<p dir="ltr">The goal of this thesis is to develop a method of evaluating long-term IAQ performance of an industrial facility and use machine-learning to model the relationship between critical air pollutants and the facility’s HVAC systems and processes. The facility under study for this thesis is an electroplating manufacturer. The air pollutants at this facility that were studied were particulate matter, total-volatile organic compounds, and carbon-dioxide. Upon sensor installation, seven “zones” were identified to isolate areas of the plant for measurement and analysis. A statistical review of the long-term data highlighted how this facility performed in terms of compliance. Their gaseous pollutants were well within regulation. Particulate matter, however, was found to be a pressing issue. PM10 was outside of compliance more than 15% of the time in five out of seven of the zones of study. Some zones were out of compliance up to 80% of the total collection period. The six pollutants that met these criteria were deemed critical and moved on to machine learning modeling. Our model of best fit for each pollutant used a gaussian process regression model, which fits best for non-linear rightly skewed datasets. The performance of each of our models was deemed significant. Every model had at least a regression coefficient of 0.935 and above for both validation and testing. The maximum average error was 12.64 ug.m^3, which is less than 10% of the average PM10 concentration. Through our modeling, we were able to study how HVAC and production played a role in particulate matter presence for each zone. Exhaust systems of the west side of the plant were found to be insufficient at removing particulates from their facility. Overall, the methods developed in this thesis project were able to meet the goal of analyzing IAQ compliance, modeling critical pollutants using machine learning, and identifying a relationship between these pollutants and an industrial facility’s HVAC and production systems.</p>

Master of Arts / Department of Geography / Douglas G. Goodin / My thesis characterizes the temporal and spatial behavior of ozone and fine particulate matter in the Kansas City metropolitan area. I also investigate the capability of a synoptic weather typing scheme, the Spatial Synoptic Classification, to characterize and explain the behavior of ozone and fine particulate matter in the Kansas City area. Daily maximum ozone concentrations from nine active ozone monitoring stations and daily average particulate concentrations six active PM2.5 monitoring stations were compared to daily SSC weather type records from 2004-2010. Analysis of Variance (ANOVA) tests were conducted on the ozone and PM2.5 data to analyze temporal and spatial behavior. A non-parametric recursive partitioning technique was used to create a conditional inference tree-based regression model to analyze the association between the different SSC weather types and the selected pollutants. The ANOVA results showed significant seasonal trends with both pollutants. In general, ozone concentrations are typically lower in the spring and autumn months and higher during the summer months. PM2.5 concentrations were not as dependent on the season, however, they did tend to be higher in the late summer months and lower in the autumn months. The results also showed significant differences for both pollutants in average concentration depending on location. The ozone concentrations generally tended to be higher in the areas that are located downwind of Kansas City and lowest at the station located in the middle of the urban area. Fine particulates also seemed to be highest in the downwind portion of the urban area and lowest in the region upwind of the city. The conditional inference tree showed that higher concentrations of both pollutants are associated with tropical air masses and lower concentrations are associated with polar air masses.

Call number: LD2668 .T4 1984 T78 / Master of Science

Published Article / Air pollution, just like any other type of pollution, produces harmful effects to man and his environment. In spite of knowing this, many less industrialised countries of the world have no air quality monitoring strategies in place. Consequently, documented evidence of air pollution studies in such countries is scarce. This is the case in Tanzania. This scenario is made worse by lack of scientific tools which could aid in identifying air pollution-prone areas with a view to aiding town planners in locating safe sites for schools, hospitals and residential areas as well as parks. In this paper, we present results of a study carried out in the city of Dar-es-Salaam, Tanzania on air pollution in residential areas. Results show significant air pollution in the studied areas. Moreover, both adults and children are at risk due to lead pollution in the air.

This thesis develops, tests and applies methods for space-time modelling of exposure to air pollution using GIS. This involves linkage of five main sub-models: a traffic model, a model of urban air pollution - combining local and ‘background’ pollution models - a network analysis tool for modelling exposure during journeys, and a time-activity model. The model can provide exposure estimates for individuals or population groups. The study took place entirely within Northampton, UK. The model used to estimate hourly PM10 concentrations at outdoor locations gave a moderate fit to monitored data. Results were shown to be comparable with the best results from other studies. This research also found a strong, linear relationship between concentrations of PM10 during simultaneous monitoring of walking and in-car concentrations. This relationship was used to calibrate modelled outdoor pollution levels to give in-car concentrations. Modelled journey- time exposures for walking performed equally with predictions made using a fixed- site monitor located close to journey routes. The model did not perform as well as the fixed-site monitor in predicting in-car exposures. The application of the model to a walk-to-school policy, in which modelled local traffic levels were reduced by 20%, demonstrated that the benefits of the reduction were not spread evenly across a sample of schoolchildren, but varied depending on the route used to school and the location of homes and schools. For those switching between car and walk there may be positive or negative effects of the policy in terms of savings in average hourly exposures, depending on their specific journey and time activity patterns. The results from this research showed that, although the model worked reasonably well in estimating exposures, a number of improvements are needed. These include better models of background concentrations, more detailed models of in-car conditions, and extending exposure modelling to include dose-response estimates

Exposure to air pollution, particularly fine and ultrafine particulate matter derived from combustion sources, has been consistently associated with increased cardiovascular morbidity and mortality. Recent controlled exposure studies demonstrate that short-term exposure to diesel exhaust, which can contribute up to 40% of urban particulate air pollution, results in impaired vascular endothelial and fibrinolytic function in healthy volunteers, and increased exercise-induced myocardial ischaemia in patients with coronary heart disease. These observations may, in part, explain the observed increase in cardiovascular events following exposure to air pollution. Despite these observations there remain uncertainties regarding the key constituents of the air pollution mixture that mediate these adverse effects, and the underlying physiological and biological pathways involved. In these studies, using two controlled exposure facilities, I explored the vascular effects of the most prevalent gaseous component of the air pollution mixture – nitrogen dioxide – and the mechanisms responsible for impaired vasomotor function following exposure to diesel exhaust. Furthermore, I investigated the effect of acute exposure to “real-world” urban air pollution in both healthy volunteers and patients with coronary heart disease, and the effect of reducing that exposure using a simple facemask. In total, 10 healthy volunteers were exposed to nitrogen dioxide, and 29 healthy volunteers exposed to dilute diesel exhaust in a series of doubleblind randomised crossover studies. Exposure to nitrogen dioxide had no effect on either vasomotor function or endogenous fibrinolysis, providing indirect evidence that the adverse vascular effects are predominantly driven by particulate components. Following exposure to diesel exhaust there was no up regulation of endothelin-1 production, although there was increased vasoconstriction to intra-arterial infusion of endothelin-1. Following endothelin A receptor antagonism, there was attenuated vasodilatation following exposure to diesel exhaust as compared to air, an effect abrogated by endothelin B receptor antagonism. My findings suggest that the endothelin system does not play a central role in the adverse vascular effects of air pollution, but given the tonic interaction between the endothelin and nitric oxide systems, these observations could be explained by reduced nitric oxide bioavailability. Following diesel exhaust inhalation, plasma nitrite concentrations (as a marker for nitric oxide generation) are markedly increased without changes in haemodynamics or basal blood flow consistent with increased nitric oxide consumption. In the presence of a nitric oxide clamp, and without endogenous nitric oxide release, the vascular responses to vasodilators are similar. This perturbation of nitric oxide consumption and release appears to underlie the observed vascular endothelial effects. Fifteen healthy volunteers and 98 patients with coronary artery disease were recruited in Beijing, China. Subjects walked along a predefined city centre route for 2 hours in the presence and absence of a highly efficient facemask to reduce personal particulate air pollution exposure in an open label randomised crossover study. When wearing a facemask, there was an attenuation of exercise-induced increases in blood pressure, an improvement in heart rate variability, reduced myocardial ischaemia and subjects reported fewer symptoms. My findings have identified the biological mechanisms underlying the adverse vascular effects of exposure to diesel exhaust, and have helped to clarify the components responsible for these effects. Moreover, I have identified important benefits of reducing personal exposure to particulate matter using a simple facemask that have the potential to reduce cardiovascular events in patients living in urban or industrialised areas. Ongoing research in this area will provide further insight into the underlying vascular mechanisms, and the potential benefits of reducing particulate air pollution exposure, and may result in important targeted interventions to reduce the impact of air pollution on cardiovascular health.

INTRODUCTION: Airway inflammatory response is widely believed to be a central mechanism in the development of adverse health effects related to air pollution exposure. Increased ventilation and inspiratory flow rates due to physical activity in the presence of air pollution will increase the inhaled dose of air pollutants. However, physical activity can also affect lung function and may moderate the relationship between air pollution and lung function. The mechanisms that underpin the complex interplay between air pollution, physical activity, and lung function may be more sensitive to the inhaled dose of air pollution than to ambient air pollution exposure alone. Despite this, the majority of literature on the topic measures only the ambient concentration of air pollution. AIM: This study aims to characterize the relationship between inhaled air pollution dose, physical activity, and respiratory response markers of lung function, oxidative stress and inflammation among healthy adolescents. Respiratory response measures include exhaled nitric oxide (eNO), percent oxidized exhaled breath condensate glutathione (%GSSG), percent oxidized exhaled breath condensate cysteine (%CYSS), the percentage of total oxidized compounds (%Oxidized), and changes in pulmonary function, namely, forced vital capacity (FVC), forced expiratory volume (FEV1), and forced expiratory flow (FEF25-75). Air pollution measures include cumulative inhaled doses of fine particulate matter (PM2.5), ozone (O3), black carbon (BC), and particle number total (PNT). METHODS: Using a non-probability sample of high school athletes, outcomes were measured prior to and after participation in extracurricular sports practice. The inhaled dose of air pollutants during the sports practice was estimated for each participant using a novel method developed by Dr. Roby Greenwald. This observational study estimates the association between air pollution dose and outcome measures using general linear mixed models with an unstructured covariance structure and a random intercept for subject to account for repeated measures within subjects. All data analysis was completed using SAS. RESULTS: A one IQR (i.e. 345.64 µg) increase in O3 inhaled dose is associated with a 29.16% average decrease from baseline in %Oxidized. A one IQR (i.e. 2.368E+10 particle) increase in PNT inhaled dose is associated with an average decrease in FEF25-75 of 0.168 L/second from baseline. The relationship between PNT inhaled dose and eNO is moderated by activity level, with increasing activity levels attenuating the relationship. Similarly, the relationship between O3 inhaled dose and %CYSS is attenuated by activity level, with increasing activity levels corresponding to smaller changes from baseline for a constant O3 inhaled dose. DISCUSSION: Someone who inhales a high cumulative dose despite a low activity level is likely breathing in a higher concentration of air pollution in a shorter period of time than a person who receives the same dose with a high activity level. The moderating effects of activity level suggest that peaks of high concentration doses of air pollution may overwhelm cells’ endogenous redox balance resulting in increased airway inflammation. Further research that examines the relationships between dose peaks over time and inflammation could help to determine whether a high concentration dose over a short period of time has a different effect than a lower concentration dose over a longer period of time.

published_or_final_version / Radioisotope / Doctoral / Doctor of Philosophy

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management