关键词: 重金属, 土壤, 蔬菜, 公路, 崇明岛

Abstract: To study heavy metals(lead,cadmium,copper and zinc) contamination of soils and vegetables on roadsides,samples of soils,vegetables and dust were collected alongside the Chenhai and Beiyan highways on the Chongming Island for analysis of Pb,Cd,Cu and Zn contents.With the upper limit of the background values of Shanghai set as criterion for evaluation,10.1%、25.4%、6.5% and 8.7% of the soil samples exceeded the criterion for Pb,Cd,Cu and Zn,respectively.When the evaluation was based on the criteria in the farmland environmental quality evaluation standards for edible agricultural products(HJ 332-2006),21.0% of the soil samples were beyond the criterion for Cd,less than 3% beyond the criterion for Pb,but none beyond the criterion for the other two.And when the vegetable samples were evaluated based on the national tolerance limit of heavy metals in foods,43.2% exceeded the criterion for Pb,18.6% for Cd and less than 5% for Zn and Cu.All the findings suggest that the soils and vegetables,within 50 m,alongside the roads low in traffic load will get contaminated with heavy metals after long terms of road service. Flying dust is an important potential source of heavy metal contamination in the roadside environment.

Key words: heavy metal, soil, vegetable, road, Chongming Island