Evaluation of the health impacts of aircraft nanoparticles using a surrogate soot source and in vitro cell exposure

飞机发动机排放的污染物会降低机场周围的空气质量，这可能会影响当地居民和机场员工的健康。具体地，从燃气涡轮机发动机排放的纳米颗粒包括烟灰聚集体、硫化合物、半挥发性有机碳和金属灰。随着飞机发动机喷射流冷却并与周围大气混合，成核和冷凝过程导致成核模式颗粒的快速增长以及半挥发性化合物冷凝到非挥发性烟灰聚集体上。飞机纳米颗粒排放的特点是相对于其他燃烧源（如公路运输）而言，其尺寸较小（<60 nm）。因此，它们可能对健康产生特殊的影响，而这些影响目前尚未得到充分研究和充分了解。很少有研究进行体外毒理学试验，以评估暴露于飞机发动机排放的飞机烟尘对人支气管上皮细胞的影响。我们需要做更多的工作来了解飞机纳米颗粒的不同影响及其不同性质和化学成分的作用。该项目旨在通过开发和实验方法来测试不同尺寸的纳米颗粒和化学成分的细胞反应，从而有助于了解纳米颗粒对健康影响的途径。该项目的具体目标是：1。回顾有关飞机纳米颗粒排放、机场附近纳米颗粒测量以及不同类型和来源的燃烧气溶胶对健康影响的文献，包括细胞反应研究。开发实验室烟尘颗粒源，可用于生成可调的代用飞机气溶胶，包括颗粒尺寸分布和形态、化学成分和不同涂层以及大气老化和氧化。烟尘源将基于以前用作飞机烟尘颗粒替代品的燃烧器设计，并将开发有机碳涂层和大气老化等其他功能。3.使用替代烟尘源设计并进行全面的实验矩阵，以评估细胞对颗粒尺寸和形态、涂层化学成分和大气老化的反应。例如，气溶胶分类器可以在沉积在细胞培养物上之前分离特定的颗粒尺寸，以控制颗粒尺寸的影响。类似地，颗粒可以用不同的材料涂覆，或者通过使用催化剥离剂去除它们的涂层。这些方法已经建立，涉及将原代人肺细胞暴露于增加浓度的颗粒并测定细胞活力（MTT/LDH/凋亡测定）、介质产生（即促炎反应; ELISA测定）、氧化应激（ROS测量）、线粒体完整性（mitotracker）、细胞抗氧化剂消耗（GSH氧化）和颗粒摄取。将平行测试具有已知毒性的阳性对照（例如ZnO纳米颗粒）。利用现有的证据和新的建模工作来评估机场周围飞机纳米颗粒排放的潜在健康影响，以了解健康风险如何随距离机场的距离和其他因素（如天气条件）而变化。新的工程/物理科学内容开发颗粒技术技术，以产生具有不同涂层，尺寸，形状的烟尘纳米颗粒工程系统污染的健康影响，特别是飞机发动机排放物。这可以为空气质量标准的制定提供信息。研究理事会主题相关EPSRC主题：工程，能源EPRSC相关研究领域：分析科学，建筑环境，基础设施和城市系统，粒子技术，传感器和仪器

Aircraft engines emit pollutants that degrade the air quality around airports, which may affect the health of local residents and employees at the airport. Specifically, nanoparticles emitted from gas turbine engines comprise soot aggregates, sulphur compounds, semi-volatile organic carbon and metallic ash. As the aircraft engine jet cools and mixes with the surrounding atmosphere, nucleation and condensation processes lead to a rapid growth in nucleation mode particles and condensation of semi-volatile compounds onto non-volatile soot aggregates. Aircraft nanoparticle emissions are characterised by their small size (<60 nm) relative to other combustion sources, e.g. road transport. They may therefore have particular health consequences that are currently under-studied and not well understood. Few studies have conducted in-vitro toxicology tests to evaluate the effects on human bronchial epithelial cells to exposure to aircraft soot emissions from aircraft engines. Much more work is needed to understand the different effects of aircraft nanoparticles and the role of their different properties and chemical constituents.This project aims to contribute to the understanding of the health impacts pathways of nanoparticles by developing and experimental methodology to test cellular responses to different sized nanoparticles and chemical compositions. The specific objectives of the project are to:1. Review the literature on aircraft nanoparticle emissions, nanoparticle measurements near airports, and health impacts of different types and sources of combustion aerosols, including cellular response studies.2. Develop laboratory source of soot particles that can be used to generate a tuneable surrogate aircraft aerosol in terms of particle size distribution and morphology, chemical composition and different coatings, and atmospheric ageing and oxidation. The soot source will be based on a burner design that has been used as a surrogate for aircraft soot particles before, and additional features such as organic carbon coatings and atmospheric ageing will be developed. 3. Use the surrogate soot source to design and conduct a comprehensive matrix of experiments to evaluate cellular responses to particle size and morphology, chemical composition of coatings, and atmospheric ageing. For example, aerosol classifiers could separate particular particle sizes before deposition on the cell culture to control for the effects of particle size. Similarly, particles could be coated with different materials, or have their coating removed by the use of a catalytic stripper. These methods are already established and involve exposure of primary human lung cells to increasing concentrations of the particles and determination of cell viability (MTT/LDH/apoptosis assays), mediator production (ie pro-inflmmatory responses; ELISA assays), oxidative stress (ROS measurement), mitochondrial integrity (mitotracker), cellular antioxidant depletion (GSH oxidation) and particle uptake. Positive controls (eg ZnO nanoparticles) with known toxicity will be tested in parallel.4. Evaluate potential health impacts of aircraft nanoparticle emissions around airports using existing evidence and new modelling works to understand how health risks may vary with distance from the airport, and other factors such as weather conditions.Novel engineering/physical sciences contentDevelopment of particle technology techniques to generate soot nanoparticles with different coatings, sizes, shapesHealth impacts of pollution from engineering systems, specifically aircraft engine emissions. This could inform development of air quality standards. Research council themesRelevant EPSRC themes: Engineering, EnergyRelevant EPRSC research areas: Analytical science, Built environment, Infrastructure and urban systems, Particle technology, Sensors and instrumentation