Hexavalent chromium (Cr+6), in contrast, is toxic. The chemical is used in a number of industrial processes as well as for leather tanning, chromium plating, ...HomeDemystifiedHealth&MedicineShare:FacebookTwitterHomeDemystifiedHealth&MedicineWhatisHexavalentChromium(orChromium-6)?Share:FacebookTwitterWRITTENBYJohnP.RaffertyJohnP.RaffertywritesaboutEarthprocessesandtheenvironment.HeservescurrentlyastheeditorofEarthandlifesciences,coveringclimatology,geology,zoology,andothertopicsthatrelateto...UniversalPicturesManypeopleknowhexavalentchromiumasasilentantagonistinthebiopicErinBrockovich(2000),whichstarredAmericanactressJuliaRobertsasalegalassistanttakingonacompanyaccusedofpollutingthewaterofruralHinkley,California,whichresultedinelevatedratesofcanceranddeathamongthetown’sresidents.Butwhatishexavalentchromium,andwhatisitusedfor?Industryaddschromium(Cr)toironandnickeltomakemetalalloysespeciallycharacterizedbytheirhighresistancetocorrosionandoxidation.Usedinsmallamounts,chromiumhardenssteel.Stainlesssteelsarealloysofchromiumandironinwhichthechromiumcontentvariesfrom10to26percent.Chromiumalloysareusedtomakeproductssuchasoiltubing,automobiletrim,andcutlery.Chromiteisusedasarefractory(asubstancethatisresistanttoheat)andasarawmaterialfortheproductionofchromiumchemicals.Themostcommonformsofchromiumare+2,+3,and+6oxidationstates.Inverysmallamounts,trivalentchromium(Cr+3)isusefulinanimalmetabolism,helpingtoregulateglucoselevelsandincreasetheeffectivenessofinsulininthebody. Thisformofchromiumappearsinanumberoffoods,includingbroccoli,potatoes,andgarlic.TheU.S.EnvironmentalProtectionAgency(EPA)notesthat,onaverage,peopletakeinlessthan0.2to0.4microgramfromtheair,lessthan2microgramsfromthewater,andlessthan60microgramsfromfoodeachday. Hexavalentchromium(Cr+6),incontrast,istoxic.Thechemicalisusedinanumberofindustrialprocessesaswellasforleathertanning,chromiumplating,coloredglassmakingandinpaintpigmentsandinksthatcolorplasticsandfabricsandserveascorrosion-resistantcoatings.Itishazardousw