西安市蔬菜中重金属污染分析评价

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

采用原子吸收光谱法和原子荧光光度法,测定了西安市郊区10种蔬菜40个样品中汞、砷、铅、铬和镉的含量;并以国家标准(GB18406.1-2001)为依据,对蔬菜重金属污染状况进行分析评价,以明确西安市蔬菜中重金属污染状况.结果表明,西安市10种蔬菜总体合格率为83%,铅是蔬菜中的主要污染元素,在测定的10种蔬菜中普遍存在,总体超标率为77.5%;汞和铬只在芹菜和茼蒿上出现污染,总体超标率分别为10%和2.5%;叶菜类蔬菜铅污染>茄果类蔬菜;砷和镉含量均未超过国家标准规定,合格率为100%.铅的污染程度按蔬菜种类依次为:生菜>茼蒿>韭菜>茄子>芹菜>豇豆>青椒>油麦菜>西红柿>黄瓜,按不同生产区域依次为:西郊>北郊>东郊>南郊.

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：lettuce2〉garden ebrysantbemum〉leek〉eggplant〉celery〉cowpea〉green pepper〉leaf-used lettuce〉tomato〉cucumber, and the intensity of Pb pollution in vegetable-cultivating district in Xian suburb was ：western〉northern〉eastern〉southern.