Dusty cities, smoky skies, and old paint: air quality, climate, health, and cultural impacts of chemistry at atmospheric interfaces

尘土飞扬的城市、烟雾缭绕的天空和旧油漆：大气界面化学对空气质量、气候、健康和文化的影响

• 批准号: RGPIN-2021-04383
• 负责人: Styler, Sarah
• 金额: $ 2.11万
• 依托单位: McMaster University
• 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=748256
• 关键词: Dusty; cities; smoky; skies; old

Atmospheric particulate matter (PM) influences Earth's climate, contributes to air quality reductions, and provides a surface for chemical reactions; these reactions, in turn, can influence the abundance of pollutant gases (e.g. O3 and NO2) and the fate of PM-associated species. Here, we propose research in four linked themes, each of which explores a different aspect of chemistry at atmospheric interfaces: 1-Photochemistry of dust and non--exhaust PM: implications for pollutant fate, PM composition, and urban air quality As vehicle emission regulations tighten, the contribution of non-exhaust sources (e.g. road dust, brake/tire wear) to urban PM loadings will increase. We propose to study a) reactive oxidant production by road dust, and the implications of this production for the fate of urban contaminants; b) the influence of dust--catalyzed organic transformations on PM composition and properties; and c) the impact of road dust/non--exhaust PM chemistry on the gas-phase composition of the urban atmosphere. 2-Climate, air quality, and health impacts of boreal wildfires Boreal wildfires are increasing in both frequency and intensity. We propose to a) quantify the conversion of NO2 to nitrous acid (HONO), an important atmospheric oxidant precursor, by boreal wildfire PM; b) apply size-exclusion chromatography coupled with UV-Vis detection to investigate the light--absorbing (i.e. climate--relevant) properties of this PM as a function of combustion conditions; and c) assess the lifetime and fate of toxic contaminants at the surface of wildfire ash. 3-New high--throughput instrumentation for study of PM-pollutant interactions In Themes 1 and 2, we quantify gas-surface interactions using flow tube instrumentation, which enables the detailed study of individual pollutant-substrate pairs. However, this approach is too time-consuming to permit exploratory (i.e. non-targeted) study of large PM sample sets. Motivated by medicinal and materials chemistry approaches to drug discovery and catalyst screening, we propose to a) develop and validate a new high--throughput modular photoreactor for study of pollutant gas-PM interactions; and b) apply this reactor to uncover predictive relationships between PM composition/properties and reactivity. 4-Exploring air quality challenges in museum environments Cultural heritage objects are displayed and stored in microclimate-like environments (e.g. frames and storage crates) and are thus susceptible to damage by emissions from enclosure materials (e.g. formaldehyde, acetic/formic acid). We propose to apply strategies developed in Themes 1-3 to a) quantify potential biases associated with formic acid sampling in museum environments; b) obtain kinetic data for gas-surface pairs relevant to museum storage environments; and c) implement these data in simple microclimate enclosure models, which will enable us to better interpret/apply pollutant measurements obtained in museum air quality campaigns.

大气颗粒物（PM）影响地球气候，导致空气质量下降，并为化学反应提供表面;这些反应反过来又会影响污染气体（如O3和NO2）的丰度和PM相关物种的命运。在这里，我们提出了四个相关主题的研究，每个主题都探索了大气界面化学的不同方面：1-灰尘和非排气PM的光化学：对污染物命运，PM成分和城市空气质量的影响随着车辆排放法规的收紧，非排气源（如道路灰尘，刹车/轮胎磨损）对城市PM负荷的贡献将增加。我们建议研究a）由道路灰尘产生的活性氧化剂，以及这种生产对城市污染物命运的影响; B）灰尘催化的有机转化对PM组成和性质的影响;以及c）道路灰尘/非排气PM化学对城市大气气相组成的影响。2-气候，空气质量和北方野火的健康影响北方野火的频率和强度都在增加。我们建议a）量化NO2到亚硝酸（HONO），一个重要的大气氧化剂前体，由北方野火PM的转化; B）应用尺寸排阻色谱法结合紫外-可见光检测，以调查光吸收（即气候相关）属性的PM作为燃烧条件的函数;和c）评估野火灰表面的有毒污染物的寿命和命运。3-新的高通量仪器用于研究PM-污染物的相互作用在主题1和2中，我们使用流管仪器量化气体-表面相互作用，这使得单独的污染物-基质对的详细研究成为可能。然而，这种方法太耗时，无法进行探索性研究。（即非靶向）大颗粒物样品组的研究。受药物和材料化学方法的药物发现和催化剂筛选的启发，我们提出a）开发和验证一种新的高通量模块化光反应器，用于研究污染气体-颗粒物相互作用;和B）应用该反应器以揭示PM组成/性质与反应性之间的预测关系。4-探索博物馆环境中的空气质量挑战文化遗产物品在类似小气候的环境中展示和储存（例如框架和储存板条箱），因此容易受到外壳材料排放物的损坏（例如甲醛、醋酸/甲酸）。我们建议应用主题1-3中开发的策略来a）量化与博物馆环境中甲酸采样相关的潜在偏差; B）获得与博物馆存储环境相关的气体-表面对的动力学数据;以及c）将这些数据应用于简单的小气候封闭模型，这将使我们能够更好地解释/应用在博物馆空气质量活动中获得的污染物测量结果。