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Exposure of poultry farm workers to ammonia, particulate matter and microorganisms in the Potchefstroom district, South Africa / by A.C. de JagerDe Jager, Anna Catharina January 2005 (has links)
Motivation: The investigation of agricultural respiratory hazards has lagged behind
the investigation of hazards in mining and other heavy industries. Relatively few
epidemiological data are available addressing pulmonary infections in the context of
the agricultural work environment, especially for the South African population.
Poultry house dust was generally considered nuisance or inert, meaning it has little
adverse effect on human lungs. New research shows that because poultry house
dust is largely organic and contain bacteria and other bioactive substances, it cannot
be considered inert. Several published research manuscripts document that the
legal and recommended exposure limits for the toxic substances found in the
agricultural environment are to high for concentrated animal feeding operations
(CAFO's). In CAFO's there is a mixture of biologically active agents that can work
synergistic to produce respiratory and systemic effects at much lower levels. Most of
the current legal exposure limits used in South Africa are adopted from international
limits and guidelines. Because of the influence of geography, climate and degree of
industrialisation on the agricultural air quality, the relevance of the foreign exposure
limits is questionable.
Aim: To determine if there is a correlation between occupational exposure to poultry
farm dust and the lung function of poultry farm workers in the Potchefstroom district,
South Africa. Also to determine if the current legal exposure limits used for ammonia
and particulate matter (PM) in South Africa, offer adequate worker protection for
poultry farm workers exposed to biologically active dust.
Methodology: This was an observational, cross-sectional pilot study. A target
population of fifty contract workers concerned with the removal and disposal of
poultry manure were identified in the Potchefstroom district and a random sample of
nineteen was drawn for participation in this study. Exposure to total and respirable
dust were determined by means of personal sampling for the full duration of the time averaging
period (8-hour TWA). Area monitoring for ammonia and bio-aerosols were
done in poultry houses in three specific demarcated areas around Potchefstroom,
and weather conditions were taken into account. Lung function tests (spirometry)
were conducted before and after each work shift. Interviewer administered
questionnaires were used to assess occupational and exposure histories and to
detect symptoms of organic dust exposure.
Results and conclusions: The mean total- and respirable dust concentrations
complied with the legal limits of OSHA, NlOSH and the Regulations for hazardous
chemical substances of 1995. However, fifty five percent of the measured total dust
concentrations and all of the respirable dust measurements exceeded Donham's
recommended values for human health. The spirometric values of the subjects were
normal; there was no statistical difference between the mean baseline FEV1/FVC and
the mean predicted FEV1/FVC. Results also show no statistically significant cross
shift changes in any of the measured variables and there is no significant correlation
of the measured dust concentrations to any of the spirometric measurements. It can
be concluded that occupational exposure to ammonia, particulate matter and
micro-organisms on poultry farms in the Potchefsroom district, South Africa, do not
have any adverse effects on the workers' lung function and the workers are
adequately protected in the short term, by the legal limits that are currently used in
South Africa. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2006.
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Health effect of household fuel pollution on young children in semi-urban and urban areas of BangladeshNäsänen-Gilmore, S. P. K. January 2009 (has links)
Household fuel pollution from the use of low quality biomass fuels is considered as a risk factor for respiratory tract infections (RTI) in women and children. Inhalation of fuel-derived pulmonary toxins (e.g. particulate matter (PM2.5μm) , and carbon monoxide (CO) can harm the lungs of young children, due to their under-developed immune defences. In Bangladesh acute respiratory infections (ARI) are the leading cause of child mortality (< 5 years of age). This thesis aimed to examine the relationship between RTI and household fuel pollution exposure using measured pollution data and medical diagnoses. During an 18-month longitudinal health intervention in northern Bangladesh households (n=408) were interviewed (3 times) on cooking/fuel-use practices and child health. Anthropometric data (height/weight) and finger-prick blood samples for analysis of immune status (c-reactive protein, alpha-1-acidglycoprotein (AGP) and albumin) were collected (n=321 < 5 years of age). All unwell children (62.4%) were medically examined. Household pollution levels (particulate matter (PM2.5μm) and carbon monoxide (CO) were monitored for a 24-hour period (n=61). Moderate/ severe RTI was common (24.8%) (youngest child only n=213). Poor child growth (stunted: 43.8%, underweight=66.7%, wasted: 38.4%) and immunity were detected. 98% of the households used inefficient chimneyless mud stoves and low quality biomass fuels (wood, golden, dung). The measured indoor pollution levels exceeded the WHO safety thresholds (PM2.5 μm range: 85 to 3020 μg/m³ CO range: 0-16 ppm) (PM2.5 μm>25 μm/m³, CO>9ppm). Longitudinal multivariate GLM showed that cooking practices were associated with child immune status: haemoglobin levels (F= 1.555, p=NS) were significantly associated with Bihari ethnicity and a fixed stove use (F=3.718 and F=3.716, p<0.05 respectively). Elevated log₁₀-AGP levels were found (F=4.371, p<0.05) in Saidpur in households using a fixed stove (F=4.123, F=3.780, p<0.05). The patterns in child growth z-scores were due to age only (stunting: F=7.413, p<0.01, underweight F=5.787, p<0.05). Interestingly, poorer change score for weight-for-age (F=34.893, p<0.01) was associated with low age and more frequent cooking (F=6.441 and, F=6.553, p<0.05 respectively). Logistic regression (healthy vs. RTI) identified the presence of child by the stove during cooking as the sole risk factor for RTI (absent OR= 0.257, 95% CI: 0.097 - 0.676, p<0.01). Indoor cooking and the use of a fixed stove were associated with low SES. Education may help to reduce behaviours associated with high household fuel pollution exposure via the introduction of simple healthy cooking practices.
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Calibration and Characterization of Low-Cost Fine Particulate Monitors and their Effect on Individual EmpowermentTaylor, Michael D. 01 December 2016 (has links)
Air quality has long been a major health concern for citizens around the world, and increased levels of exposure to fine particulate matter (PM2:5) has been definitively linked to serious health effects such as cardiovascular disease, respiratory illness, and increased mortality. PM2:5 is one of six attainment criteria pollutants used by the EPA, and is similarly regulated by many other governments worldwide. Unfortunately, the high cost and complexity of most current PM2:5 monitors results in a lack of detailed spatial and temporal resolution, which means that concerned individuals have little insight into their personal exposure levels. This is especially true regarding hyper-local variations and short-term pollution events associated with industrial activity, heavy fossil fuel use, or indoor activity such as cooking. Advances in sensor miniaturization, decreased fabrication costs, and rapidly expanding data connectivity have encouraged the development of small, inexpensive devices capable of estimating PM2:5 concentrations. This new class of sensors opens up new possibilities for personal exposure monitoring. It also creates new challenges related to calibrating and characterizing inexpensively manufactured sensors to provide the level of precision and accuracy needed to yield actionable information without significantly increasing device cost. This thesis addresses the following two primary questions: 1. Can an inexpensive air quality monitor based on mass-manufactured dust sensors be calibrated efficiently in order to achieve inter-device agreement in addition to agreement with professional and federally-endorsed particle monitors? 2. Can an inexpensive air quality monitor increase the confidence and capacity of individuals to understand and control their indoor air quality? In the following thesis, we describe the development of the Speck fine particulate monitor. The Speck processes data from a low-cost dust sensor using a Kalman filter with a piecewise sensing model. We have optimized the parameters for the algorithm through short-term co-location tests with professional HHPC-6 particle counters, and verified typical correlations between the Speck and HHPC-6 units of r2 > 0:90. To account for variations in sensitivity, we have developed a calibration procedure whereby fine particles are aerosolized within an open room or closed calibration chamber. This allows us to produce Specks for commercial distribution as well as the experiments presented herein. Drawing from previous pilot studies, we have distributed low-cost monitors through local library systems and community groups. Pre-deployment and post-deployment surveys characterize user perception of personal exposure and the effect of a low-cost fine particulate monitor on empowerment.
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Evaluation Of The Engine Exhaust Particle Sizer (eeps) For Real-Time Measurements Of Diesel And Biodiesel Exhaust Particulate MatterDunshee, James Robert 01 January 2016 (has links)
Even at low concentrations, the criteria air pollutant particulate matter (PM) is an environmental and public health hazard. Emissions levels legislated for modern diesel vehicles are so low (~90% lower than 2003) that it has become difficult to accurately measure PM by the regulatory metric: the mass of particles collected on a filter (i.e., the gravimetric method). Additionally, gravimetric analysis cannot measure real-time emission rates, and therefore is unable to characterize high-emitting transient events (e.g., engine starts, stop-and-go driving). By an alternate method, PM can be estimated by measuring the number-weighted particle size distribution (PSD) and calculating mass with a combination of theoretical and empirical constants (e.g., particle effective density). This integrated particle size distribution (IPSD) method is capable of high measurement sensitivity and real-time resolution.
Real-time measurements by the IPSD method require fast-sizing spectrometers, such as the TSI Engine Exhaust Particle Sizer (EEPS), which sizes (between 5.6-560 nm) and counts particles based on their electrical mobility. The EEPS utilizes a unipolar charger to quickly charge particles for sizing and counting, however this mechanism has been shown to produce a less predictable charge distribution than bipolar chargers used in Scanning Mobility Particle Sizer (SMPS) systems – the gold standard 'slow-sizing' spectrometer. Several evaluations have shown deficiencies in EEPS PSD measurements due to charging differences (associated with particle morphology) unaccounted for in the transfer function matrix used to calibrate the EEPS. Specifically, the unipolar charger multiply charges a higher percentage of soot agglomerates (fractal-like particles common in diesel engine exhaust) than bipolar chargers. Because inaccurate PSDs are a primary reason for reported discrepancies between IPSD calculated mass and the gravimetric method, it is important to correct this deficiency in EEPS measurements. Recently, TSI has released additional EEPS calibration matrices ('soot' and 'Compact') which have shown better agreement with SMPS measurements under preliminary test conditions. This study further evaluates the performance of these new matrices relative to the original 'Default' matrix for diesel and biodiesel exhaust particles.
Steady-state (75% engine load) emissions were generated by a light-duty diesel engine operating on (1) ultra-low sulfur diesel (ULSD) and (2) 100% soybean biodiesel. Raw EEPS data processed with each matrix were compared to simultaneously collected reference measurements from an SMPS. PSDs were evaluated based on their shape – i.e., multimodal fits of geometric mean diameter (GMD) and geometric standard deviation (GSD) – and concentration at peak particle diameter. For both fuels, all measurements agreed well in terms of the shape of the PSD: primary mode (accumulation) GMD ± 10nm, GSD ± 0.3. For ULSD, EEPS Default, Soot, and Compact concentrations were higher than the SMPS by factors of 1.9, 1.3, and 2.5, respectively. For biodiesel, EEPS Default, Soot, and Compact concentrations were higher than the SMPS by factors of 2.1, 1.7, and 2.4, respectively. Based on these results, the Soot matrix produced acceptable agreement between EEPS and SMPS measurements of ULSD exhaust particles. However, based on the factor of ~2 difference observed here, an additional calibration matrix may be necessary for the EEPS to accurately measure biodiesel exhaust particles.
The IPSD method for estimating PM mass was applied to available data sets with corresponding gravimetric measurements (one ULSD transient cycle test and the same biodiesel steady-state test used for PSD evaluation). Real-time PSDs from each of the three EEPS matrices were used in combination with three sets of values assumed for size-dependent particle effective density (representing a range of potential conditions), resulting in nine IPSD estimates of PM mass corresponding to each gravimetric sample (one ULSD, one biodiesel). For the transient ULSD test, a widely used effective density distribution for fractal-like soot agglomerates resulted in good agreement between IPSD estimated mass and the gravimetric measurement (within 9% and 6% for Soot and Compact matrices, respectively). For the steady-state biodiesel test, assuming unit density (1g/cm³ for all particles) resulted in good agreement between IPSD estimated mass and the gravimetric measurement (within 7% and 2% for Soot and Compact matrices, respectively). These results support previous findings that the Soot matrix is currently the best available option for measurement of ULSD exhaust particles by the EEPS and that particle effective density distributions similar to the "fractal-like" one used here are an accurate estimate for ULSD exhaust particles under many conditions. However, based on the discrepancies between the EEPS and SMPS measured biodiesel exhaust PSDs observed here, as well as a current lack of information on the effective density of biodiesel exhaust particles, it is clear that additional research is necessary in order to understand the properties of biodiesel exhaust particles, especially as they relate to electrical mobility measurements and IPSD estimation of PM mass.
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Determination of Size Fractions and Concentrations of Airborne Particulate Matter Generated From Construction and Demolition Waste Processing FacilitiesYoung, Jason M. 01 January 2007 (has links)
Construction and Demolition (C&D) processing and recycling facilities accept waste materials that are generated during construction and demolition activities. The processing facility sorts, processes, and transfers the material to another operation. A consequence of these processes is the generation of particulate matter.This study involved quantifying and qualifying airborne particulates at three C&D processing facilities. Active stationary particulate sampling devices were employed to quantify the particle sizes of interest. Results were compared to United States Environmental Protection Agency (EPA) National Ambient Air Quality Standards(NAAQS) and United States Occupational Safety and Health Administration (OSHA)standards.The results from this study are not valid for determination of compliance with NAAQS or OSHA standards. However, the data indicate that C&D processing facilities may exceed current NAAQS at certain locations, but do not exceed OSHA standards. These results can be used by the industry as an engineering tool to reduce airborne particulate levels during normal operations of C&D facilities.
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Vliv vlny vedra v létě 2003 a 2006 na úmrtnost obyvatel Prahy / Heat wave effect on mortality in summer 2003 and 2006 in PragueKnobová, Veronika January 2012 (has links)
Background: During August 2003 and July 2006 there were observed records of high temperature and high concentrations of pollutants across Europe. The effect of heat waves led to significant increases in total mortality, respiratory mortality and cardiovascular mortality. This study evaluates the association between exposure to the heat waves and daily non- accidental mortality, respiratory mortality and cardiovascular mortality in Prague, the Czech Republic. Methods: The effect of heat waves in summer 2003 and 2006 on mortality was investigated using the negative binomial regression (type of the Poisson model). Counts of death were regressed on temperature, long-term trends, season, day of week and concentrations of pollutants (O3 levels, PM10 levels, NO2 levels, SO2 levels, CO levels). We used one day lag. Results: We found an association between the heat waves in summer 2003 and 2006 and daily mortality and mortality on respiratory and cardiovascular diseases. No statistically significant association was detected. The effect of the heat wave was more significant in women. Conclusions: The effect of the heat wave in August 2003 and July 2006 caused adverse effect on the mortality in Prague, though lower as compared to many other cities in Europe. Keywords: heat wave, mortality, temperature, ozone,...
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Fugitive dust emissions from off-road vehicle maneuvers on military training landsMeeks, Jeremy C. January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Ronaldo G. Maghirang / Military installations in the United States may be large sources of fugitive dust emissions. Off-road vehicle training can contribute to air quality degradation resulting from increased wind erosion events as a result of soil disruption; however, limited information exists regarding the impacts of off-road vehicle maneuvering. This study was conducted to determine the effects of soil texture and intensity of training with off-road vehicles on fugitive dust emission potential due to wind erosion at military training installations.
Multi-pass trafficking experiments, involving wheeled and tracked military vehicles (i.e., M1A1 Abrams tank, M925A1 water tanker and various HMMWV models), were conducted at three military training facilities with different climate and soil texture (i.e., Fort Riley, KS; Fort Benning, GA; and Yakima Training Center, WA). Dust emissions were measured on site using a Portable In-Situ Wind Erosion Laboratory (PI-SWERL) coupled with a DustTrak™ dust monitor. In addition, a top layer of soil was collected in trays and tested in a laboratory wind tunnel for dust emission potential. In wind tunnel testing, the amount of emitted dust was measured using glass-fiber filters through high-volume samplers. Also, the particle size distribution and concentration of the emitted dust were measured using a GRIMM aerosol spectrometer.
Comparison of the PI-SWERL (with DustTrak™ dust monitor) and wind tunnel test (with GRIMM aerosol spectrometer) results showed significant difference and little correlation. Also, comparison of the filter and GRIMM aerosol spectrometer data showed significant difference but high correlation. The dust emission potential (as measured with the GRIMM spectrometer) was significantly influenced by soil texture, vehicle type and number of passes. For the light-wheeled vehicle, total dust emissions increased from 66 mg m-2 for undisturbed soil to 304 mg m-2 (357%) and 643 mg m-2 (868%) for 10 and 50 passes, respectively. For the tracked vehicle, an average increase in total dust emission of 569% was observed between undisturbed conditions and 1 pass, with no significant increase in emissions potential beyond 1 pass. For the heavy-wheeled vehicle, emissions increased from 75 mg m-2 for undisturbed soil to 1,652 mg m-2 (1,369%) and 4,023 mg m-2 (5,276%) for 10 and 20 passes, respectively. Soil texture also played an important role in dust emission potential. For all treatment effects, there was a 1,369% difference in emissions between silty clay loam soil and loamy sand soil.
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Performance and Total PM Emission Factor Evaluation of Expendable AbrasivesKambham, Kalpalatha 22 May 2006 (has links)
Dry abrasive blasting is one of the most widely used methods of surface preparation. Air emissions from this process include particulate matter (PM) and metals. Spent abrasive generated from this process may be hazardous in nature. With increasing concern on health effects due to silica emissions from sand, use of alternative materials is suggested by health and regulatory agencies. The objective of this research was to evaluate performance of expendable abrasives and determine PM emission factors. Dry abrasive blasting was performed in an enclosed chamber and total PM samples were collected. Three commonly used expendable abrasives, coal slag, copper slag and specialty sand, were used to evaluate cleaner alternatives. Blast pressure and abrasive feed rate, two important process conditions were varied to study their effect on performance of an abrasive. Productivity, consumption and emission factors (performance parameters) were calculated and their variation with pressure and feed rate was evaluated. Two dimensional and three dimensional predicted models were developed to estimate the performance at intermediate blast pressure and feed rate conditions. Performance of the three abrasives was compared with respect to emission potential, productivity and consumption. Emission factors developed in this research will help in accurate estimation of total PM emissions and to select cleaner abrasives and optimum process conditions that will results in minimum emissions and reduced health risk. The productivity and consumption models will help is estimating life cycle costs including material cost, equipment cost, energy cost, labor costs, waste disposal cost, and compliance costs. Consumption models will also help in determining the quantity of spent abrasive generated, identify abrasives with lower material consumption, and identify process conditions that generate minimum spent abrasives. In addition, these models will help industries in making environmentally preferable purchasing (EPP), which results in pollution prevention and cost reduction.
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Evaluation of Productivity, Consumption, and Uncontrolled Total Particulate Matter Emission Factors of Recyclable AbrasivesSangameswaran, Sivaramakrishnan 22 May 2006 (has links)
Dry abrasive blasting is a commonly used surface preparation operation by many process industries to clean up metallic surfaces and achieve surface finishes suitable for future adhesion. Abrasives used in this process can be recyclable or expendable. This study was undertaken to evaluate the performance of three recyclable abrasives: garnet, barshot and steel grit/shot in terms of productivity (area cleaned per unit time), consumption (amount of abrasive used per unit area cleaned) and uncontrolled total particulate matter (TPM) emission factors (in terms of mass of pollutant emitted per unit area cleaned and mass of pollutant emitted per unit mass of abrasive consumed). Though there have been various attempts in the past to evaluate the performance of these abrasives, there has not been a streamlined approach to evaluate these parameters in the commonly used range of process conditions, or to identify and model the influences of key process variables on these performance parameters. The first step in this study was to evaluate the performance of these three abrasives in blasting painted steel panels under enclosed blasting conditions and using USEPA recommended protocols. The second step was to model the influences of blast pressure and abrasive feed rate, two most critical parameters on productivity, consumption and emission factors. Two and three dimensional models were obtained using multiple linear regression techniques to express productivity, consumption and TPM emission factors in terms of blast pressure and abrasive feed rate. Barshot was found to have high productivities over all and steel grit/shot demonstrated the least emission potential at almost all of the tested pressure and feed rate conditions. The data will help fill the gaps in literature currently available for dry abrasive blasting performance. The models obtained will help industries, the research community and the regulatory agencies to make accurate estimates of the performance parameters. Estimating productivity and consumption will help industries identify best management practices by optimizing the process conditions to achieve high productivity and low consumption rates. Emission factor determination will help in reducing the emissions to the atmosphere by choosing process conditions corresponding to minimum emissions. The performance parameters once optimized can result in reduction in material, labor, energy, emission and disposal costs, lower resource utilization and hence reduction in overall life cycle costs of dry abrasive process. The developed models will help industries in making environmentally preferable purchases thereby promoting source reduction options. PM emissions estimated using the models presented here will aid studies on health risk associated with inhalation of atmospheric PM.
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Resposta molecular do endotélio pulmonar à exposição aguda de material particulado fino / Molecular response of pulmonary endothelial cells to acute exposure to fine particulate matterAlameddine, Mirna 03 March 2010 (has links)
Estudos epidemiológicos estabelecem uma associação evidente entre poluição do ar e o aumento de morbimortalidade cardiovascular e respiratória. No entanto, os mecanismos moleculares subjacentes aos efeitos do material particulado fino (MP2,5) sobre o organismo ainda estão pouco esclarecidos. O objetivo deste trabalho foi caracterizar o impacto da exposição ao MP2,5 sobre a biologia do endotélio pulmonar e do coração, através da avaliação do perfil de expressão gênica por microarray. Camundongos adultos fêmeas foram anestesiados e submetidos à instilação intratraqueal de MP2,5 (grupo exposto) ou veículo (grupo controle). Os animais foram sacrificados 12 a 18 horas após a instilação e pulmão, coração e sangue da veia cava inferior foram coletados. Os pulmões foram dissociados com colagenase tipo I e células endoteliais foram positivamente selecionadas por captura imuno-magnética através de micro-ímãs acoplados a anti-CD31. O cRNA derivado de endotélio pulmonar e de coração total foi hibridizado em membrana de microarray de baixa densidade desenhada para representar genes relevantes à biologia endotelial. Os genes encontrados diferencialmente expressos no pulmão foram Itgb1, Cxcl1, Tnf, Ecgf1 e Tnfaip3 (hiper-expressos em expostos a MP2,5) e Enpep, Pdgfra, Gzmb, Birc2, Npr1, Angpt1, Cxcl5 e Il7 (hipo-expressos). Não foi possível realizar análise de inferência estatística de membranas do coração neste trabalho. Não houve diferença estatisticamente significativa entre os grupos exposto e controle na contagem sangüínea de neutrófilos, linfócitos ou plaquetas, apesar dos dois grupos apresentarem plaquetose. Os achados indicam que MP2,5 altera a transcrição de genes envolvidos não só na inflamação e estresse oxidativo, mas também no tônus e remodelamento vascular, que podem ser os responsáveis pelos efeitos cardiovasculares agudos do MP2,5 / Epidemiological studies establish a clear association between air pollution and increased cardiovascular and respiratory morbidity and mortality. However, the molecular mechanisms underlying the effect of fine particulate matter (PM2,5) are still poorly understood. The aim of this study was to characterize the impact of exposure to PM2,5 on the biology of pulmonary endothelium and the heart, through the assessment of gene expression profiling by microarray. Adult female mice were anesthetized and submitted to intratracheal instillation of either PM2,5 (challenged group) or vehicle (control group). The animals were sacrificed 12 to 18 hours after instillation and lung, heart and blood samples from the inferior vena cava were collected. The lungs were dissociated with collagenase type I and endothelial cells were positively selected by immuno-magnetic capture through microbeads coupled to anti-CD31. The cRNA derived from the pulmonary endothelial cells and heart were hybridized to low-density microarray designed specifically to represent genes relevant to endothelial biology. Genes found differentially expressed in the lung were Itgb1, Cxcl1, Tnf, Ecgf1, and Tnfaip3 (over-expressed in challenged group) and Enpep, Pdgfra, Gzmb, Birc2, Npr1, Angpt1, Cxcl5 and IL7 (under-expressed). It was not possible to perform statistical inference of heart samples in this study. There was no statistically significant difference between challenged and control groups in blood counts of neutrophils, lymphocytes or platelets, despite both groups presented increased number of platelets. The findings indicate that PM2,5 alters transcription of genes involved not only in inflammation and oxidative stress, but also in vascular tonus and remodeling, which may be responsible for the acute cardiovascular effects of PM2,5
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