Abstract:
Vegetablesarevitaltohumandietprovidingessentialnutrientstomaintainnormal
physiologicalfunctions.Contaminationofagriculturalcropsincludingvegetablesbyheavy
metalsduetogeochemicalprocessesandvariousanthropogenicactivitiesarebecoming
priorityconcernworldwide.Thisstudyaimstoinvestigateconcentrationofselectedheavy
metalsincabbageandsupportingsoilsamplescollectedfrom potentiallyvegetableproducing
threevillagesofHidabuAbotedistrictofNorthShowa,Oromiaregionalstate,Ethiopia.Wetacid
digestiontechniquewasemployedtodigestthecabbageandsoilsamples.Thecabbage
samplewasdigestedusingmixtureofHNO3,HClO4andH2O2involumeratioof4:3:1,whilefor
soilsampledigestionmixtureofHF,HNO3,HClO4andHClwereusedinvolumeratioof5:5:3:5
followingstandardprotocols.FAASwasemployedforheavymetalsanalysis.Estimationof
qualitycontrolparameterswerealsocarriedouttovalidatetheusedanalyticalmethod.The
measuredvaluesofmethodvalidationparameterswererangedfrom 0.018–0.037mg/kg-dw,
0.9918–0.9996,81.4–116.1%and0.4977–12.49%,forLOQ,r2
,%recovery,and%RSD,
respectively.Ourresultshowedthatallthestudiedheavymetalswerefound/quantifiedinall
cabbageandsoilsamples.Themean(minimum –maximum)valuesofthestudiedheavy
metalsmeasuredwere0.74(0.11-2.22)mg/kg-dw,and0.846(0.176-2.22)mg/kg-dwin
cabbageandsupportingsoilsamples,respectively.Theconcentrationsofthemetalsin
cabbageareintheorderofCd<Pb<Zn<Cu<Ni<Co<Cr,butinsupportingsoilfollowedthe
orderofCd<Pb<Co<Cu<Ni<Zn<Cr.Thecomparisonofourresultswithinternationally
establishedstandardlimitsshowedthatCd,CrandPbconcentrationlevelsincabbage
exceededtheguidelinevalue,indicatingtheirpossiblehealthrisktotheconsumers
