The heavy metal Chromium has several oxidation states but it occurs predominantly in two forms: trivalent (Cr3+) and hexavalent (Cr6+) states. Unlike trivalent chromium, the hexavalent form rarely exists naturally being originated by anthropogenic sources. Hexavalent chromium (Cr (VI)) is very often an issue in ecotoxicity studies for two main reasons: (i) due to its importance as a pollutant that threats especially aquatic ecosystems and (ii) due to its value as a reference toxicant in standard toxicity tests. Cr (VI) is used in industry (wood preservation, leather tanning, metal finishing,...