Characterizing the elemental enrichment patterns of fractionated road dust and fluxes in the environment

表征环境中分馏道路灰尘和通量的元素富集模式

• 批准号: RGPIN-2018-05966
• 负责人: Wiseman, Clare
• 金额: $ 1.82万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713970
• 关键词: Characterizing; elemental; enrichment; patterns; fractionated

Road dust is a sink for a range of metals and metalloids emitted from traffic-related activity in both exhaust (tailpipe) and non-exhaust (wear of street surfaces, automotive components, etc. and their resuspension) forms. As a pollutant sink, road dust is a likely major contributor to local air, water and soil contamination. The evidence to date suggests the finer particle size fractions of road dust have a high potential to be mobilized via resuspension processes and impact local air quality. While the chemical composition of road dust in particle size fractions >63 microns has been well-characterized in a number of studies, there are large data gaps on the following: 1. total traffic-associated particle and metal loadings to roads, 2. elemental enrichment patterns as a function of particle size fraction and associated potential to be mobilized via resuspension processes and, 3. the contribution of specific automotive and street wear sources to road dust particle size fractions capable of being inhaled. This hinders an estimation of road dust-associated elemental fluxes in an urban context and the identification of source emissions as a function of particle size contribution and potential toxicity for management and abatement purposes. In particular, data is lacking regarding the concentrations and road dust enrichment patterns of emerging metals of concern such as rare earths and platinum group elements. The proposed research will systematically examine the particle size mass distribution and associated metal and metalloid enrichment of road dust collected from a variety of roads with different traffic volumes, fleet composition, etc., in the Greater Toronto Area. The particle size distribution of total road dust samples will be examined to estimate the mass contribution of fine fractions of human and environmental health concern to total amounts deposited on roads of various types. Metal and metalloid concentrations will be determined for unfractionated and fractionated road dust samples for the calculation of elemental loading to streets and flux estimates. The data serve as a basis for development of a model to assess the extent to which mobile fractions of road dust may contribute to urban air pollution and contamination on a wider spatial scale.

道路粉尘是从与交通有关的活动中以废气(尾气)和非废气(街道表面、汽车部件等的磨损及其再悬浮)形式排放的一系列金属和类金属的水槽。作为污染物汇，道路灰尘可能是当地空气、水和土壤污染的主要贡献者。到目前为止的证据表明，细小的道路灰尘颗粒很有可能通过再悬浮过程被动员起来，并影响当地的空气质量。虽然在一些研究中已经很好地描述了颗粒级的道路粉尘的化学成分，但在以下方面仍有很大的数据空白：1.道路上与交通有关的颗粒和金属总负载量，2.作为颗粒级和通过再悬浮过程动员的相关潜力的函数的元素浓缩模式，以及3.特定的汽车和街道磨损源对能够吸入的道路粉尘颗粒级数的贡献。这妨碍了对城市中与道路粉尘有关的元素通量的估计，以及为管理和减少目的而确定作为颗粒大小贡献和潜在毒性函数的源排放。特别是，缺乏关于稀土和铂族元素等令人关切的新兴金属的浓度和道路粉尘浓缩模式的数据。 拟议的研究将系统地研究从大多伦多地区不同交通量、车队组成等不同道路收集的道路粉尘的颗粒质量分布和相关的金属和金属类物质浓缩。我们会研究道路总尘埃样本的粒度分布，以评估人类和环境健康所涉及的细小成分对各类道路上所沉积的总沉降量的质量贡献。将测定未分馏和分馏的道路粉尘样品的金属和类金属浓度，用于计算街道上的元素负荷和流量估计。这些数据作为开发模型的基础，以评估可移动的道路灰尘在多大程度上对城市空气污染和更广泛的空间范围内的污染作出贡献。