Sources and Impacts of Water-Soluble Iron in Atmospheric Aerosol

尽管水溶性（WS）含铁气溶胶气候、空气质量和人类健康具有重要意义，但控制其大气浓度的来源和化学成分尚未得到很好的了解。特别是，为数不多的环境观测表明，在大多数人口居住的陆地上，含有ws - fe的气溶胶具有特征。因此，人类对WS-Fe的潜在暴露没有得到很好的表征。虽然大气模型表明，燃烧气溶胶的化学性质可以调和全球WS-Fe收支，但对这种化学性质的基本理解对于准确评估和预测WS-Fe的环境影响是必要的。本研究计划旨在全面了解WS-Fe及其他有毒金属在室外及室内气溶胶中的来源及影响。这将通过机械实验室实验和环境观测相结合来实现。初步项目将：1)表征室外和室内燃烧活动排放的气溶胶中WS-Fe浓度；2)确定各种促进铁溶解的反应（如酸催化和络合反应）对室外燃烧气溶胶的化学处理中WS-Fe的产率；3)在新不伦瑞克省萨克维尔市建立空气质量监测点；4)确定全国环境WS-Fe浓度的主要来源和化学生成机制。这项研究计划不仅将对加拿大以前实施的空气质量法规（如逐步淘汰燃煤电厂）进行追溯性评估，而且还将支持设计更有效的缓解战略，并更准确地预测由于排放变化而产生的未来影响。这是非常重要的，因为燃烧活动，如加拿大森林的野火，预计会增加。这项工作的另一个关键影响是评估与加热和烹饪有关的燃烧活动所排放的室内气溶胶中有毒成分的潜在暴露。这项工作的结果与居住在农村社区的加拿大人直接相关，在农村社区，木材燃烧仍然是主要的住宅能源。该研究项目还将为新兴的年轻科学家提供跨学科的培训场所。学生不仅将发展多样化的分析技能，还将通过实验室实验和实地观察拓宽他们的研究经验。他们也将有机会与其他部门、机构和政府机构的成员合作。

Despite the importance of water-soluble (WS) Fe-containing aerosol climate, air quality, and human health, the sources and chemistry governing its atmospheric concentrations are not well understood. In particular, a scarce number of ambient observations have characterized WS-Fe-containing aerosol over land on which most human populations reside. Thus, the potential human exposure of WS-Fe is poorly characterized. While atmospheric models have suggested that the chemistry of combustion aerosol may reconcile the global WS-Fe budget, a fundamental understanding of this chemistry is necessary for accurate assessments and predictions of the environmental impacts of WS-Fe. The goal of the proposed research program is to develop a comprehensive understanding of the sources and impacts of WS-Fe and other toxic metals in outdoor and indoor aerosol. This will be achieved through a combination of mechanistic laboratory experiments and ambient observations. Initial projects will: 1) characterize the WS-Fe concentrations in aerosol emitted from both outdoor and indoor combustion activities; 2) determine the production rates of WS-Fe from the chemical processing of outdoor combustion aerosol caused by various reactions (such as acid-catalyzed and complexation) that can promote iron dissolution; 3) establish an air quality monitoring site in Sackville, New Brunswick; and 4) identify the major sources and chemical production mechanisms governing the ambient concentrations of WS-Fe nation-wide. This research program will not only result in retroactive evaluation of previously implemented air quality regulations in Canada (such as phase out of coal-fired power plants), but also support the design of more efficient mitigation strategies and more accurate predictions of future impacts due to changes in emission. This is very important given that combustion activities, such as wildfires in Canadian forests, are expected to increase. Another critical impact of the work is the evaluation of potential exposure to toxic components in indoor aerosol emitted by heating- and cooking-related combustion activities. The results from this work are of direct relevance to Canadians living in rural communities where wood combustion remains a predominant residential energy source. The research program will also provide an interdisciplinary training ground for emerging young scientists. Students will develop not only a diverse analytical skill set, but also broaden their research experience through exposure to both laboratory experiments and field observations. They will also have the opportunity to collaborate with members from other departments, institutions, and government agencies.