内江市郊区菜园土壤和蔬菜重金属污染及其评价

Assessment of Heavy Metal Pollution in Vegetables and Vegetable Garden Soil in Suburban Neijiang

对内江市郊区菜园土壤和白菜、韭菜、胡萝卜、白萝卜、茄子、莴笋、芹菜、豇豆和冬瓜等9种蔬菜中5种重金属的含量和污染状况进行分析评价.结果表明:内江市郊区菜园土壤Cu,Zn,Pb,Cd和Cr的平均含量分别为77.53,165.17,0.147,92.34,79.56mg/kg,是四川土壤背景值的249.28%,190.97%,298.83%,185.65%,100.70%,Cu,Pb,Zn元素污染属轻度污染,其中Pb较接近中度污染;Cr属警戒级;Cd为安全级.重金属元素Cu,Pb,Zn的复合污染较普遍.内江市郊区蔬菜的重金属Cu,Zn,Pb,Cd和Cr含量排序为Zn>Cu>Pb>Cr>Cd;9种蔬菜对重金属元素的富集效应大体为Cd>Zn>Cu>Pb>Cr;除Pb含量在白菜、豇豆、莴笋和芹菜中超标外,其他元素在各蔬菜中均无超标现象.

Heavy metal pollution in vegetable garden soil and vegetables such as cabbage, leek, carrot, radish, brinjaul, lettuce, celery, cowpea, Chinese watermelon in suburban Neijinag was analyzed and assessed. The results indicated that the average contents of Cu, Zn, Pb, Cd and Cr in the vegetable garden soil of suburban Neijiang were 77. 53 mg/kg, 165.17 mg/kg, 0. 147 mg/kg, 92. 34 mg/kg and 79. 56 mg/kg respectively, which, in eomparision, were 249. 28%, 190. 97%, 298. 83%, 185.65%, 100.70% of the soil background values in Sichuan province, showing that the soil has been lightly Cu-, Pb and Zn-polluted and heavily Cd-polluted, and combined pollution of Cu, Pb ＆ Zn was common in the soil. The heavy metal contents of vegetables rank in the order of Zn〉Cu〉Pb〉Cr〉 Cd, and the order of the heavy metal enrichment coefficients for the nine kinds of vegetables was as follows Cd〉 Zn〉Cu〉Pb〉Cr. Many elements＇ concentration in vegetables did not exceed the national vegetable sanitation standard except that of Pb in cabbage, cowpea, lettuce and celery.