain in their body some organisms from the water.

The sea water contains trace elements, that are essential elements that the human body cannot synthesize. In extremely low quantities, they are beneficial for the good functioning of the body.

The role of trace elements:

They strengthen the immune system and catalyze the ionization phenomena.

The copper has a anti infectious, anti viral, anti-inflammatory role and strengthens the defence mechanisms.

The magnesium intervenes in the immunological mechanisms and antialergic reactions.

The iron improves cellular oxygenation and insures a good functioning of the respiratory apparatus.

The sulphate adjusts the pulmonary ventilation and protects against respiratory infections.

The selenium has antioxidant and anti-inflammatory properties and maintains the integrity of the cellular membrane.