Providing insight into relationships between air pollutant exposure and emissions using advanced modeling approaches

The Computational Atmospheric Chemistry and Exposure Group, led by Dr. Kristina Wagstrom, specializes in applying computational engineering-based approaches to address problems related to air pollution and atmospheric chemistry. The work that will be presented here uses the Particulate Matter Source Apportionment Technology (PSAT) within a state-of-the-science regional chemical transport model to provide insight into the impacts of different emissions by comparing intake fractions over a variety of conditions. Chemical transport models allow researchers and policymakers to estimate spatially and temporally resolved air pollutant concentrations over a large region (from a single city to the entire globe) by explicitly accounting for the impact of gaseous reactions, particle dynamics, transport, meteorology, emissions, removal, and aqueous chemistry. The biggest advantage of these models is that they can be used to address questions and scenarios that cannot be addressed using experimental or monitoring data. Intake fraction is simply a measure of what fraction of an emitted pollutant is ultimate inhaled by someone in the population. Estimating the inhalation intake fraction for emissions from a variety of sources provides a means by which to determine the relative impact between different emissions sources and can aide in developing efficient pollution control policies. For instance, it is likely that emissions from an elevated stack will have a lower intake fraction than ground-level emissions. In this study, we compare the ground level concentration contributions and inhalation fraction for different heights of point source emissions to those estimated using dispersion modeling approaches. We also use intake fraction as a metric by which to understand how exposure varies as you move away from an emission source region (specifically nine different cities). In addition to estimating intake fraction of primary pollutants, as is common, we also provide estimates of the intake fraction for secondary pollutants. The intake fraction for secondary pollutants is calculated based on the commonality between the precursor and product. For instance, the intake fraction of SO2 and particulate sulfate would actually be calculated as the intake fraction of the sulfur atom treating SO2-sulfate as a complete system. This approach can also be applied to the NOx-nitrate system, the ammonia-ammonium system, and similar systems of organic species. This approach provides a more thorough and complete estimation of what fraction of the original emissions are eventually inhaled by the human population, particularly as research has continued to demonstrate the importance of these secondary species to human health impacts

Shedding of porcine reproductive and respiratory syndrome (PRRS) virus in mammary secrections of sows

This thesis contains a review of the immune components in porcine mammary secretions. The review includes a discussion of the mammary gland immune system including the specific immune cell types found, and their location, within the mammary gland. This is followed by an overview of the source, quantity and function of immunoglobulins found in swine mammary secretions. The cellular components of milk and colostrum are reviewed, and their possible role in the active immune response of the neonate is discussed. Additionally the presence of non-specific immune components in mammary secretions and their functions are reviewed. Specific research exploring the potential shedding of porcine reproductive and respiratory syndrome virus (PRRSV) in mammary secretions is presented. In this study naïve gilts challenged with PRRSV late in gestation shed virus in their mammary secretions. PRRSV was demonstrated both in the cellular portion of their secretions as well as the whey. Antibody in the whey did not appear to prevent shedding of the virus. These same animals challenged in a subsequent gestation did not shed PRRSV in their mammary secretions. Additionally, sows in commercial herds that were either vaccinated or previously exposed to PRRSV, did not shed PRRS virus in their milk

Household Income and Air Pollution at Public Schools in the United States

Poor air quality at schools may negatively impact students’ academic performance.1 2 3 In this study we look at the relationship between ambient, outdoor air quality and student socioeconomic status at United States public schools. We used free and reduced lunch eligibility, as part of the USDA’s National School Lunch Program, as an indicator of household income. We focus on nitrogen dioxide (NO2), ozone (O3), and particulate matter smaller than 2.5 microns (PM2.5). We used ambient pollutant concentration estimates at census block group resolution (Kim et al.) as the outdoor air pollution concentration at each school.4 We found a positive correlation between lower socioeconomic status and higher levels of ambient air pollution. We found that on average, NO2 concentrations are 1.8 - 3.1 ppb higher (22-42%, � \u3c .001) for students in the lowest SES quartile than the highest. The concentration of PM2.5 is 0.7 - 1.2 µg/m3 higher (7-13%, � \u3c .001) for students in the lowest SES quartile than the highest. At elementary and high schools, average O3 concentrations are 0.5 ppb lower (1%, � \u3c .001) for students in the lowest SES quartile than the highest. At middle schools there is no significant difference (� \u3e 0.1) in O3 concentration between the lowest and highest SES quartiles. Atkinson Index values are highest for NO2 (0.15 - 0.17, �=1). Values for PM2.5 are one order of magnitude lower (.04, �=1) and two orders of magnitude lower for O3 (.009, �=1)

Quantifying Air Pollution at the Stamford Transportation Center

There is a need to analyze particulate matter concentrations at the Stamford Transportation Center according to the Western Connecticut Coalition of Governments. Stamford has recently undergone rapid urbanization and large scale construction resulting in traffic congestion. Congested traffic areas in urban centers are key contributors to poor air quality. Therefore, there is a need to analyze the pollution concentrations at the bus stops near the station. Every day, hundreds of shuttles and cars idle around the Transportation Center. Thousands of passengers wait at nearby bus stops every day and can potentially be exposed to high amounts of vehicle produced pollution due to their close proximity to the road. In order to collect data, the monitor will be deployed for a two week period each season and then retrieved to analyze its data. The objective of this study is to determine the relative airborne particulate matter concentrations at the Stamford Transportation Center and compare this data to the surrounding area. It was found that the winter run had the highest particulate matter concentration readings, but overall, the average readings at the Stamford Transportation Center are lower than or very close to the surrounding area

Take care - use antibiotics responsibly producter education program

Antimicrobial use in animal production has been a topic of concern with public health, animal health, and consumer advocacy groups