The elemental analysis of road dust can be used to determine the contribution of traffic-related metal emissions to the local environment. Previous studies have shown that brake wear, tire wear, and lead wheel weights release significant amounts of metals that lead to decreased biodiversity and degradation of urban streams. Highway pavement has not previously been considered as a source of metal inputs into the environment. To determine the extent that highway pavement contributes to metal loads in the local environment, road dust and pavement samples were collected for both asphalt and concrete pavement types on State Highway 59 in Houston, TX, USA. Samples were analyzed by ICP-MS to quantitate 9 metals: aluminum (Al), iron (Fe), vanadium (V), chromium (Cr), nickel (Ni), cobalt (Co), copper (Cu), zinc (Zn), and lead (Pb). A chemical mass balance receptor model that is commonly used for source apportionment of air pollution was applied to heavy metals in road dust, with brake dust, tire wear, wheel weights, and pavement materials as the emission sources. Pavement is shown to be the primary source of V, Cr, Ni, and Co in road dust, regardless of asphalt or concrete pavement type. Lead concentration in road dust is influenced by pavement type, with concrete pavement contributing approximately 45% of total lead in concrete road dust, while asphalt pavement only contributes 27% of total lead in asphalt road dust. Fly ash is the likely component of concrete pavement responsible for the higher contribution of Pb. An enrichment factor analysis indicates that Cr, Co, and V have low levels of enrichment compared to Cu, Zn, Pb, and Ni, indicating that pavement wear is generally a minor source of environmental metal contamination compared to brake and tire wear. Currently, brake and tire wear are the non-exhaust vehicle emissions of greatest concern; however, alternatives to fly ash should be considered to further reduce Pb and Ni concentrations in the environment.

道路灰尘的元素分析可用于确定与交通有关的金属排放对当地环境的影响。先前的研究表明，刹车磨损，轮胎磨损和导轮重量会释放出大量金属，从而导致生物多样性减少和城市河流退化。以前，高速公路路面并未被视为环境中金属输入的来源。为了确定高速公路路面对当地环境中金属负载的影响程度，在美国德克萨斯州休斯顿的59号州际公路上收集了沥青和混凝土路面类型的道路灰尘和路面样本。通过ICP-MS分析样品以定量9种金属：铝（Al），铁（Fe），钒（V），铬（Cr），镍（Ni），钴（Co），铜（Cu），锌（Zn） ）和铅（Pb）。将一种通常用于空气污染源分配的化学物质平衡受体模型应用于道路粉尘中的重金属，并以刹车粉尘，轮胎磨损，车轮重量和路面材料作为排放源。无论沥青或混凝土路面类型如何，路面都是道路灰尘中V，Cr，Ni和Co的主要来源。道路粉尘中的铅浓度受路面类型的影响，混凝土路面约占混凝土路面粉尘中铅总量的45％，而沥青路面仅占沥青路面粉尘中铅总量的27％。粉煤灰可能是混凝土路面中铅含量较高的原因之一。富集因子分析表明，与Cu，Zn，Pb和Ni相比，Cr，Co和V具有较低的富集水平，这表明与刹车和轮胎磨损相比，路面磨损通常是环境金属污染的次要来源。当前，制动器和轮胎的磨损是人们最关注的非排气汽车排放。但是，应考虑使用粉煤灰替代品以进一步降低环境中的Pb和Ni浓度。