Fertilizers play an essential role in maintaining and/or increasing world food production. In many parts of the world spectacular crop yield increases have been recorded following fertilizer application. Additionally, inorganic fertilizers have become an integral part of sustainable farming systems, by allowing farmers to supply specific nutrients to crops that are required for optimum and long-term crop or pasture production.
Some inorganic fertilizers are known to contain contaminant metals, metalloids and radionuclides. Concentrations of contaminants in fertilizers are either derived from the source materials from which fertilizers are manufactured or are introduced into the fertilizer during the manufacturing process. The latter is very uncommon and the dominant source of contaminants in manufactured fertilizers is the raw material used for manufacturing. Pure nitrogenous and potassic fertilizers generally contain few trace elemental contaminants (for a review see [1]) so these will not be considered further in this chapter. The dominant sources of fertilizer contaminants are the raw materials used to manufacture phosphatic and micronutrient fertilizers [2].