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Chromium (Cr) belongs to 3D block elements and it exists in three valence states as metallic state Cr(0), Cr(III), and Cr(VI). Cr(III) is insoluble in water; it only forms hydroxide and oxy‐hydroxide and solid solution with iron (Fe), while Cr(VI) is resolvable in water under environmental conditions. Cr occurs in the form of chromate (CrO₄²⁻) and dichromate ions (Cr₂O₇²⁻). Cr(VI) is more lethal than Cr(III). Chromium pollution in water is accumulated by natural sources as well as anthropogenic sources. However, industrial sources as chrome plating, steel production, corrosion inhibition, wood preservative, well drilling, and paint and primer pigments lead to chromium contamination in water. Nevertheless, natural sources like rock ores also lead to chromium contamination in groundwater (Zhitkovich 2011).