Tutorials Information

Abstract: Information coming soon.

Bio: Information coming soon.

Abstract: As aerosol scientists we know that many diseases such as asthma, pneumoconiosis and lung cancer are associated with human exposure to certain aerosols. These associations were provided by epidemiological studies conducted after people were exposed and/or they were elucidated by toxicology using animal models, in vitro experiments and sometimes carefully controlled human exposure studies. Since we often justify our own research by relating it to potential health outcomes, it is important for us to understand how toxicological research is done and its attributes and limitations. This tutorial will emphasize in vivo and in vitro animal models and how toxicologists identify the potential health effects of aerosols. Specific biological endpoints will be explained with an emphasis on endpoints related to oxidative stress. These endpoints and how they relate to laboratory modes of exposure, mechanisms of pathological action, and their relevance and biological significance will be discussed. Other issues that influence oxidative stress such as particle overload, deposition hot spots and particle characteristics that affect dose will be addressed. Aerosols such as carbon nanotubes, silica and diesel particulate matter will be highlighted in case studies that demonstrate many of the topics presented in this tutorial.

Bio: Maura Sheehan is a retired Professor in the Environmental Health Program at West Chester University of Pennsylvania. She has taught a variety of courses including industrial hygiene, environmental toxicology and environmental health. Maura is a Certified Industrial Hygienist, a Fellow of the AIHA and is currently developing a consulting practice. She has been a member of the AAAR since 1990 and has served as chair of the Health Related Aerosols committee. Her research has involved the generation, evaluation and control of workplace aerosols.

Abstract: Epidemiological and toxicological studies from researchers worldwide have linked human exposure to traffic-related air pollutants near roadways with a wide range of adverse health effects. Given the large population living, working, and traveling near roadways and the disproportionately high exposure by people of low income and ethnic minorities, near-road air pollution is not only a public health concern, but also an environmental justice issue. On the research side, decades’ efforts have been put into characterizing near-road air pollution via experimental and monitoring techniques, and advancements in several research fronts have been reported. On the regulatory side, a growing number of near-road air monitoring networks have been established across the country following the historical requirement for NO2 monitoring near major roads in large urban areas by EPA in 2010. The aim of this tutorial is to elucidate the scientific principles, applicability and limitations of current methods in characterizing and mitigating near-road air pollution. This tutorial will start with a brief introduction of the history of near-road air pollution, highlighting the related milestones in sciences and regulations. Then the tutorial will examine the research methods in near-road air pollution monitoring and modeling, respectively. Monitoring wise, the tutorial will go through experimental techniques in characterizing physical/chemical properties of traffic-related air pollutants near roadways and quantifying on-road emission factors. Modeling wise, various types of simulation tools that have been applied to near-road problems will be introduced and compared, including Gaussian-based models such as CALINE4, AERMOD and R-LINE, chemical transport models such as CMAQ, computational fluid dynamics (CFD) models, and geostatistical land-use regression (LUR) models. Next, brief reviews of passive mitigation strategies (e.g., alterative roadway/street configurations, solid barriers, porous barriers, green walls, and indoor infiltration) to near-road air pollution and data availability from nationwide near-road air monitoring network will be provided. The tutorial will conclude with a summary of future research needs.

Bio: Dr. Max Zhang is currently an associate professor at the School of Mechanical and Aerospace Engineering, Cornell University, and directs Energy and the Environment Research Laboratory (EERL). His research focuses on micro-environmental air quality, using numerical models and experimental techniques. Dr. Zhang received his PhD in Mechanical Engineering from University of California at Davis in 2004, and was a visiting scientist to USEPA Atmospheric Modeling Division in 2000 and 2002.

Abstract: The absence of consensus on the direct radiative forcing estimates of carbonaceous aerosol is one of the grand challenges in atmospheric climate science. A primary reason for this discrepancy is the inaccurate parameterizations of aerosol microphysical properties in current climate models. In this tutorial, I will begin with a general discussion on aerosol formation mechanisms in combustion systems and the resultant particle characteristics. This will be followed by a discussion on contemporary measurement and characterization techniques of aerosol microphysical properties. Particular emphasis will be placed on state-of-the-art computational techniques and instruments available for accurate quantification of aerosol morphologies corresponding to different mixing states, and wavelength-dependent absorption and scattering cross-sections. Finally, recent developments in the direction of identifying universal scaling relations for light absorption and scattering by internally mixed black carbon aerosol will be discussed.

Bio: Dr. Rajan Chakrabarty is an assistant professor at Washington University in St. Louis, where he has been working since 2014. He received his Ph.D. in Chemical Physics from the University of Nevada Reno in December 2008, following which he worked as an assistant research professor at the Desert Research Institute. His list of publications includes over 50 peer-reviewed papers concerning the radiative forcing of carbonaceous aerosols and nano-engineering of aerosols for energy applications. He is the recipient of several national awards including the National Science Foundation CAREER award, and the 2017 Richard M. Goody award for outstanding early career contributions to atmospheric radiation & remote sensing.

Abstract: Information coming soon.

Bio: Information coming soon.

Abstract: A number of population based epidemiological studies as well as toxicological and clinical studies indicate a strong association between ambient particulate matter (PM) exposure and adverse health outcomes. Most of the recent studies seem to be now converging on the initiating step of the PM toxicity ladder, which is the generation of reactive oxygen species (ROS). The elevated concentration of ROS above the capacity of cellular antioxidants to oxidize them leads to a state of oxidative stress, wherein excess ROS starts oxidizing important biomolecules such as DNA and proteins. Recognizing the importance of this ROS generation step in the observed toxicity of PM, a variety of probes were developed to measure the oxidative properties of ambient particles. Broadly, they can be classified into two groups – cellular and chemical (acellular). However, despite being in use for over a decade, there is huge ambiguity in the aerosol research community around the usage of term - ROS associated with ambient PM (e.g. ROS on the particle, ROS activity of the particle, oxidative potential, etc.) and their measurements. We target to remove some of this ambiguity in the tutorial. We will first start with the basic definitions of ROS, ROS activity, oxidants, and oxidative potential. Next, we will describe various methods to measure these species/properties. Here, we will also discuss the recently built automated and online instruments to measure the particle-bound ROS, oxidative potential and ROS activity of the ambient PM. And, finally, we will present the results from numerous studies, including from our own investigations, showing the biological relevance of measuring these properties of the ambient particles.

Bio: Dr. Verma is an assistant professor at the University of Illinois Urbana Champaign and his current work is focused on measuring the toxicological properties of ambient air pollutants, investigating their emission sources and linkages with the observed health effects. In his 9 years of research career, he has published 25 peer-reviewed articles in highly ranked journals and has presented his work in more than 30 various seminars/meetings and conferences, including several invited talks. He is the current vice president of the Health related Aerosol working group at AAAR and has earned numerous awards and recognitions for his work including the invited chair for special symposium/sessions on Air Pollution and Health in the annual AAAR conferences (2014, 2015 and 2017).

Abstract: Water is the most abundant condensed-phase species in the atmosphere. Chemistry in atmospheric waters can sometimes be faster (e.g., sulfur oxidation), lead to different products (e.g., glyoxal oxidation) or lead to different particle size distributions than gas phase chemistry. This tutorial examines atmospheric evidence for aqueous organic chemistry, types of chemistry and differences between chemistry in clouds and wet aerosols, progress understanding constraints, key unanswered questions, challenges and resources.

Bio: Barbara Turpin is Department Chair and Professor of Environmental Sciences and Engineering at University of North Carolina (UNC) at Chapel Hill. She combines laboratory experiments, chemical modeling and field research to improve the understanding of linkages between air pollution emissions and human exposures. Research interests include secondary organic aerosol formation through aqueous chemistry (e.g., cloud processing) and indoor chemistry. She is a Fellow of the American Association for the Advancement of Science, the American Geophysical Union and the American Association for Aerosol Research (AAAR). She is a recipient of AAAR’s Sinclair Award. Professor Turpin is a Past President of the American Association for Aerosol Research (AAAR) and an editor of Environmental Science and Technology (ES&T).

Abstract: The allure of low-cost AQ sensor technologies to inform (and transform) our daily interactions with the air we breathe has lead to a rapid increase in their availability across multiple sectors of the consumer market. From DIY entrepreneurs to large multi-national corporations, AQ sensors are the core selling point of many connected devices. In contrast to the traditional (research-first) development of pollutant measurement technologies, research efforts focused on understanding sensor response and quantification have lagged public adoption. In this context, it is increasingly important that the atmospheric, aerosol science research community contribute to the rapidly evolving field of air quality sensors. This tutorial will present empirically-based assessments of low-cost AQ sensors across realistic environmental sampling domains. The tutorial will primarily focus on electrolytic (gas-phase species) sensors but will also include a discussion of current state-of-knowledge regarding low cost optical (particulate matter) sensors. The tutorial will provide background descriptions of sensor hardware/design followed by detailed discussion of results obtained from laboratory and field-based calibration experiments.

Bio: Eben S. Cross is a Senior Scientist at Aerodyne Research, Inc., working with the Center for Aerosol and Cloud Chemistry. He also holds a Research Scientist affiliation with the Department of Civil and Environmental Engineering at the Massachusetts Institute of Technology. He earned his bachelor's degree in Environmental Chemistry from Connecticut College ('03) and Ph.D. in Physical Chemistry from Boston College ('08). Much of Dr. Cross' research has focused on instrument development, utilizing mass spectrometry to explore real-time emission characteristics from combustion sources (aircraft, diesel, cookstoves). More recently, Dr. Cross has shifted his focus toward air quality sensors; teaching a senior capstone course on smart cities at MIT, deploying pilot-scale AQ sensor networks in Cambridge and Dorchester, MA, and leading a research effort (ARISense) at Aerodyne focused on the development of integrated low-cost AQ sensor systems.

Abstract: This tutorial will enable participants to get an "under the hood" look at a broad spectrum of currently available aerosol instruments. Whether you are an experimentalist, modeler, or both, this is an opportunity to learn how fundamental aerosol scientific principles are used in actual aerosol measurement technologies. Key capabilities, as well as limitations, of each technique will be described in order to instill a better appreciation of what different instruments can and cannot, do. In each of two separate sessions, five or six aerosol instrumentation suppliers will present the design, concepts, and engineering choices that led to the successful development of different aerosol instrumentation. The tutorial is not a marketing and sales opportunity for participating vendors; this is an education session with an emphasis entirely on technology and the key physical concepts employed by the instrumentation. A primary goal is that by the end of the tutorial participants no longer consider instrumentation a "black box" but rather have some understanding of the principles and design consideration that went into the development of the various instruments. A secondary goal is that participants will use the information presented on measurement uncertainties and limitations to better avoid over-interpreting measurement results.

Aerosol Devices Inc. — Spot Sampler and the MAGIC CPC

AethLabs — microAeth® MA200 multi-wavelength Black Carbon Monitor

Brechtel — Tricolor Absorption Photometer (TAP) and STAP

Kanomax — Drift Tube Ion Mobility Spectrometer

Magee Scientific — Total Carbon Analyzer

URG Corporation —Ambient Ion Monitor

Abstract: Chemical transport models (CTMs) are numerical simulations representing the interplay of emissions, chemistry, transport, microphysics, and deposition that determine the behavior of atmospheric aerosols. As research tools, they play several important roles: assessing the significance of newly discovered or hypothesized processes in an atmospheric context, testing our knowledge of aerosol behavior against ambient observations, and predicting the impacts of policy decisions. Conceptually, they are simple mass and population balances. Complexity arises from several factors: the chemical and physical interactions of many dozen species; transport across a three-dimensional grid representing an urban airshed, a geographic region or even the entire globe; and the numerical approximations required to solve the resulting equations efficiently. This tutorial will provide an overview of the essential components of CTMs, surveying the major algorithms for representing aerosol emissions, chemistry, microphysics, phase partitioning, transport, and deposition. Special focus will be paid to numerical algorithms for representing aerosol size distributions and their evolution via the microphysical processes of condensation, coagulation, and nucleation.

Bio: Peter J. Adams is a professor at Carnegie Mellon University with a joint appointment between the Department of Civil and Environmental Engineering and the Department of Engineering and Public Policy. He earned his bachelor's degree in chemical engineering from Cornell University, followed by a master's and then PhD in chemical engineering at the California Institute of Technology. His research interests include aerosol-climate interactions, global and regional aerosol modeling and the development of aerosol microphysical simulations in climate models. Dr. Adams received the Sheldon K. Friedlander Award in 2004 from AAAR.

Abstract: Secondary aerosol is an important component of atmospheric fine particles that generally consists of organics, sulfates, and nitrates. The processes that lead to the formation of this material are often complex, and can involve gas and particle phase chemistry, nucleation, and gas-particle partitioning. In this course I will discuss the major chemical reactions and partitioning processes involved in the formation of secondary organic and inorganic aerosol (with a strong emphasis on organic aerosol) using examples from laboratory and field studies.

Bio: Paul Ziemann is a Professor in the Department of Chemistry & Biochemistry and a Fellow in the Cooperative Institute for Research in Environmental Sciences at the University of Colorado-Boulder. He received a doctorate in Chemistry from Penn State University and was a postdoctoral researcher in the Particle Technology Laboratory at the University of Minnesota. His research interests include laboratory studies of the kinetics, products, and mechanisms of organic oxidation reactions and their effects on the composition of gases, particles, and surfaces in outdoor and indoor air. He was a recipient of the AAAR Whitby Award in 2001 and served as President of AAAR from 2009–2010.
Email: paul.ziemann@colorado.edu
Phone: 303-492-9654

Abstract: Air pollution is a serious public health concern with local and global implications. Sometimes the effects of air pollution are distinct, and the causative pollutants can be easily identified and subsequently reduced. In many large cities, however, the cause-and-effect relationship is more problematic due to the type of ambient exposure. These atmospheres consist of gases and particulate matter (PM) that have undergone dynamic changes in their composition through oxidation chemistry that likely affects their overall toxicity. Thus, current research efforts focused on understanding the public health implications of exposure to these mixtures will need in vitro exposure technologies with the sensitivity and throughput at ambient concentrations to keep pace with compositional changes. In this tutorial you will learn about various in vitro exposure technologies developed by researchers at UNC-Chapel Hill and the U.S. Environmental Protection Agency to address these specific needs. The tutorial will provide detailed explanations of various technologies being used by UNC and EPA researchers and will also feature results from the first ever exposure system comparison study of many in vitro exposure technologies.

Conventional in vitro dosing methods and systems are not adequate to expose cultured cells in a manner that mimics a more realistic cell exposure at ambient levels or in a complex mixture (gases, vapors, and aerosols). Exposing cells at the air-liquid interface (ALI) has been used to better represent direct pollutant-to-cell interaction and can be reasonably regarded as an effective in vitro surrogate for inhalation. The novel instrument designed at UNC uses electrostatic charging to efficiently and uniformly deposit the particles directly onto cells at ALI conditions. The electrostatic charging has been shown not to induce adverse effects on cultured cells under specific operational conditions. While working under biological constraints, the process of collecting and depositing particles onto the cells for toxicological measurements remains highly effective. EPA has developed a suite of Cell Culture Exposure Systems (CCES) that permits the use of multi-well plates within the systems, thus minimizing handling and transferring of membrane inserts. Thermophoresis has been incorporated into one of the CCES to enhance particle deposition efficiency during exposure. These in vitro technologies can be used, in conjunction with chemical characterization instruments, to identify the specific composition of an ambient mixture to determine what is most relevant to overall toxicity. The identification and toxicity profiling of ambient pollutant mixtures is essential to support public health and assist in development of Adverse Outcome Pathways (AOPs).

[Abstract does not reflect policies of the EPA.]

Bio: William Vizuete, MS, PhD, is an associate professor in the Department of Environmental Sciences and Engineering in the Gillings School of Global Public Health. The focus of his research is atmospheric chemistry and its link to the formation of air pollution and impacts on public health. Dr. Vizuete has served as the scientific advisor for the projects leading to the direct development and testing of the in vitro technologies being showcased in the tutorial. Further, I was PI of a recently completed field campaign where lung cells were deployed in the Houston ship channel for in vitro exposures.

Bio: Dr. Zavala received a B.S in mechanical engineering from the University of California, Davis, in 2009. He conducted undergraduate research at UC Davis under the supervision of Drs. Michael Kleeman and Christopher Cappa, and at UCLA under the supervision of Dr. William Hinds. Dr. Zavala received his PhD from the Department of Environmental Sciences and Engineering in 2014 under the direction of Drs. Harvey Jeffries and Kenneth Sexton. His dissertation focused on the development of an electrostatic air sampler as an alternative method for aerosol in vitro exposure studies. Currently, he is an ORISE Postdoctoral Research Fellow at the US EPA conducting in vitro exposure studies to air-pollutant mixtures under the supervision of Drs. David DeMarini, Ian Gilmour, and Mark Higuchi.

Bio: Mark A. Higuchi, MSc, PhD, received his doctorate in Engineering Management from California Coast University, Santa Ana in 2004; Masters in Toxicology from North Carolina State University, Raleigh in 1985; and BS in Environmental Chemistry from Long Island University, Southampton College, NY in 1982. Dr. Higuchi has worked in the field of inhalation toxicology and engineering for over 30 years in which he designed and developed numerous novel in-vitro and in-vivo exposure systems for the conduct of inhalation toxicology studies. In his career, he has lead inhalation toxicology research teams within industry, contract research organizations, and government research laboratories. He provides expertise, mentoring, and training in the field of inhalation toxicology. Since 2010, he has been Branch Chief of the Inhalation Toxicology Facilities within the Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development at the U.S. EPA in RTP, NC.

Abstract: This tutorial will enable participants to get an "under the hood" look at a broad spectrum of currently available aerosol instruments. Whether you are an experimentalist, modeler, or both, this is an opportunity to learn how fundamental aerosol scientific principles are used in actual aerosol measurement technologies. Key capabilities, as well as limitations, of each technique will be described in order to instill a better appreciation of what different instruments can and cannot, do. In each of two separate sessions, five or six aerosol instrumentation suppliers will present the design, concepts, and engineering choices that led to the successful development of different aerosol instrumentation. The tutorial is not a marketing and sales opportunity for participating vendors; this is an education session with an emphasis entirely on technology and the key physical concepts employed by the instrumentation. A primary goal is that by the end of the tutorial participants no longer consider instrumentation a "black box" but rather have some understanding of the principles and design consideration that went into the development of the various instruments. A secondary goal is that participants will use the information presented on measurement uncertainties and limitations to better avoid over-interpreting measurement results.

Cambustion — Aerodynamic Aerosol Classifier (AAC)

Dekati Ltd. — High Resolution ELPI+

Droplet Measurement Technologies — WIBS-NEO

Grimm Technologies Inc. — Mini-WRAS (Wide Range Aerosol Spectrometer))

Palas GmbH — U-SMPS

TSI Inc. — CPCs, efficient local and remote use

Abstract: This tutorial will have four main sections:

1. A review of both dynamical and equilibrium behavior of organic aerosol;
2. The design, implementation, and potential pitfalls of both chamber and flow-tube experiments;
3. The analysis of SOA formation data;
4. Parameterizations used in various chemical transport models.

First we shall discuss what drives organic vapors to condense to particles and how the dynamics and equilibrium change with conditions (composition, water content, temperature, etc). Second, we shall apply those theoretical considerations to experimental design, both for an idealized experiment and for real-world situations. We shall discuss issues including equilibrium timescales and wall losses. Third, we shall discuss methods for interpreting SOA production data, including inversion (fitting) to equilibrium models with either unknown or specified volatility (multi-product models and the volatility basis set) as well as forward comparison between measurements and models using chamber box models. Finally, we shall discuss various parameterizations used to represent SOA formation in chemical transport models, considering the relative advantages and disadvantages of each.

Bio: Neil M. Donahue is the Thomas Lord Professor of Chemistry in the Departments of Chemistry, Chemical Engineering and Engineering and Public Policy at Carnegie Mellon University, where he is also Director of the Steinbrenner Institute for Environmental Education and Research. He has an AB in Physics from Brown University and a PhD in Meteorology from MIT. He has studied the origin, behavior, and fate of atmospheric organic compounds for the past 30 years from many different perspectives. These include in-situ measurement, modeling, theory, and laboratory experiments ranging from elementary gas-phase kinetics and mechanisms to probing the evolution of complex organic mixtures subject to photochemistry. He is the author of more than 220 publications, many of which are highly cited.

Abstract: This tutorial will address the role of chemistry in setting the chemical character of indoor environments, contrasting the behavior prevalent indoors to that which occurs outdoors. Indeed, one of the central questions in the field is whether the chemical character indoors is dominated by species transported in from outdoors, via rapid air exchange. Or, are there sources of gases and particles indoors that dominate over the outdoor signal? Attention in the tutorial will be given to indoor oxidants and the chemistry they may promote. As well, the indoor environment is characterized by very high surface area-to-volume ratios that enhance the importance of multiphase chemistry and partitioning of semivolatile and involatile species. The indoor environment contains highly spatially and temporally heterogeneous sources – arising from combustion, humans, cleaning processes, etc; the chemical character of these sources and the chemistry they may drive will be discussed. Finally, the application of novel analytical methods to the measurement of the chemical nature of the indoor environment will be described.

Bio: Jon Abbatt is a professor in the Department of Chemistry at University of Toronto. He has worked in the atmospheric chemistry field for over 30 years - at Harvard (PhD), MIT (postdoc), U of Chicago (assistant/associate professor) and Toronto. His current research interests lie in three general directions. He is the principal investigator for a large Canadian research network (NETCARE) that is addressing the sources, fate and impacts of aerosol particles in remote environments, especially the Arctic. As well, he has long maintained an active laboratory research program in atmospheric aerosol multiphase chemistry. His most recent research direction has been into the field of indoor chemistry, where he is using a number of the tools and concepts developed to address issues of importance to outdoor atmospheric chemistry to study the indoor environment.

Abstract: Oxidation is a fundamental atmospheric process, in which emissions of mostly reduced species are transformed into more oxygenated ones, sometimes increasing aerosol mass and/or number in the process. Oxidation can be studied using different types of reactors, of which large environmental chambers have been the dominant one until recently. Oxidation flow reactors (OFR) have seen greatly increased use in the last decade, especially within the aerosol field, and have recently been commercialized. The Potential Aerosol Mass (PAM) reactor is one popular type, but several other custom reactor designs are in use. In this tutorial I will review common reactor designs, with special focus on OFRs that generate OH from low-pressure mercury lamps. The radical chemistry will be described, and best practices of OFR operation to avoid non-atmospheric results will be reviewed. The current options for performing low-NO vs. high-NO oxidation of VOCs will be reviewed. Techniques for quantification of OFR results, as well as some knowledge gaps and ideas for future research will be summarized. Background information on OFRs can be found at https://sites.google.com/site/pamwiki/

Bio: Jose-Luis Jimenez is a Professor of Chemistry and Fellow of CIRES at the University of Colorado-Boulder. Dr. Jimenez received his PhD in 1999 from MIT, and was a postdoc at Aerodyne and Caltech. He was one of the co-developers of the Aerodyne Aerosol Mass Spectrometer (AMS). He is an author of over 300 publications, a Fellow of the AAAR and AGU, and an ISI Highly Cited Scientist. His group has performed extensive experimental and modeling research on OFRs, in particular pioneering OFR application to the oxidation of ambient air and aircraft studies and the detailed simulation of radical chemistry. For more information see http://cires1.colorado.edu/jimenez/