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• 1. [Article] FAGE determination of tropospheric HO and HO₂

  FAGE (fluorescence assay with gas expansion) was developed as a sensitive technique for the detection of low-concentration free radicals in the atmosphere. The application of FAGE to tropospheric hydroxyl ...

  Citation × Citation Citation Abstract Copy Title: FAGE determination of tropospheric HO and HO₂ Author: George, Linda Acha, Hard, Thomas M., O'Brien, Robert J. Year: 1995 FAGE (fluorescence assay with gas expansion) was developed as a sensitive technique for the detection of low-concentration free radicals in the atmosphere. The application of FAGE to tropospheric hydroxyl (H0) and hydroperoxyl (H0₂) radicals has yielded calibrated measurements of both species in both clean air and highly polluted urban air. For HO calibration, a continuously stirred tank reactor provides a uniform external HO concentration, which can be measured by gas chromatography of an HO-reactive hydrocarbon. The aerodynamics of the air-sampling process has been modeled computationally, with results that agree with empirical observations of the effects of nozzle diameter on HO loss during sampling. The authors have also modeled airborne fluid dynamics of a FAGE probe. They have recently obtained FAGE sensitivity as high as ± 1 × 10⁶ cm-³ for a 6-minute averaging period, during field studies in highly polluted Los Angeles air, yielding a 7:1 signal-to-noise ratio near midday. Multipass excitation can further improve this sensitivity. The authors summarize their recent field studies of HO and HO², current work on improved calibration methods, other improvements, and future plans. Title: FAGE determination of tropospheric HO and HO₂ Author: George, Linda Acha, Hard, Thomas M., O'Brien, Robert J. Year: 1995 FAGE (fluorescence assay with gas expansion) was developed as a sensitive technique for the detection of low-concentration free radicals in the atmosphere. The application of FAGE to tropospheric hydroxyl (H0) and hydroperoxyl (H0₂) radicals has yielded calibrated measurements of both species in both clean air and highly polluted urban air. For HO calibration, a continuously stirred tank reactor provides a uniform external HO concentration, which can be measured by gas chromatography of an HO-reactive hydrocarbon. The aerodynamics of the air-sampling process has been modeled computationally, with results that agree with empirical observations of the effects of nozzle diameter on HO loss during sampling. The authors have also modeled airborne fluid dynamics of a FAGE probe. They have recently obtained FAGE sensitivity as high as ± 1 × 10⁶ cm-³ for a 6-minute averaging period, during field studies in highly polluted Los Angeles air, yielding a 7:1 signal-to-noise ratio near midday. Multipass excitation can further improve this sensitivity. The authors summarize their recent field studies of HO and HO², current work on improved calibration methods, other improvements, and future plans. Close

• 2. [Article] Sources and Pathways to the Environment and Environmental Presence

  In an attempt to successfully address and reduce contamination from toxic chemicals and other pollutants in the Oregon environment, the Oregon Department of Environmental Quality is in the early stages ...

  Citation × Citation Citation Abstract Copy Title: Sources and Pathways to the Environment and Environmental Presence Author: Chadil, Tess Year: 2011 In an attempt to successfully address and reduce contamination from toxic chemicals and other pollutants in the Oregon environment, the Oregon Department of Environmental Quality is in the early stages of developing a comprehensive agency-wide toxics reduction plan. The plan seeks to find a more efficient, sustainable approach to addressing contaminants of concern to human and ecological health. Team Toxics, a work group compromised of members from various DEQ departments, has been created to collaborate and create the framework for developing these strategies. In summer 2009, Team Toxics was in the very early stages of development, and found the need to gather as much information as possible about each chemical on the focus list. This project began as an internship for DEQ, to help compile research on each of the focus list chemicals, and present it in a consolidated, efficient format, that would facilitate general discussions early in the process and direct DEQ to areas that may need additional research. The goal of this project was to compile as much research as possible on each of the focus list chemicals. The information targeted in the research was data or literature describing sources that generate, use or release each chemical, the relative magnitude of those releases, and the presence of each chemical in the local environment. The data were compiled into two tables for each category: Sources and Pathways to the Environment and Environmental Presence. This standardized format provides an accessible, efficient way to assess the relative abundance of data in preparation for the development of the toxics reduction strategies for each chemical. Title: Sources and Pathways to the Environment and Environmental Presence Author: Chadil, Tess Year: 2011 In an attempt to successfully address and reduce contamination from toxic chemicals and other pollutants in the Oregon environment, the Oregon Department of Environmental Quality is in the early stages of developing a comprehensive agency-wide toxics reduction plan. The plan seeks to find a more efficient, sustainable approach to addressing contaminants of concern to human and ecological health. Team Toxics, a work group compromised of members from various DEQ departments, has been created to collaborate and create the framework for developing these strategies. In summer 2009, Team Toxics was in the very early stages of development, and found the need to gather as much information as possible about each chemical on the focus list. This project began as an internship for DEQ, to help compile research on each of the focus list chemicals, and present it in a consolidated, efficient format, that would facilitate general discussions early in the process and direct DEQ to areas that may need additional research. The goal of this project was to compile as much research as possible on each of the focus list chemicals. The information targeted in the research was data or literature describing sources that generate, use or release each chemical, the relative magnitude of those releases, and the presence of each chemical in the local environment. The data were compiled into two tables for each category: Sources and Pathways to the Environment and Environmental Presence. This standardized format provides an accessible, efficient way to assess the relative abundance of data in preparation for the development of the toxics reduction strategies for each chemical. Close

• 3. [Article] State of the River Report for Toxics

  The United States Environmental Protection Agency (EPA) strives to prevent pollution, protect water quality and improve ecosystems in order to reduce risks to human health and the environment. As outlined ...

  Citation × Citation Citation Abstract Copy Title: State of the River Report for Toxics Author: Carter, Bradley Year: 2009 The United States Environmental Protection Agency (EPA) strives to prevent pollution, protect water quality and improve ecosystems in order to reduce risks to human health and the environment. As outlined in the Agency’s Strategic Plan, the Columbia River Basin was identified as a “National Priority” and designated as one of our nation’s seven “Large Aquatic Ecosystems”. This designation grants legislative status equal to the Chesapeake Bay, Great Lakes, Gulf of Mexico, South Florida Ecosystem, Long Island Sound and Puget Sound. The Strategic Plan is the Agency’s road map of future work efforts, and targets specific goals that are expected to result in a healthier Columbia River Basin. In support of the plan, the Columbia Basin State of the River Report for Toxics (SORR) is the culmination of the collaborative efforts of the Toxics Reduction Working Group - a collection of Federal, State, and municipal agencies, Indian Tribes, non-profit groups and private industries - intended to increase public understanding about the impacts of toxics in the Basin and foster new and enhance existing partnerships to reduce toxics. The Report centers on contaminants of concern (COCs), indicators, toxicant trends, and reduction efforts. SORR will be available in print form by February, 2009. Title: State of the River Report for Toxics Author: Carter, Bradley Year: 2009 The United States Environmental Protection Agency (EPA) strives to prevent pollution, protect water quality and improve ecosystems in order to reduce risks to human health and the environment. As outlined in the Agency’s Strategic Plan, the Columbia River Basin was identified as a “National Priority” and designated as one of our nation’s seven “Large Aquatic Ecosystems”. This designation grants legislative status equal to the Chesapeake Bay, Great Lakes, Gulf of Mexico, South Florida Ecosystem, Long Island Sound and Puget Sound. The Strategic Plan is the Agency’s road map of future work efforts, and targets specific goals that are expected to result in a healthier Columbia River Basin. In support of the plan, the Columbia Basin State of the River Report for Toxics (SORR) is the culmination of the collaborative efforts of the Toxics Reduction Working Group - a collection of Federal, State, and municipal agencies, Indian Tribes, non-profit groups and private industries - intended to increase public understanding about the impacts of toxics in the Basin and foster new and enhance existing partnerships to reduce toxics. The Report centers on contaminants of concern (COCs), indicators, toxicant trends, and reduction efforts. SORR will be available in print form by February, 2009. Close

• 4. [Article] Designing More Effective Air Quality Advisories

  Background: There is increasing concern about the impact of air quality on human health in urban environments and how to best reduce impacts through public policies. An NSF Biocomplexity Project - "Feedbacks ...

  Citation × Citation Citation Abstract Copy Title: Designing More Effective Air Quality Advisories Author: Olexy, Justin Year: 2008 Background: There is increasing concern about the impact of air quality on human health in urban environments and how to best reduce impacts through public policies. An NSF Biocomplexity Project - "Feedbacks between Urban Systems and the Environment" (FUSE), led by Portland State University, studies the human feedbacks and responses to air quality and heat advisories through data collected in city-wide phone surveys in Portland, OR and Houston, TX. On days when ozone levels are predicted to exceed air quality standards, regulatory agencies issue air quality advisories which ask residents to reduce certain air polluting behaviors such as driving and lawn mowing. However, there have been very few studies of the effectiveness of these systems. Previous work documented that in both Portland and Houston, around ~10% of the population respond to voluntary advisories (Semenza et. al, 2008). In the testbed cities, the survey also asked respondents questions about their personal emissions-related behavior such as driving, mowing, use of household products, etc., as well as how that behavior was effected by an air quality advisory. Objectives: In this project, the survey data is used to accomplish three major tasks. Firstly, to estimate emissions based on the survey responses. For example, estimating VOC emissions based on reported mowing behavior (size of lawn, frequency of mowing, and type of mower). Secondly, to compare reported behavior during normal days to behavior during air advisory days. And finally, to compare the emissions estimates to demographic data (such as population density) to find any trends. For example, can variations in emission patterns be predicted using a demographic characteristic such as housing density? Currently the EPA and the Oregon DEQ estimate many types of emissions on a per capita basis. These per capita emissions numbers are generally not adjusted for any local demographic information. One additional use of this research could be to improve current emissions estimation methods. Methods: Survey responses to questions about emissions related behavior were used as activity factors in emissions calculations. The emission estimations were then tested against demographics such as housing density. For the purpose of graphical representation, housing density was broken into four quartiles to represent four different levels of density. For statistical analysis housing density was not categorized. Results: Emissions behavior, in several cases, appears to be linked to demographic features such as housing density. Per capita lawn care hydrocarbon emissions, vehicle emissions, and several consumer product category emissions trend higher towards lower housing density in both Portland and Houston. Conclusions: The results of this research project could be used to tailor air quality advisories to better target their audience with appropriate messages, thereby more effectively improving air quality during potentially hazardous air quality conditions. Understanding demographic elements to emissions estimation could be used by environmental agencies to produce better emission estimations. Title: Designing More Effective Air Quality Advisories Author: Olexy, Justin Year: 2008 Background: There is increasing concern about the impact of air quality on human health in urban environments and how to best reduce impacts through public policies. An NSF Biocomplexity Project - "Feedbacks between Urban Systems and the Environment" (FUSE), led by Portland State University, studies the human feedbacks and responses to air quality and heat advisories through data collected in city-wide phone surveys in Portland, OR and Houston, TX. On days when ozone levels are predicted to exceed air quality standards, regulatory agencies issue air quality advisories which ask residents to reduce certain air polluting behaviors such as driving and lawn mowing. However, there have been very few studies of the effectiveness of these systems. Previous work documented that in both Portland and Houston, around ~10% of the population respond to voluntary advisories (Semenza et. al, 2008). In the testbed cities, the survey also asked respondents questions about their personal emissions-related behavior such as driving, mowing, use of household products, etc., as well as how that behavior was effected by an air quality advisory. Objectives: In this project, the survey data is used to accomplish three major tasks. Firstly, to estimate emissions based on the survey responses. For example, estimating VOC emissions based on reported mowing behavior (size of lawn, frequency of mowing, and type of mower). Secondly, to compare reported behavior during normal days to behavior during air advisory days. And finally, to compare the emissions estimates to demographic data (such as population density) to find any trends. For example, can variations in emission patterns be predicted using a demographic characteristic such as housing density? Currently the EPA and the Oregon DEQ estimate many types of emissions on a per capita basis. These per capita emissions numbers are generally not adjusted for any local demographic information. One additional use of this research could be to improve current emissions estimation methods. Methods: Survey responses to questions about emissions related behavior were used as activity factors in emissions calculations. The emission estimations were then tested against demographics such as housing density. For the purpose of graphical representation, housing density was broken into four quartiles to represent four different levels of density. For statistical analysis housing density was not categorized. Results: Emissions behavior, in several cases, appears to be linked to demographic features such as housing density. Per capita lawn care hydrocarbon emissions, vehicle emissions, and several consumer product category emissions trend higher towards lower housing density in both Portland and Houston. Conclusions: The results of this research project could be used to tailor air quality advisories to better target their audience with appropriate messages, thereby more effectively improving air quality during potentially hazardous air quality conditions. Understanding demographic elements to emissions estimation could be used by environmental agencies to produce better emission estimations. Close