Chromium is the 21st most abundant element in the Earth’s crust and can be present in different chemical forms in plants, soil and volcanic dust, water, humans and animals. Because it is a prevalent natural element, chromium can be present in the air, food, and water.
Chromium can change from one form to another in water and soil. Hexavalent Chromium is one of these chemical forms. Hexavalent chromium is also commonly called chromium 6, chromium VI, chrome 6, Cr(VI), Cr+6 or hex chrome. Other common forms of chromium are trivalent chromium, also known as chromium 3, and the metal form, chromium 0. Chromium can convert between chromium 3 and chromium 6 in different environments.