Plants, terrestrial molybdenum

Molybdenum occurs as iron molybdates in nature. Exposure occurs via weathering and release into rivers, from mining, and by the combustion of oil and coal. Terrestrial plants can contain enough Mo to be toxic to animals but the plants can still grow normally. Adding lime to soil increases Mo availability. 

The element molybdenum (Mo) is found in all living organisms and is considered to be an essential or beneficial micronutrient. However, molybdenum poisoning of ruminants has been reported in at least 15 states and 8 foreign countries. Molybdenum is used primarily in the manufacture of steel alloys. Its residues tend to be elevated in plants and soils near molybdenum mining and reclamation sites, fossil-fuel power plants, and molybdenum disposal areas. Concentrations of molybdenum are usually lower in fish and wildlife than in terrestrial macrophytes. 

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