Sunlight and tire wear particles - a toxic combination? Evaluating mechanisms for mobilization and degradation of tire particle compounds

阳光和轮胎磨损颗粒——有毒的组合？

• 批准号: 2327008
• 负责人: Natalie Mladenov
• 金额: $ 41.99万
• 依托单位: San Diego State University Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2327008&HistoricalAwards=false
• 关键词: Sunlight; tire; wear; particles; toxic

Tire wear particles (TWP) are released from abrasion of tires on roadways and are one of the most abundant forms of microplastic pollutants. More than one million metric tons of TWP are flushed into waterways each year, with devastating impacts for fish and other aquatic organisms. While sunlight exposure may break down some of the compounds leached from TWP, some compounds will persist in the environment, and new compounds and more toxic transformation products also will form. Many of the TWP compounds that leach into water are not yet known, and the effects of sunlight on TWP compound leaching, toxicity, and fate also remain unknown. The goal of this project is to address major gaps in our knowledge of 1) the many organic compounds that leach from TWP, 2) which TWP-derived chemicals should be prioritized for further study based on their toxicity, and 3) how sunlight transforms and degrades different TWP compounds in water. The research team will identify the diverse compounds leached from tread particles from different tire types under solar exposure and dark conditions, describe their toxicity, and evaluate the persistence and decay of TWP compounds in the presence of simulated sunlight. The successful completion of this project will benefit society through the generation of fundamental knowledge about the toxicity of different tire wear particles which could inform future legislation related to tire manufacture, tire recycling, and green infrastructure for stormwater quality. Additional benefits to society will be achieved through student education and training including the mentoring of two graduate students at San Diego State University.The accumulation of tire wear particles (TWP) in watersheds has emerged as major threat for aquatic ecosystems, with TWPs in water being linked directly to urban runoff mortality syndrome for fish and macroinvertebrates. Given that some tire formulations contain as little as 20% natural rubber but have a vast array of synthetic polymers, metals, and additives, many of the TWP-derived compounds and transformation products that may be leached into the water column are not yet known and their toxicity has not been established - especially the ones that form via direct or indirect photolysis. Some leached compounds and transformation products from TWP will be photo-resistant and persist in the environment while others will decay rapidly, and determining the kinetics of leaching and photochemical degradation on a compound-by-compound basis is a challenge. The overarching goal of the proposed research is to evaluate the fundamental processes that control the production of toxic TWP-derived compounds and transformation products. The specific objectives are to 1) probe the effects of both direct and indirect photolysis on leaching, transformation, and persistence of toxic micropollutants from TWPs, 2) elucidate the role of reactive intermediates in these processes, and 3) develop kinetic models for decay of TWP-derived compounds. Experiments will be performed using a variety of samples from passenger cars and high-performance tires, which have different chemical compositions and in different conditions, sunlight and dark. The successful completion of this research has the potential for transformative impact through the mechanistic understanding of the role of sunlight in the formation and destruction of TWP-derived compounds. To implement the education and training goals of the project, graduate students will lead high impact experiences and outreach activities in coordination with the Math Engineering and Science Achievement (MESA) program, including STEM Shadow Day, the “Stormwater Debris Capture Device Competition” for K-12 students, and mentoring undergraduates through the MESA Summer Academy. In addition, the PIs plan to brief California State policymakers on research findings through the CSU COAST Program network.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

轮胎磨损颗粒（TWP）是从道路上的轮胎磨损中释放出来的，是最丰富的微型污染物之一。每年，超过一百万吨的TWP被冲入水道，对鱼类和其他水生生物产生毁灭性的影响。虽然阳光暴露可能会破坏一些从TWP步行的化合物，但某些化合物将在环境中持续存在，新化合物和更多有毒的转化产品也将形成。许多走进水中的TWP化合物尚不清楚，阳光对TWP化合物步行，毒性和命运的影响也尚不清楚。该项目的目的是解决我们了解的主要差距1）从TWP步行的许多有机化合物，2）应根据其毒性优先考虑TWP衍生的化学物质，以及3）3）阳光如何转化和降解在水中的不同TWP。研究小组将确定在太阳暴露和黑暗条件下从不同轮胎类型的胎面颗粒中走的不同化合物，描述其毒性，并评估在存在模拟阳光下TWP化合物的持久性和衰变。该项目的成功完成将通过产生有关不同轮胎磨损颗粒的毒性的基本知识来使社会受益，这些知识可以为与轮胎制造，轮胎回收和绿色基础设施有关的雨水质量相关的未来立法提供信息。将通过学生的教育和培训来实现社会的额外好处，包括在圣地亚哥州立大学的两名研究生的心理。在流域中，轮胎磨损颗粒（TWP）的积累已成为水生生态系统的主要威胁，在水中，TWP与鱼类和小型无线电verse的城市径流综合症直接链接到水中。鉴于某些轮胎配方含量只有20％的天然橡胶，但具有大量的合成聚合物，金属和添加剂，因此许多TWP衍生的化合物和转化产品可能尚不清楚，并且尚不知道它们的毒性，尚未确定它们通过直接或无调光电分析形成的毒性。来自TWP的一些步行化合物和转化产品将具有光合作用并在环境中持续存在，而另一些则将迅速腐烂，并且在复合基础上确定步行和光化学降解的动力学是一个挑战。拟议研究的总体目标是评估控制有毒TWP衍生化合物和转化产品的基本过程。特定目标是1）探测直接和间接光解对TWPS的有毒微污染物的行走，转化和持久性的影响，2）阐明反应性中间体在这些过程中的作用，以及3）为TWP衍生化合物的衰变而开发动力学模型。将使用来自乘用车和高性能轮胎的各种样品进行实验，这些轮胎具有不同的化学成分，并且在不同的条件下，阳光和黑暗。这项研究的成功完成具有通过对阳光在TWP衍生化合物的形成和破坏中的作用的机械理解来实现变革性影响的。为了实施该项目的教育和培训目标，研究生将在与数学工程和科学成就（MESA）计划（包括STEM Shadow Day，K-12学生的“雨水碎片捕获设备竞争”）以及通过MESA Summer Academy通过毕业生的“ STEM WATER碎片捕获器械竞争”，领导高影响力经验和外展活动。此外，PIS计划通过CSU Coast计划网络将加利福尼亚州政策制定者简要介绍研究结果。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，被认为是通过评估而被视为珍贵的支持。