Simultaneous determination of 15 inorganic elements in export vegetables by microwave digestion-inductively coupled plasma mass spectrometry method

An analytical method based on inductively coupled plasma mass spectrometry( ICP-MS) was developed for the simultaneous determination of 15 inorganic elements( Mg,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Se,Cd,Tb,Hg and Pb) in export vegetables. After the samples were pretreated by microwave digestion under HNO3-H2O2,octopole collision-reaction system( ORS) was used to eliminate the polyatomic interferences.Sc,Rh,In and Ir were used as internal standard elements to compensate matrix effect and signal drift. The results indicated that the concentrations and responses of each element showed a good linear relationship in the range of 0~50 mg·kg-1with correlation coefficients higher than 0.9995. The limits of detection( LOD) were in the range of 0.003 ~ 37.21 μg·kg-1.The established method was validated by analyzing the National Standard Reference Material of Beans( GBW10021),Celery( GBW10048) and Green Chinese Onion( GBW10049).The relative standard deviation values of reproducibility( n = 6) were 1.4% ~19.4%,and the analysis results were all in material reference range.Among the15 elements,As,Cd,Pb,Cr and Hg were lower than relevant limit requirements. Furthermore,the elements content level of export-vegetables from Lianyungang was basically established,which could provide theoretical basis for the cultivation and export of vegetables.