Analyses and Assessment of Heavy Metal Pollution of Vegetables in Xi'an

Heavy metal elements Hg,As,Pb,Cr and Cd in 40 samples from 10 kinds of vegetables in Xi'an were determined by AAS and AFS.The heavy metal pollution was assessed with the national food hygiene standard(GB18406.1-2001).The results indicated that 83 percent of the samples tested were qualified in heavy metal contents.Pb was the main pollution element which existed in the 10 kinds of vegetables among the 40 samples tested,77.5 percent of the samples contain over-limited Pb.Pb content was higher in leaf vegetables than that in eggplant and fruit vegetables;Hg and Cr pollution appeared partly in vegetables,exceeding-standard ratios of them were 10% and 2.5%,respectively.While As and Cd did not exceeded national standard level,and qualification rates of them were 100%.The intensity of Pb pollution in different vegetables was as follows:lettucegarden chrysanthemumleekeggplantcelerycowpeagreen pepperleaf-used lettucetomatocucumber,and the intensity of Pb pollution in vegetable-cultivating district in Xian suburb was :westernnortherneasternsouthern.