No description available.

Fine particulate matter (PM2.5) constitutes a significant component of ambient air pollution that has been implicated in the pathogenesis of metabolic disorders, including insulin resistance and type 2 diabetes. Among PM2.5 constituents, diesel exhaust particles (DEP) are prevalent particulates that infiltrate the bloodstream to drive systemic pathologies. The purpose of this study was to characterize the metabolic response of adipose tissue to DEP. We aimed to provide a comprehensive understanding by exploring mitochondrial bioenergetics, characterizing the inflammatory marker profile, including adipokines, and conducting a detailed histological analysis of adipocytes to provide valuable insights to the evolving understanding of the intricate interplay between pollution and adipose tissue function. Following daily inhalation exposure to DEP in mice, we observed a selective increase in adipose tissue mass and altered mitochondrial respiration in the adipose tissue. Furthermore, we observed increased pro-inflammatory cytokines, changes in adipokine secretion, and alterations in adipose histology reflective of adipocyte hypertrophy. In conclusion, exposure to DEP disrupts adipose tissue function by altering adipocyte mitochondrial function and contributing to inflammation. These novel findings provide valuable insights that may facilitate the development of therapeutic interventions addressing metabolic disorders in the future.

Diesel particulate matter (DPM) is the solid portion of diesel exhaust, which occurs primarily in the submicron range. It is complex in nature, occuring in clusters and agglomerated chains, and with variable composition depending on engine operating conditions, fuel type, equipment maintenance, etc. DPM is an occupational health hazard that has been associated with lung cancer risks and other respiratory issues. Underground miners have some of the highest exposures to DPM, due to work in confined spaces with diesel powered equipment. Large-opening mines present particular concerns because sufficient ventilation is very challenging. In such environments, reliable DPM sampling and monitoring is critical to protecting miner health. Though complex, DPM is made up primarily of elemental (EC) and organic carbon (OC), which can be summed to obtain total carbon (TC). The Mine Safety and Health Administration (MSHA) currently limits personal DPM exposures in metal/non-metal mines to 160 µg/m3 TC on an 8-hour time weighted average. To demonstrate compliance, exposures are monitored by collecting filter samples, which are sent to an outside lab and analyzed using the NIOSH 5040 Standard Method. To support real-time results, and thus more timely decision making, the Airtec handheld DPM monitor was developed. It measures EC, which is generally well correlated with TC, using a laser absorption technique as DPM accumulates on a filter sample. Though intended as a personal monitor, the Airtec has application as an engineering tool. A field study is reported here which demonstrated the usefulness of the Airtec in tracking temporal and spatial trends in DPM. An approach to sensitizing the monitor to allow "spot checking" was also demonstrated. Since DPM in mine environments generally occurs with other airborne particulates, namely dust generated during the mining process, DPM sampling must be done with consideration for analytical interferences. A common approach to dealing with mineral dust interferences is to use size selectors in the sampling train to separate DPM from dust; these devices are generally effective because DPM and dust largely occur in different size ranges. An impactor-type device (DPMI) is currently the industry standard for DPM sampling, but it is designed as a consumable device. Particularly for continuous monitoring applications, the sharp cut cyclone (SCC) has been suggested as a favorable alternative. In another field study reported here, the effect of aging (i.e., loading as an artifact of sampling) on the DPMI and SCC was investigated. Results suggest the effective cut size of the DPMI will be reduced much more rapidly than that of the SCC with aging — though even in a relatively high dust, high DPM environment, the DPMI performs adequately. In a third field study, the possibility of attachment between DPM and respirable dust particles was investigated. Such a phenomenon may have implications for both reliable sampling and health outcomes. Data collected by transmission electron microscope (TEM) on samples collected in the study mine showed that DPM-dust attachment does indeed occur. Moreover, the study results suggest that respirable particulate sampling — as opposed to submicron sampling, which is currently used — may be favorable for ensuring that oversized DPM is not excluded from samples. This strategy may require additional sample preparation to minimize dust interferences, but methods have been previously developed and were demonstrated here. / Master of Science

Diesel particulate matter (DPM) is the solid portion of diesel exhaust. DPM occurs primarily in the submicron range, and poses a number of respiratory and other health hazards including cardiovascular and pulmonary disease. Underground miners typically have the highest DPM exposures compared to other occupations. This is because many mines are characterized by confined work spaces and large diesel equipment fleets. Exposures can be a particularly high hazard in large opening mines where ventilation can be challenging. As such, DPM monitoring is critical to protecting miner health and informing a range of engineering decisions. DPM is primarily composed of two components, elemental carbon (EC) and organic carbon (OC), which are often summed to report total carbon (TC). The ratio of EC to OC, and presence of a number of other minor constituents such as sorbed metals, can vary with many factors such as engine operating conditions, maintenance, fuel types and additives, and the level and type of exhaust after-treatments used. Given its complexity, DPM cannot be measured directly, and either TC or EC are generally used as a surrogate. Currently, the Mining Safety and Health Administration (MSHA) limits personal exposures of underground metal/non-metal miners to 160 µg TC/m3 on an 8-hr time weighted average basis. Compliance is demonstrated by collecting full-shift personal filter samples, which are later analyzed using the NIOSH 5040 Standard Method. For engineering purposes, area samples can also be collected and analyzed. The typical lag time between sample collection and reporting of results is on the order of weeks, and this presents a real problem for identifying and remediating conditions that led to overexposures or high DPM in area samples. The handheld FLIR Airtec monitor was developed to provide real-time DPM data and allow immediate decision making. The monitor works on a laser extinction principle to measure EC, the black component of DPM, as mass accumulates on a filter. The Airtec has proven useful for personal monitoring and short-term DPM surveying. However, capabilities are needed for continuous, long-term monitoring. Continuous DPM monitoring would be highly valuable for applications such as design and operation of ventilation on demand systems, or engineering studies of new ventilation, exhaust treatment or other DPM controls. The work presented in this thesis considers three continuous monitors, two of which are already commercially available: Magee Scientific's AE33 black carbon (BC) Aethalometer and Sunset Laboratory's Semi-Continuous OCEC Field Analyzer. The third monitor, called the Airwatch, is still in development. The AE33 and Airwatch effectively operate on the same principle as the Airtec, but include a self-advancing filter tape to allow autonomous operation over relatively long periods of time. The OCEC field monitor is essentially a field version of the laboratory analyzer used for traditional 5040 Method analysis. The AE33 has been briefly demonstrated in mine environments in a couple of other studies, but further testing is needed. The current prototype of the Airwatch and the OCEC field monitor have never been mine-tested. Two separate studies are reported here. The first is a field study in an underground stone mine that tested the Airwatch prototype and AE33 head-to-head under relatively high DPM conditions. Results demonstrated that both instruments could track general trends, but that further work was needed to identify and resolve issues associated with use of both instruments in high-DPM environments – and with basic design elements of the Airwatch. Additionally, the need to calibrate the monitors' output data to the standard measure of EC (i.e., 5040 Method EC) was made clear. In the second study, laboratory testing was conducted under very controlled conditions to meet this need, and another round of field testing was also done. The second study also included the OCEC field monitor. The laboratory tests yielded data to allow interpretation of the AE33 and Airwatch results with respect to 5040 EC. These tests also shed light on the current range EC concentrations over which these monitors can provide reliable data – which is indeed a primary range of interest for mines. As expected, the OCEC field monitor was shown to produce lab-grade results across a wide range of concentrations. The field testing in the second study demonstrated that all three monitors could operate autonomously in a mine environment over extended periods of time (i.e., weeks to months). Overall, it can be concluded that the AE33 and OCEC field monitor represent off-the-shelf options for DPM monitoring in mines, and the Airwatch might be another option if fully developed in the future. Selection of a particular monitoring tool should include careful consideration of specific factors including data quality needs, conditions in the intended monitoring location(s), and general user friendliness of the monitor. / Master of Science

Air quality permits are required for the construction of all new surface mining operations. An air quality permit requires a surface mining operation to estimate the type and amount of pollutants the facility will produce. During surface mining the most common pollutant is particulate matter having an aerodynamic diameter less than 10 microns (PM10). The Industrial Source Complex (ISC3) model, created by the United States Environmental Protection Agency (U.S. EPA), is a model used for predicting dispersion of pollutants from industrial facilities, including surface mines and quarries. The use of this model is required when applying for a surface mining permit. However, the U.S. EPA and mining companies have repeatedly demonstrated that this model over-predicts the amount of PM10 dispersed by surface mining facilities, resulting in denied air quality permits. Past research has shown that haul trucks create the majority (80-90%) of PM10 emissions from surface mining operations. Therefore, this research concentrated on improving the ISC3 model by focusing on modeling PM10 emissions from mobile sources, specifically haul trucks at surface mining operations. Research into the ISC3 model showed that its original intended use was for facilities that emit pollutants via smoke stacks. The method used to improve the ISC3 model consisted of applying the dispersion equation used by the ISC3 model in a manner more representative of a moving haul truck. A new model called the Dynamic Component Program was developed to allow modeling of dust dispersion from haul trucks. To validate the Dynamic Component Program, field experiments were designed and conducted. These experiments measured PM10 from haul trucks at two different surface mining operations. The resulting analysis of the Dynamic Component Program, ISC3 model, and the actual field study results showed that the Dynamic Component Program was a 77% improvement over the ISC3 model overall. / Ph. D.

Achieving optimization of IMTA sites and modeling the efficiency of such a system requires knowledge of the spatiotemporal distribution and variability of TPM surrounding the finfish farms. The objective of this study was to quantify the impact of finfish farms on the surrounding particle field. Platforms equipped with transmissometers, fluorometers and CTD’s were towed around the sites while undulating through the water column in a high-resolution 3D spatial survey approach. In addition, combination turbidity and chlorophyll a sensors were moored at a variety of locations and depths. Surveys were conducted concurrently with the deployment of current meters. Farms surveyed were found to have little impact on the surrounding suspended particle field (mean effect < 1 mg L-1). Results provided evidence of minimal enhancement from fish farm wastes, primarily in surficial waters (0.5- 2 m depth) immediately adjacent to the cages, and evidence of predominantly tidal driven (M2) TPM dynamics.

Master of Science / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Large cattle feedlots in Kansas are often considered to be large sources of particulate matter (PM), including PM with equivalent aerodynamic diameter of 10 micrometers or less (PM[subscript]10). To control PM emissions from cattle feedlots, water sprinkler systems can be implemented; however, limited data are available on their PM control efficiency. This research was conducted to determine the control efficiency of a water sprinkler system in reducing PM[subscript]10 emission from a cattle feedlot. This was accomplished by monitoring the PM[subscript]10 concentrations, with tapered element oscillating microbalance (TEOM™) PM[subscript]10 monitors, at the upwind and downwind boundaries of a cattle feedlot (KS1) from January 2006 to July 2009. The feedlot was equipped with a sprinkler system that can apply up to 5 mm of water per day. It had approximately 30,000 head of beef cattle and total pen area of approximately 50 ha. The control efficiency of the sprinkler system was determined by considering the PM[subscript]10 data during sprinkler on/off events, i.e., the sprinkler system was operated (on) for at least one day and either followed or preceded by at least one day of no water sprinkling (off). For each of the selected sprinkler on/off events, the percentage reduction in net PM[subscript]10 concentration was calculated and considered to be a measure of the control efficiency. Net PM[subscript]10 concentration was defined as the difference between downwind and upwind PM[subscript]10 concentrations. The control efficiency for PM[subscript]10 ranged from 32% to 80%, with an overall mean of 53% based on 24-h PM[subscript]10 values for 10 sprinkler on/off events. In general, the effect of the water sprinkler system in reducing net PM[subscript]10 concentration lasted for one day or less. The percentage reduction in net PM[subscript]10 concentration at KS1 due to rainfall events was also determined using a similar approach. In addition, a second cattle feedlot (KS2) that was not equipped with a sprinkler system and with approximately 25,000 head of beef cattle and 68 ha pen area was considered. Percentage reductions in net PM[subscript]10 concentrations due to rainfall events were mostly in the range of 60% to almost 100% for both feedlots, with overall means of 75% for KS1 and 74% for KS2. The effects of rainfall events (with rainfall amounts > 10 mm/day) lasted for three to seven days, depending on rainfall amount and intensity. Limited data are also available on PM[subscript]10 emission rates from cattle feedlots in Kansas. This research quantified PM[subscript]10 emission rates from the two feedlots (KS1 and KS2) and a third cattle feedlot (KS3) in Kansas by using inverse dispersion modeling with the AMS/EPA Regulatory Model (AERMOD), which is the US EPA preferred regulatory atmospheric dispersion model. PM[subscript]10 emission rates were back-calculated using the resulting PM[subscript]10 concentrations modeled by AERMOD, together with measured PM[subscript]10 concentrations (24 months of data for KS1 and KS2, 6 months of data for KS3). Overall mean PM[subscript]10 emission fluxes for the 2-year period were 1.29 g/m[superscript]2-day (range: 0.04 – 4.98 g/m[superscript]2-day) for KS1, 1.03 g/m[superscript]2-day (range: 0.07 – 4.52 g/m[superscript]2-day) for KS2, and 2.48 g/m[superscript]2-day (6-months; range: 0.05 – 5.00 g/m[superscript]2-day) for KS3. The corresponding mean PM[subscript]10 emission factors were 21, 29, and 48 kg/1,000 hd-day for KS1, KS2, and KS3, respectively. The emission factors for KS1 and KS2 were considerably smaller than the published US EPA emission factor for cattle feedlots (i.e., 42 kg/1000 hd-day). The emission factor for KS3 was slightly greater than the US EPA emission factor; however, it was a biased estimate because it was based only on a six-month period.

The promulgation of revised standards for atmospheric fine particles (PM2.5) by the US EPA has sparked renewed interest in the ability to accurately measure and characterize suspended atmospheric particulate matter. Semi-volatile material (SVM), consisting of ammonium nitrate and semi-volatile organic material (SVOM), is not accurately measured by EPA accepted methods such as the Federal reference method (FRM) or Tapered Element Oscillating Microbalance (TEOM). However, SVM is often a major fraction of urban aerosols. Recent advances in atmospheric sampling instrumentation allowed for the semi-continuous characterization of urban PM2.5, including SVM. The Filter Dynamic Measurement System (FDMS) was shown to measure total PM2.5 mass including semi-volatile species. Validation of the FDMS was performed by comparison with the particle concentrator-Brigham Young University organic sampling system (PC-BOSS) and the real-time total ambient mass sampler (RAMS). Semi-continuous ambient particulate concentrations of sulfate, nitrate and ammonium ion were measured by a newly developed Dionex instrument which was field tested and validated for the first time in Fresno, CA. Either a modified Sunset Laboratory carbon monitor, collocated with a conventional Sunset carbon monitor employing a common inlet, or the newly developed dual-oven Sunset monitor allowed for the semi-continuous determination of both nonvolatile and semi-volatile organic material. This was the first attempt to characterize both nonvolatile and semi-volatile fractions of an urban aerosol in a semi-continuous manner using all semi-continuous instruments. A suite of instruments for semi-continuous PM2.5 monitoring was recommended including, an R&P FDMS for the measurement of PM2.5 mass, a dual-oven Sunset monitor for the measurement of nonvolatile and semi-volatile carbonaceous species, and a Dionex GP-IC for the measurement of inorganic species. A TEOM monitor is also recommended to measure nonvolatile PM2.5 mass. Using these instruments, semi-continuous mass closure was obtained for the first time during a study conducted in Riverside, CA. The advantage of using semi-continuous sampler data in the application of source apportionment was elucidated. Local aerosols are often impacted by short-term pollution episodes that cannot be temporally resolved using integrated samplers. One-h averaged data applied to source apportionment models was shown to increase the power of the model to predict sources, both primary and secondary, that exhibit diurnal short-term episodes.

Master of Science / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Military training lands can be significant sources of fugitive dust emissions due to wind erosion. This study was conducted to determine dust emission potential of soils due to wind erosion as affected by off-road military vehicle disturbance. Multi-pass traffic experiments using two types of vehicles (i.e., wheeled and tracked) were conducted on six soil textures at four military training facilities: Fort Riley, KS; Fort Benning, GA; Yakima Training Center, WA; and White Sands Missile Range (WSMR), NM. Prior to and after the preselected number of vehicle passes, soil samples at three locations were collected with minimum disturbance into trays. Adjacent to the location where tray samples were collected, a Portable In-Situ Wind Erosion Lab (PI-SWERL) was used to measure dust emission potential. The tray samples were tested in a laboratory wind tunnel (with sand abrader) for dust emission potential using a GRIMM aerosol spectrometer and gravimetric method with filters. Comparison of the PI-SWERL (with DustTrak™ dust monitor) and wind tunnel (with GRIMM aerosol spectrometer) measurement results showed significant difference in measured values but high correlation, particularly for soils with high sand content. Wind tunnel tests results showed that sampling locations significantly affected dust emissions for the tracked vehicles but not for the light-wheeled and heavy-wheeled vehicles. Also, soil texture, number of vehicle passes, and vehicle type significantly affected dust emissions. For the light-wheeled vehicles, dust emissions increased as the number of vehicle passes increased. From undisturbed conditions to 10 vehicle passes, there was a significant (P<0.05) increase in dust emissions (297%) on average for all light-wheeled vehicle tests. From 10 to 25 passes and 25 to 50 passes, an additional 52% and 62% increments were observed. For the tracked vehicle, for the straight section sampling location, dust emission increased as the number of vehicle passes increased. However, for the curve section, dust emissions at any level of pass were significantly higher than initial condition; beyond the first pass, no significant increase was observed.

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.