Antimony derived from brake linings in roadside soils, road run-off, and affected streams

来自路边土壤、道路径流和受影响溪流中的刹车片的锑

• 批准号: 270959057
• 负责人: Professor Dr. Tim Mansfeldt
• 金额: --
• 依托单位: Geographisches Institut
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/270959057?language=en
• 关键词: Antimony; derived; brake; linings; roadside

Antimony (Sb) and its compounds are considered as a pollutant of high priority interest by national and international environmental authorities (e.g., WHO, US E.P.A., Council of the European Communities) as they have carcinogenic potential. Nevertheless, this semimetal is added to friction material in brake linings and released into the environment due to abrasion during the braking process. The objectives of this proposal are (i) to yield detailed information about the spatial distribution patterns of total Sb in thoroughly characterized roadside soils, and (ii) to provide an improved understanding of Sb's mobility and speciation (tri- versus pentavalent Sb) and its spatial distribution patterns in those. Besides the determination of total Sb by microwave digestion using strong mineral acids, a sequential extraction procedure will be applied to assess the mobility and bioavailability of Sb. The procedure includes the determination of the weak acid-soluble, reducible, oxidizable, and residual fractions. To determine Sb(III) and Sb(V), a reliable quantitative extraction of Sb from the sample matrix must be applied without any degradation or transformation of its species, but still with representative extraction efficiency. We will apply and adjust already tested extraction methods to a wider range and variation of soil samples in order to develop a less matrix-dependent procedure. Moreover, the (iii) speciation and size fractionation of Sb in road run-off, and (iv) the effects of discharged road run-off on the speciation and size fractionation of Sb in a drainage stream will be investigated. Variations in water quality parameter such as pH, ionic strength, redox potential, temperature, and dissolved oxygen have an influence on metal speciation in aquatic systems. We will study these effects by conducting speciation and size fractionation in both road run-offs during rain events, and long-term variations in a drainage system downstream of an outlet of road run-off. Size fractionation will provide more information about binding forms of Sb in aquatic systems. It is known that Sb mainly remains in the low molecular mass (LMM) fraction. This is of great concern, as LMM species are believed to be more bioavailable than particle-associated species. Nevertheless, both analytical approaches have never been conducted in roadside run-off and its affected drainage system. All these objectives share a common purpose: to provide a better understanding of how brake-lining-derived Sb is present in roadside soils and related drainage systems. Distribution of Sb species in environmental samples is crucial for the evaluation of toxic effects, since Sb toxicity depends on its oxidation state.

锑（SB）及其化合物被认为是具有致癌潜力的国家和国际环境当局（例如，美国E.P.A.，欧洲社区理事会）被视为高优先级利益的污染物。然而，该半学被添加到制动衬里的摩擦材料中，并在制动过程中由于磨损而释放到环境中。该提案的目标是（i）在彻底表征的路边土壤中产生有关总SB的空间分布模式的详细信息，以及（ii）为了提高对SB的迁移率和物种形成性（Tri-ti-ti-ti-versus sb）及其空间分布模式的了解。除了使用强矿酸通过微波消化测定总SB外，还将采用顺序提取程序来评估SB的迁移率和生物利用度。该过程包括确定弱酸溶剂，可还原，可氧化和残留分数。为了确定SB（III）和SB（V），必须从样品矩阵中使用SB可靠的定量提取，而无需任何降解或转化其物种，但仍具有代表性的提取效率。我们将应用并调整已经测试的提取方法，以更广泛的范围和土壤样品的变化，以制定依赖矩阵依赖的过程。此外，将研究（III）在道路径流中SB的（III）形成和大小分馏，（iv）将研究排出的道路径流对排水流中SB的物种形成和大小分馏的影响。水质参数的变化，例如pH，离子强度，氧化还原电位，温度和溶解氧对水生系统中的金属形成有影响。我们将通过在降雨事件期间在两个道路径流中进行物种形成和大小分馏来研究这些效果，以及在道路径流出口下游的排水系统中的长期变化。尺寸分馏将提供有关水生系统中SB结合形式的更多信息。众所周知，SB主要保留在低分子质量（LMM）中。这是非常关注的问题，因为据信LMM物种比粒子相关物种更具生物利用度。然而，在路边径流及其影响的排水系统中，从未采用过两种分析方法。所有这些目标都有一个共同的目的：更好地了解路边土壤和相关排水系统中如何存在制动层衍生的SB。 SB物种在环境样品中的分布对于评估毒性作用至关重要，因为SB毒性取决于其氧化态。