Collaborative Research: Impact of Metals on Photochemical Aging of Water Soluble Organic Carbon in Atmospheric Particulate Matter: A Combined Lab and Field Study

点击翻译按钮获取中文摘要

This study is focused on improving the understanding of the interactions between soluble iron (Fe) and organic material in fine particles in the atmosphere. This research is relevant to the larger question of how atmospheric iron affects the processing and aging of the organics in atmospheric particulate matter. The results will provide information useful to atmospheric chemists and to environmental health professionals.The project will examine the importance of the Fe-assisted oxidation route of water-soluble organic carbon. It consists of three tasks: (1) field sampling, (2) characterization of the particulate matter, and (3) photochemical laboratory experiments. The field samples will be analyzed to assess the sources of the atmospheric Fe, since the source of the Fe may determine its chemical speciation and, thus, its solubility and availability to chemical reactions. Aqueous extracts of the field samples will be subjected to an artificial aging process and undergo analysis for oxidation state and the chemical speciation of total iron, and the production of reactive oxygen species will be quantified. By investigating the role of transition metals and taking into account aqueous chemistry, this project will offer a more complete picture of how organic compounds are "aged" in the atmosphere. The results will provide useful information on the role iron plays in the processing of organic compounds in atmospheric particulate matter and the potential impacts of these mixed particles on human health.