成都市中心城区街道灰尘中硒赋存形态及生态风险评价  

Speciation and ecological risk of selenium in street dust in downtown Chengdu

作　　者：王昕宇 李晓鑫 高莉维 高越 郎春燕[1] WANG Xinyu;LI Xiaoxin;GAO Liwei;GAO Yue;LANG Chunyan(College of Materials and Chemistry&Chemical Engineering,Chengdu University of Technology,Chengdu,610059,China)

机构地区：[1]成都理工大学材料与化学化工学院,成都610059

出　　处：《环境化学》2022年第6期2014-2021,共8页Environmental Chemistry

摘　　要：以成都市中心城区街道灰尘为研究对象,采集了四种功能区的街道灰尘样品,并过筛分成<97μm和<63μm两种粒径.使用沸水浴王水消解法和改进的BCR顺序提取法对街尘样品中硒的总量及赋存形态进行测定,分析了两种粒径下各功能区硒的分布特征,并运用生态风险评价指数(RAC)法对其生态风险进行评价.结果表明,两种粒径街尘中总硒平均含量分别为0.373 mg·kg^(−1)和0.530 mg·kg^(−1),粒径<97μm街尘中各功能区硒平均含量基本相当,粒径<63μm街尘中教育区域和居住区域硒平均含量更高.相较于粒径<97μm的街尘,在粒径<63μm的街尘中,弱酸提取态硒和可还原态硒的比例均有上升,可氧化态硒占比有所下降.硒在成都市中心城区街尘中主要为低生态风险,但存在中等生态风险地区,并且粒径<63μm比<97μm生态风险更大,需引起注意.Street dust(SD)in downtown Chengdu was investigated,SD samples were collected from four functional areas,and sieved into two particle sizes<97μm and<63μm.Total selenium and species of selenium were determined by using boiling aqua regia digestion method and improved BCR sequential extraction method,and the ecological risk was evaluated by the methods of risk assessment code(RAC).The results showed that the average selenium content of SD with two particle sizes was 0.373 mg·kg^(−1) and 0.530 mg·kg^(−1),respectively.The average selenium content in each functional area of SD with particle size<97μm is basically the same,and the average selenium content in educational area and residential area of SD with particle size<63μm is higher.Compared with the SD with the particle size<97μm,the proportion of acid exchangeable selenium and reducible selenium in the SD with the particle size<63μm increased,while the proportion of oxidizable selenium decreased.Selenium in SD of downtown Chengdu is mainly low ecological risk,but there are moderate ecological risk areas,and the ecological risk of particle size<63μm is greater than<97μm,which should be paid attention to.

关 键 词：硒 赋存形态 街道灰尘 粒径 

分 类 号：X513[环境科学与工程—环境工程] X826