ABSTRACT
Phosphorus is a ubiquitous element, being present in us and around us everywhere (Table 2.1). Phosphorus is not found free in nature and almost always occurs in the fully oxidised state as phosphate, at least on planet earth. The element is widely distributed in this form in soils, rocks, in the oceans, in all living cells, in most foods and in many man-made materials where nitrogen is also usually present. Unlike the latter, however, phosphorus is generally absent from the atmosphere.
