中文摘要：

目的探讨贵阳市道路降尘中重金属污染水平及健康风险状况。方法采集贵阳市主城区道路32个采样点的降尘样品，测定降尘中4种重金属铜（Cu）、铅（Pb）、锌（Zn）、砷（As）含量，并采用地质累积指数（Igeo）法、健康风险评价模型和Spearman相关分析，分别对重金属污染程度、人体健康风险及污染来源进行分析。结果降尘中Cu、Pb、Zn和As含量分别为60．37～437．79、35．63～313．52、282．64～841．57、8．70～23．74mg／kg，其中Cu、Pb和Zn平均含量分别为贵州土壤背景值的7．69、2．85和6．94倍，As未超过背景值。Igeo为Cu〉Zn〉Pb〉As，其中Cu与Zn分别为2．24和2．17，为中度污染。健康风险评价表明道路降尘中重金属的非致癌风险依次为As〉Pb〉Cu〉Zn，但风险较小或可忽略。降尘中Cu和Zn含量呈正相关（r=0．582，P〈0．01）。结论贵阳市道路降尘中的Cu、Zn污染水平较高，其健康风险尚在可接受范围内，但仍需加强监测。

英文摘要：

Objective To explore the level and health risk of road dust＇s heavy metal pollution in the main streets of Guiyang. Methods A total of 32 dust samples were collected in the main intersection of Guiyang, and copper, lead, zinc, arsenic were measured. The heavy metal pollution, human health risks and their source were analyzed by using the geoaccumulation index, risk assessment models and Spearman correlation coefficient. Results The levels of copper, lead, zinc and arsenic in dust were 60.37-437.39, 35.63-313.52, 282.64-841.57, 8.70-23.74 mg/kg. The levels of copper,lead and zinc were 7.69, 2.85 and 6.94 times as higher as the average background value in soil in Guizhou respectively, but arsenic was lower than the background value. The Igeo ranked as copper〉zinc〉lead〉arsenic, and copper （Igeo： 2.24） and zinc （Igeo ： 2.17 ） revealed moderate pollution. Non- carcinogenic risk ranked as arsenic〉lead〉copper〉zinc, which did not exist a significant risk. The levels of copper in dust were positively correlated with zinc （r=0.582,P〈0.01）. Conclusion The levels of copper and zinc in dust from the main streets of Guiyang are higher, and the health risks are acceptable, but the prevention should be enhanced.