Molybdenum doesn't occur in nature in elementary conditions, it occurs as molybdenite and little commercial ores like wulfenite or like side product in copper and wolfram mining. It is using in nuclear energy, in military purposes, electrical produces, naphtha industry, industry of glass, ceramics, pigments, for production of special steals, wolfram, etc. Molybdenum compounds are using as additions of greases and in agriculture like prevention of molybdenum deficit at crops.
Origin in water
Molybdenum often occurs in waters because of molybdenum good solubility, especially when molybdenum makes complex anion with oxygen, as in neutral also in acid environment. In specific studies, it is settled inverse dependence of molybdenum concentration with calcium- hydrocarbonate content in water. The highest concentration of molybdenum is in sedimentary rocks, especially in clays, clayey schist, but the smallest content is in sandstone and sandy rocks. In igneous rocks the highest concentration is in acid and base rocks.
Molybdenum is essential element. There are not bioaccumulation in human tissues and animal tissues. It absorbs in gastrointestinal channel and concentrates in liver, kidneys and bones. The main elimination is through urinary channel.
It helps in metabolism of carbon-hydrates and lipids. It is vital part of enzymes which is responsible for iron operation. It helps in anaemia prevention. Molybdenum betters general conditions of organism.
Under the acute toxication of molybdenum are liver, kidneys, sometimes adrenal glands and spleen.
Maximal allowable concentrations
According to recommendations of our rules for drinking water (Sl. list SRJ 42/98) limitary value for molybdenum is 70 mg/1.