Chromium is one of the most widely distributed heavy metals in the earth’s crust. It is normally found in two oxidation states ie Cr(III) and Cr(VI). Chromium is required
in small quantities as an essential trace metal, nutrient and its deficiency may result in several physiological disorders.
Most of the biological tissues contain Cr(III) which is usually nontoxic, where as Cr(VI) is a highly toxic form of the metal to the organisms. It is known that an increase in
the content of this element in soils makes them infertile and that the toxic effect depends to some extent on the oxidation state of chromium. On the other hand, the introduction of chromium salts into soils have some positive effects due to activation of some biochemical processes