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: $ 3.64万
• 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: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=753254
• 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.

道路灰尘是一系列金属和类金属的汇，这些金属和类金属是由交通相关活动以排气（尾气管）和非排气（街道表面、汽车部件等的磨损及其再悬浮）形式排放的。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原因。迄今为止的证据表明，道路灰尘中较细的颗粒级分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表征了粒径>63微米的道路灰尘的化学组成，但在以下方面存在很大的数据缺口：1。与交通相关的颗粒和金属对道路的总负荷，2.元素富集模式作为粒径分数和相关的潜力的函数被动员通过再悬浮过程和，3。特定汽车和街道磨损源对能够被吸入的道路灰尘颗粒尺寸分数的贡献。这阻碍了对城市环境中与道路灰尘相关的元素通量进行估计，也阻碍了为管理和减排目的确定作为颗粒大小贡献和潜在毒性函数的源排放。特别是，缺乏有关稀土和铂族元素等新兴金属的浓度和道路灰尘富集模式的数据。拟议的研究将系统地研究从不同交通量、车队组成等的各种道路收集的道路灰尘的颗粒大小质量分布和相关金属和准金属富集，在大多伦多地区。将检查总道路灰尘样品的粒度分布，以估计人类和环境健康关注的细组分对沉积在各种类型道路上的总量的质量贡献。将确定未分级和分级道路灰尘样品的金属和准金属浓度，以计算街道的元素负荷和通量估计。这些数据可作为开发模型的基础，以评估道路灰尘中的移动的部分在多大程度上可能在更大的空间尺度上造成城市空气污染和污染。