道路环境PGEs多介质累积规律

Accumulation Characteristics of PGEs in Multimedia from Road Environment

为了研究道路环境PGEs多介质累积规律,选择上海市5条道路,同步采集灰尘、土壤及植物样品,对其中铂族元素(PGEs)含量水平进行分析.结果表明,灰尘中Rh、Pd、Pt平均浓度分别为24.92、88.39、22.28 ng/g,土壤中Rh、Pd、Pt平均浓度分别为3.64、17.45、0.97 ng/g,植物中Rh、Pd、Pt平均浓度仅分别达到2.66、6.39、0.57 ng/g,灰尘PGEs浓度远高于土壤及植物,土壤与植物中Pt、Rh浓度水平较接近;道路环境PGEs分布呈现一定规律性,但与交通流量关系并不密切;路边植物对道路灰尘PGEs吸附能力表现为Pt>Pd>Rh,其中,对Pt、Pd吸附作用非常明显,对Rh几乎不存在吸附作用,路边植物对土壤PGEs的吸收能力为Pd>Rh>Pt,Pd的生物有效性最大;多介质PGEs比例值很接近或部分重合,且均在上海市道路灰尘PGEs比值范围内,反映出上海市道路环境PGEs来源相同且均来自汽车VECs.

In order to study accumulation characteristics of PGEs in multimedia from road environment,samples of road dust, roadside soil and plant were collected from five roads in Shanghai,and were analysed by ICP-MS following aqua regia digestion.The results are as following： average concentrations of Rh,Pd and Pt were 24.92,88.39,22.28ng/g in dust,3.64,17.45,0.97ng/g in soil and 2.66,6.39,0.57ng/g in plant,respectively.The concentrations of PGEs in dust were higher than that in soil and in plant.Meanwhile,PGEs concentrations in plant were lower than that in dust,and closed to that of soil.The implementation of the automobile emission standard only in central city of Shanghai didn＇t cause obvious correlation between PGEs in multimedia and traffic volume.The plant adsorption capacity for PGEs of road dust showed： Pt〉Pd〉Rh,while its absorptive capacity for PGEs of soil was： Pd〉Rh〉Pt.PGEs ratios in multimedia were not completely coincident but in the range of PGEs ratios of road dust in Shanghai,which indicated a common traffic-related source of these metals.