杭州市大气降尘重金属污染特征及来源研究

Pollution characteristics and sources of heavy metals in atmospheric dustfall of Hangzhou

于2006年6月至2009年6月期间,在杭州市主城区7个采样点对大气降尘进行采集,并对10种重金属元素含量进行了分析。结果表明:重金属元素Cu、Cd、Mn、Ni、Pb、Zn、Co、Al、Fe、Mo质量浓度分别为223.6、15.6、741.1、27.8、363.7、1 820.4、7.0、8 982.4、21 149.0、13.4mg/kg;各功能区差异较大,半山(工业区)Fe、Mn、Pb、Zn浓度较高,江城立交(交通枢纽)Cu、Cd浓度较高。富集因子评价结果表明,Cd、Mo、Pb、Zn、Cu富集程度较高,受到不同程度人为污染。主因子分析结果显示,Mn、Fe可能来自钢铁冶炼及机械制造;Cu、Cd可能来自交通源;Zn、Mo可能来自相关的冶炼加工及合金工业;Ni、Co可能由煤和石油等化石燃料燃烧排放;Pb来自工业排放;Al主要来自地壳。

Atmospheric dustfall were sampled at seven sites in urban Hangzhou, Zhejiang from June 2006 to June 2009.10 heavy metals were measured with the help of inductively coupled plasma （ICP）. The average concentra-tions of Cu,Cd,Mn,Ni,Pb,Zn,Co,A1,Fe and Mo reached 223.6,15.6,741.1,27.8,363.7,1 820.4,7.0,8 982.4, 21 149.0 and 13.4 mg/kg, respectively. Distinct dependence of metal concentrations on regions was observed. In the industrial district （Banshan）, relatively high concentrations of Fe, Mn, Ph and Zn were detected. While in the transpor- tation district （Jiangcheng lijiao） ,Cu and Cd presented the highest level. Enrichment factor analysis indicated that Cd, Mo, Pb, Zn and Cu were mostly contaminated. Major sources were apportioned by using the principle component anal-ysis. Generally,Mn and Fe derived from the steel making. Cu and Cd derived from transportation. Zn and Mo derived from metal industries. Ni and Co derived from fuel combustion. Pb mainly derived from the industrial emission. Earth crust was the main source of Al.