大冶市街尘重金属污染评价及化学形态特征  

The level and speciation of metals in street dusts of Daye,Hubei Province

作　　者：韩晓涛[1] 郭宇[1,2] 鲍征宇[1,3] 周树达[1] 

机构地区：[1]中国地质大学地球科学学院研究生院,湖北武汉430074 [2]广州市地质调查院,广东广州510440 [3]中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉430074

出　　处：《地球化学》2012年第6期585-592,共8页Geochimica

基　　金：国家自然科学基金(40872195)

摘　　要：以矿冶城市大冶市为例,结合街尘pH及矿物相,研究矿山活动影响下的2个典型区(靠近矿区的铜绿山镇和相对远离矿区的大冶市区)街尘中重金属(Cd、Pb、Cu)污染现状及化学赋存形态。地累积指数显示,铜绿山镇重金属处于严重污染水平,大冶市区处于重污染水平,其中Cd和Cu相对于Pb污染较严重。重金属BCR形态表明,铜绿山镇Cd以可氧化态和可还原态为主,大冶市区Cd四态比例基本相同;Pb在铜绿山镇以残渣态和可氧化态为主,而在大冶市区以弱酸态和可氧化态为主;Cu在两研究区均以可氧化态为主。Pb和Cd生物活性较大,对环境危害较高,Cu相对较低。The pH, XRD and total concentrations of three metals （Cd, Pb, Cu） were analyzed on street dust samples collected from two different locations （Tonglushan and Urban） situated in Daye and. Results showed that the heavy metal pollutions in Tonglushan and Urban were generally high. The modified three-step BCR sequential extraction procedure was used to evaluate the mobility and bioavailability of metals. Results demonstrated that Cd was mainly distributed in the oxidizable and reducible fractions in the dust of Tonglushan, while these four fractions were at the same level in dusts of Urban. Pb was largely associated with residual and oxidizable in Tonglushan, however, the exchangeable and oxidizable fractions of Pb were also detected in Urban. Cu was predominantly in the oxidizable fraction in both locations. The high labile fraction of Pb and Cd need to be paid more attention.

关 键 词：街尘 重金属 BCR形态 地累积指数 大冶 

分 类 号：P595[天文地球—地球化学] X142[天文地球—地质学]