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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

New Opportunities in Crowd-Sourced Monitoring and Non-government Data Mining for Developing Urban Air Quality Models in the US

Lu, Tianjun 15 May 2020 (has links)
Ambient air pollution is among the top 10 health risk factors in the US. With increasing concerns about adverse health effects of ambient air pollution among stakeholders including environmental scientists, health professionals, urban planners and community residents, improving air quality is a crucial goal for developing healthy communities. The US Environmental Protection Agency (EPA) aims to reduce air pollution by regulating emissions and continuously monitoring air pollution levels. Local communities also benefit from crowd-sourced monitoring to measure air pollution, particularly with the help of rapidly developed low-cost sampling technologies. The shift from relying only on government-based regulatory monitoring to crowd-sourced effort has provided new opportunities for air quality data. In addition, the fast-growing data sciences (e.g., data mining) allow for leveraging open data from different sources to improve air pollution exposure assessment. My dissertation investigates how new data sources of air quality (e.g., community-based monitoring, low-cost sensor platform) and model predictor variables (e.g., non-government open data) based on emerging modeling approaches (e.g., machine learning [ML]) could be used to improve air quality models (i.e., land use regression [LUR]) at local, regional, and national levels for refined exposure assessment. LUR models are commonly used for predicting air pollution concentrations at locations without monitoring data based on neighboring land use and geographic variables. I explore the use of crowd-sourced low-cost monitoring data, new/open dataset from government and non-government sponsored platforms, and emerging modeling techniques to develop LUR models in the US. I focus on testing whether: (1) air quality data from community-based monitoring is feasible for developing LUR models, (2) air quality data from non-government crowd-sourced low-cost sensor platforms could supplement regulatory monitors for LUR development, and (3) new/open data extracted from non-government sponsored platforms could serve as alternative datasets to traditional predictor variable sources (e.g., land use and geographic features) in LUR models. In Chapter 3, I developed LUR models using community-based sampling (n = 50) for 60 volatile organic compounds (VOC) in the city of Minneapolis, US. I assessed whether adding area source-related features improves LUR model performance and compared model performance using variables featuring area sources from government vs. non-government sponsored platforms. I developed three sets of models: (1) base-case models with land use and transportation variables, (2) base-case models adding area source variables from local business permit data (government sponsored platform), and (3) base-case models adding Google point of interest (POI) data for area sources. Models with Google POI data performed the best; for example, the total VOC (TVOC) model had better goodness-of-fit (adj-R2: 0.56; Root Mean Square Error [RMSE]: 0.32 µg/m3) as compared to the permit data model (0.42; 0.37) and the base-case model (0.26; 0.41). This work suggests that VOC LUR models can be developed using community-based samples and adding Google POI could improve model performance as compared to using local business permit data. In Chapter 4, I evaluated a national LUR model using annual average PM2.5 concentrations from low-cost sensors (i.e., PurpleAir platform) in 6 US urban areas (n = 149) and tested the feasibility of using low-cost sensor data for developing LUR models. I compared LUR models using only the PurpleAir sensors vs. hybrid LUR models (combining both the EPA regulatory monitors and the PurpleAir sensors). I found that the low-cost sensor network could serve as a promising alternative to fill the gaps of existing regulatory networks. For example, the national regulatory monitor-based LUR (i.e., CACES LUR developed as part of the Center for Air, Climate, and Energy Solutions) may fail to capture locations with high PM2.5 concentrations and the within-city spatial variability. Developing LUR models using the PurpleAir sensors was reasonable (PurpleAir sensors only: 10-fold CV R2 = 0.66, MAE = 2.01 µg/m3; PurpleAir and regulatory monitors: R2 = 0.85, MAE = 1.02 µg/m3). I also observed that incorporating PurpleAir sensor data into LUR models could help capture within-city variability and merit further investigation on areas of disagreement with the regulatory monitors. This work suggests that the use of crowd-sourced low-cost sensor networks for LUR models could potentially help exposure assessment and inform environmental and health policies, particularly for places (e.g., developing countries) where regulatory monitoring network is limited. In Chapter 5, I developed national LUR models to predict annual average concentrations of 6 criteria pollutants (NO2, PM2.5, O3, CO, SO2 and PM10) in the US to compare models using new data (Google POI, Google Street View [GSV] and Local Climate Zone [LCZ]) vs. traditional geographic variables (e.g., road lengths, area of built land) based on different modeling approaches (partial least square [PLS], stepwise regression and machine learning [ML] with and without Kriging effect). Model performance was similar for both variable scenarios (e.g., random 10-fold CV R2 of ML-kriging models for NO2, new vs. traditional: 0.89 vs. 0.91); whereas adding the new variables to the traditional LUR models didn't necessarily improve model performance. Models with kriging effect outperformed those without (e.g., CV R2 for PM2.5 using the new variables, ML-kriging vs. ML: 0.83 vs. 0.67). The importance of the new variables to LUR models highlights the potential of substituting traditional variables, thus enabling LUR models for areas with limited or no data (e.g., developing countries) and across cities. The dissertation presents the integration of new/open data from non-government sponsored platform and crowd-sourced low-cost sensor networks in LUR models based on different modeling approaches for predicting ambient air pollution. The analyses provide evidence that using new data sources of both air quality and predictor variables could serve as promising strategies to improve LUR models for tracking exposures more accurately. The results could inform environment scientists, health policy makers, as well as urban planners interested in promoting healthy communities. / Doctor of Philosophy / According to the US Centers for Disease Control and Prevention (CDC), a healthy community aims at preventing disease, reducing health gaps, and creating more accessible options for a wider population. Outdoor air pollution has been evidenced to cause a wide range of diseases (e.g., cardiovascular diseases, respiratory diseases, diabetes and adverse birth outcome), ranking as the top 10 health risks in the US. Thus, improving understanding of ambient air quality is one of the common goals among environmental scientists, urban planners, health professionals, and local residents to achieving healthy communities. To understand air pollution exposures in different areas, US Environmental Protection Agency (EPA) has regulatory monitors for outdoor air pollution measurements across the country. For locations without these regulatory monitors, land use regression (LUR) models (one type of air quality models) are commonly employed to make a prediction. Usually, information including number of people, location of bus stops, and type of roads are shared online from government websites. These datasets are often used as significant predictor variables for developing LUR models. Questions remain on whether new air quality data and alternative land use data from non-government sources could improve air quality modeling. In recent years, local communities have been actively involving in air pollution monitoring using rapidly developed low-cost sensors and sampling campaigns with the help of local residents. In the meantime, advances in data sciences make open data much easier to acquire and use, particularly from non-government sponsored platforms. My dissertation aims to explore the use of new data sources including community-based low-cost monitoring data and open dataset from non-government websites in LUR modes based on emerging modeling techniques (e.g. machine learning) to predict air pollution levels in the US. I first built LUR models for volatile organic compounds (VOC: organic chemicals with a high vapor pressure at room temperature [e.g., Benzene]) based on community-based sampling data in the City of Minneapolis, US. I added information on number of neighboring gas stations, dry cleaners, paint booths, and auto shops from both the local government and Google website into the model and compared the model performance for both data sources (Chapter 3). Then, I used PM2.5 data from a non-government website (PurpleAir low-cost sensors) for 6 US cities evaluating an existing air quality model that used air quality data from government websites. I further developed LUR models using the PurpleAir PM2.5 data to see whether this non-government source of low-cost sensor data could be as reasonable as the government data for LUR model development. I finally extracted new/open data from non-government sponsored platforms (e.g., Google products and local climate zone [LCZ: a map that describes the development patterns of land, such as high-rise vs. low-rise or trees vs. sands]) in the US to investigate if these data sources can be used to alternate the land use and geographic data often used in national LUR model development. I found that: (1) adding information (e.g., number of neighboring gas stations) from non-government sponsored sources (e.g., Google) could improve the air quality model performance for VOCs, (2) integrating non-government low-cost PM2.5 sensor data into government regulatory monitoring data to develop LUR models could improve model performance and offer more insights on the air pollution exposure, (3) new/open data from non-government sponsored platforms could be used to replace the land use and geographic data previous obtained from government websites for air quality models. These findings mean that air quality data and street-level land use characteristics could serve as alternative data sources and are capable of developing better air quality models for promoting healthy communities.
112

(137)Cs concentrations in foliose lichens within Tsukuba-city as a reflection of radioactive fallout from the Fukushima Dai-ichi Nuclear Power Plant accident

Ohmura, Y., Matsukura, K., Abe, J.P., Hosaka, K., Tamaoki, M., Dohi, T., Kakishima, M., Seaward, Mark R.D. 03 1900 (has links)
No / (137)Cs concentrations in ten species of foliose lichens collected within Tsukuba-city in August 2013 ranged from 1.7 to 35 kBq/kg. The relationships between (137)Cs in two dominant species, Dirinaria applanata and Physcia orientalis, and the air dose rate (muSv/h) at the sampling sites were investigated. (137)Cs in P. orientalis measured about 1 year after the Fukushima nuclear accident was correlated (r(2) = 0.80) more closely with the air dose rate than those measured after about 2 years (r(2) = 0.65), possibly demonstrating its continued value as a biomonitor to reflect ambient fall-out levels. In contrast, those of Dirinaria applanata were not correlated with the air dose rate in either year.
113

Short-term effects of particulate matter pollutants on population health: time series studies on emergency hospital admissions. / 顆粒污染物對人群健康的短期效應 : 時間序列研究 / CUHK electronic theses & dissertations collection / Ke li wu ran wu dui ren qun jian kang de duan qi xiao ying : shi jian xu lie yan jiu / Short-term effects of particulate matter pollutants on population health: time series studies on emergency hospital admissions.

January 2012 (has links)
研究背景:顆性空氣污染物(PM₁₀)的危害作用已經為許多病學研究所證實。有學者認為,空氣動學直徑小於2.5 微米的細顆(PM₂.₅)和空氣動學直徑介於2.5 和10 微米之間的粗顆(PMc)屬於種同的污染物,應當分別測。區分粗、細顆的健康效應將為今後分別制訂有關粗、細顆的空氣質標準提供依據。同時,空氣污染物是由顆污染物和氣態污染物構成的複雜混合物,二者之間存在一定程上的合或交互作用。 / 研究目的:以每天心血管系統、呼吸系統疾病急性入院人為研究結局,區別估計顆污染物PM₁₀ 中粗、細顆的健康危害作用,并探討PM₁₀與氣態污染物(二氧化氮,NO₂;二氧化,SO₂;臭氧,O₃)的交互作用。 / 研究方法:收集香港1998 1 月至2007 12 月每天心腦血管疾病、呼吸系統疾病急性入院人,日均污染物濃,日均氣溫、相對濕等資,採用時間序分析的研究方法,應用Poisson 廣義相加模型分析顆污染物中粗、細顆的同健康效應。同時應用三個平的時間序研究模型(雙變反應面模型、合效應模型和分層模型)探討顆污染物和氣態污染物之間潛在的交互作用。 / 研究結果:研究發現,在校正PM₂.₅的影響后,PMc 對呼吸系統疾病導致的急性入院作用顯著,但對心腦血管疾病引起的急性入院則無明顯作用。在雙污染物(PMc 和PM₂.₅)模型中,空氣中每一個IQR(四分位間距)的PM[subscript c] 和PM₂.₅濃的增加將使每天急性呼吸系統疾病入院分別增加1.05% (95% CI: 0.19%, 1.91%)和1.81% (95% CI: 0.78%,2.87%),使急性心腦血管疾病入院分別改變 -0.16% (95% CI: -1.07%,0.76%) 和1.86% (95% CI: 0.85%, 2.88%)。研究發現某種程6 的顆污染物和氣態污染物的交互作用。在NO₂ 或SO₂ 高水平(NO₂ 濃高於64.4μg/m³ 或 SO₂ 濃高於20.9μg/m³)的日子,PM₁₀ 對急性心臟疾病入院的影響高於NO₂ 或SO₂ 低、中水平的日子;而在臭氧高水平(O₃濃高於46.8μg/m³)的日子,PM₁₀ 對急性呼吸和循環系統疾病入院的作用低於O₃ 中、低水平的日子。 / 研究結:粗、細顆污染物對呼吸系統疾病的危害均作用顯著且相對獨,但對循環系統疾病的危害作用則主要體現於細顆污染物。同時,顆性污染物的健康危害可能被空氣中的氣態污染物水平所修飾:研究發現PM₁₀ 與NO₂ 或SO₂ 之間的協同作用,以及PM₁₀ 與O₃ 之間的拮抗作用。 / BACKGROUND: The adverse effects of particulate matter (PM) air pollution have been confirmed by many epidemiological studies. Fine and coarse particles should be considered as separate classes of pollutants and measured separately. Differentiating the effects of fine (PM₂.₅, particles with an aerodynamic diameter less than 2.5 microns) and coarse particles (PM[subscript c], particles with an aerodynamic diameter between 2.5 and 10 microns) would help in the future to support a PM[subscript c] standard. Meanwhile, ambient air pollution is a complex mixture of PM and gaseous pollutants. PM might interact with gaseous pollutants to affect the population health. / STUDY OBJECTIVES: To differentiate the effects of fine and coarse fractions of PM₁₀ and to explore the possible interaction between PM₁₀ and gaseous pollutants (nitrogen dioxide, NO₂; sulfur dioxide, SO₂; ozone, O₃) on emergency hospital admissions for cardio-respiratory diseases in Hong Kong. / METHODS: This is a time series study. Daily counts of emergency hospital admissions for cardio-respiratory diseases, daily mean air pollution concentrations and weather conditions were collected from January 1998 to December 2007 in Hong Kong. We used generalized additive Poisson model with log link allowing overdispersion and autocorrelation to examine the differential effects of PM₂.₅ and PM[subscript c]. Three parallel time series approaches (bivariate response surface model, joint effect model and parametric stratified model) were used to explore the possible interactions between PM₁₀ and gaseous pollutants. / MAIN RESULTS: The associations between PM[subscript c] and emergency hospital admissions were statistically significant for respiratory diseases but not for circulatory diseases. In two-pollutant (PM₂.₅and PM[subscript c]) model, an interquartile range increase in the 4-day moving average (lag₀₃) concentrations of PM[subscript c] and PM₂.₅ corresponded to 1.05% (95% CI: 0.19%, 1.91%) and 1.81% (95% CI: 0.76%, 2.87%) increase of respiratory admissions, respectively. The effect estimates of PM₂.₅and PM[subscript c] remained robust when adjusting for gaseous pollutants. Meanwhile, an interquartile range increase in lag₀₁ concentrations of PM[subscript c] and PM₂.₅was associated with -0.16% (95% CI: -1.07%, 0.76%) and 1.86% (95% CI: 0.85%, 2.88%) change of circulatory admissions, respectively. Some interactions between PM₁₀ and gaseous pollutants were found. The effects of PM₁₀ on circulatory hospitalizations were greatest during the days when NO₂ or SO₂ concentrations were high (the 3rd tertile, NO₂>64.4 or SO₂>20.9μg/m³). The effects of PM₁₀ on both respiratory and circulatory admissions were greatest during the days when O₃ concentrations were in low to medium levels (<=46.8μg/m³). / CONCLUSION: We found PM[subscript c] to be associated with emergency hospital admissions for respiratory diseases independent of the effect of PM₂.₅, but not for circulatory diseases in Hong Kong. The effects of PM₁₀ on cardio-respiratory hospital admissions were modified by gaseous pollutants. There were synergetic interactions between PM₁₀ and NO₂ or SO₂ on cardiac hospitalizations and antagonistic interactions between PM₁₀ and ozone on cardio-respiratory hospitalizations. These findings provide supportive evidence for a future PM[subscript c] regulation and contribute to the development of a multipollutant air quality management. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Qiu, Hong = 顆粒污染物對人群健康的短期效應 : 時間序列研究 / 邱宏. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 122-137). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Qiu, Hong = Ke li wu ran wu dui ren qun jian kang de duan qi xiao ying : shi jian xu lie yan jiu / Qiu Hong. / Abstract (English) --- p.v / Abstract (Chinese) --- p.viii / List of Contents --- p.x / List of Tables --- p.xiv / List of Figures --- p.xvi / List of Abbreviation --- p.xviii / Acknowledgements --- p.xix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Literature Review --- p.5 / Chapter 2.1. --- Review on the differential health effects of fine and coarse particles --- p.5 / Chapter 2.1.1 --- A brief description of particulate matter air pollution --- p.5 / Chapter 2.1.2 --- The objective of this part of literature review --- p.7 / Chapter 2.1.3 --- Methods --- p.8 / Chapter 2.1.3.1 --- Inclusion and exclusion criteria of studies/papers --- p.8 / Chapter 2.1.3.2 --- Search terms and keywords --- p.9 / Chapter 2.1.3.3 --- Information abstracted --- p.9 / Chapter 2.1.4 --- Results --- p.10 / Chapter 2.1.4.1 --- Short-term effects of PM₂.₅and PM[subscript c] on mortality --- p.10 / Chapter 2.1.4.2 --- Short-term effects of PM₂.₅and PM[subscript c] on morbidity --- p.14 / Chapter 2.1.4.3 --- Biological mechanisms underlying the differential effects of PM₂.₅and PM[subscript c] --- p.18 / Chapter 2.1.5 --- Conclusion remarks --- p.19 / Chapter 2.1.5.1 --- Health effects of PM₂.₅and PM[subscript c] on mortality --- p.19 / Chapter 2.1.5.2 --- Health effects of PM₂.₅and PM[subscript c] on morbidity --- p.20 / Chapter 2.2. --- Review on the joint effects/interactions of particulate matter and gaseous pollutants --- p.21 / Chapter 2.2.1 --- Concept of Interaction --- p.21 / Chapter 2.2.2 --- The objective of this part of literature review --- p.21 / Chapter 2.2.3 --- Methods --- p.22 / Chapter 2.2.3.1 --- Search terms and key words --- p.22 / Chapter 2.2.3.2 --- Information abstract --- p.22 / Chapter 2.2.4 --- Results --- p.23 / Chapter 2.2.4.1 --- Studies on the interaction between particulate matter and gaseous pollutants --- p.23 / Chapter 2.2.4.1.1 --- Studies on the interaction between PM₁₀ and NO₂ --- p.23 / Chapter 2.2.4.1.2 --- Studies on the interaction between PM₁₀ and O₃ --- p.24 / Chapter 2.2.4.1.3 --- Studies on the interaction between PM and SO₂ --- p.26 / Chapter 2.2.4.1.4 --- Modifiers identified through multicity study --- p.30 / Chapter 2.2.4.2 --- Methodology used to detect interaction in time series studies --- p.33 / Chapter 2.2.4.2.1 --- Nonparametric bivariable response surface model --- p.33 / Chapter 2.2.4.2.2 --- Non-stratification interaction model --- p.34 / Chapter 2.2.4.2.3 --- Parametric stratified model --- p.34 / Chapter 2.2.4.2.4 --- Time series classification and regression tree (CART) model --- p.35 / Chapter 2.2.4.3 --- Biological mechanisms of interaction between pollutants --- p.36 / Chapter 2.2.5 --- Conclusion remarks --- p.38 / Chapter Chapter 3 --- Differential health effects of fine and coarse particles --- p.39 / Chapter 3.1 --- Objectives --- p.39 / Chapter 3.2 --- Materials and Methods --- p.39 / Chapter 3.2.1 --- Data on particulate pollutants and meteorology variables --- p.39 / Chapter 3.2.2 --- Data on emergency hospital admissions for cardio-respiratory diseases --- p.40 / Chapter 3.2.3 --- Statistical models --- p.42 / Chapter 3.2.3.1 --- Core model set up --- p.42 / Chapter 3.2.3.2 --- Single-pollutant and two-pollutant models --- p.44 / Chapter 3.2.3.3 --- Concentration-response relationship --- p.45 / Chapter 3.2.3.4 --- Sensitivity analysis --- p.46 / Chapter 3.3 --- Results --- p.47 / Chapter 3.3.1 --- Location of Tsuen Wan station, Tsuen Wan region --- p.47 / Chapter 3.3.2 --- Air pollution concentrations and meteorological factors --- p.47 / Chapter 3.3.3 --- Emergency hospital admissions for cardio-respiratory diseases --- p.50 / Chapter 3.3.4 --- Regression results and Sensitivity analysis --- p.51 / Chapter 3.3.4.1 --- Effects of coarse particulate matter on emergency hospital admissions for respiratory diseases --- p.51 / Chapter 3.3.4.2 --- Differential effects of fine and coarse particles on emergency hospital admissions for cardiovascular diseases --- p.56 / Chapter 3.4 --- Discussion --- p.61 / Chapter 3.4.1 --- Main findings of this study --- p.61 / Chapter 3.4.2 --- Compared with findings from the literature --- p.62 / Chapter 3.4.3 --- Exposure windows selection and possible misclassification --- p.64 / Chapter 3.4.4 --- Sensitivity analyses of main findings --- p.65 / Chapter 3.4.5 --- Biological mechanisms of the differential effects of fine and coarse particles --- p.67 / Chapter 3.4.6 --- Limitations of this study --- p.68 / Chapter 3.5 --- Conclusion and recommendations --- p.69 / Chapter Chapter 4 --- Joint effects/Interactions of PM₁₀ and gaseous pollutants --- p.70 / Chapter 4.1 --- Objectives --- p.70 / Chapter 4.2 --- Materials and Methods --- p.70 / Chapter 4.2.1 --- Data on air pollution and meteorology variables --- p.70 / Chapter 4.2.2 --- Data on emergency hospital admissions for cardio-respiratory diseases --- p.71 / Chapter 4.2.3 --- Statistical models --- p.72 / Chapter 4.2.3.1 --- Core model set up --- p.72 / Chapter 4.2.3.2 --- Three parallel time series models --- p.73 / Chapter 4.3 --- Results --- p.76 / Chapter 4.3.1 --- Air pollution concentrations and meteorological factors --- p.76 / Chapter 4.3.2 --- Emergency hospital admissions for cardio-respiratory diseases --- p.79 / Chapter 4.3.3 --- Results from single-pollutant model --- p.81 / Chapter 4.3.3.1 --- Pollution effects on emergency hospital admissions for respiratory diseases --- p.81 / Chapter 4.3.3.2 --- Pollution effects on emergency hospital admissions for circulatory diseases --- p.83 / Chapter 4.3.4 --- Joint effects/Interactions between PM₁₀ and NO₂ on cardio-respiratory hospitalizations --- p.85 / Chapter 4.3.5 --- Joint effects/Interactions between PM₁₀ and O₃ on cardio-respiratory hospitalizations --- p.91 / Chapter 4.3.6 --- Joint effects/Interactions between PM₁₀ and SO₂ on cardio-respiratory hospitalizations --- p.96 / Chapter 4.4 --- Discussion --- p.102 / Chapter 4.4.1 --- Main findings --- p.102 / Chapter 4.4.1.1 --- Effect estimates compared with previous Hong Kong studies --- p.102 / Chapter 4.4.1.2 --- Interactions between particulate matter and gaseous pollutants --- p.103 / Chapter 4.4.1.2.1 --- Interactions between PM₁₀ and NO₂ on cardiac hospitalizations --- p.103 / Chapter 4.4.1.2.2 --- Interactions between PM₁₀ and O₃ on cardio-respiratory hospitalizations --- p.109 / Chapter 4.4.1.2.3 --- Interactions between PM₁₀ and SO₂ on cardiac hospitalizations --- p.113 / Chapter 4.4.2 --- Strengths and limitations of this study --- p.116 / Chapter 4.5 --- Conclusion and recommendations --- p.119 / Chapter Chapter 5 --- Concluding remarks --- p.120 / References List --- p.122 / Chapter Appendix --- Relevant Publications and Submitted/Drafted Papers --- p.138
114

A life cycle assessment on liquid biofuel use in the transport sector of Ethiopia

Dereje Kebede Abebe 02 October 2013 (has links)
Seed-oil based biodiesel production particularly biodiesel production from the nonedible oil seed bearing plant - Jatropha curcas L. - is a key strategic direction outlined in the biofuels strategy of the Government of Ethiopia. The main objective underlying the strategy include substitution of imported diesel oil used in the road transport sector while at the same time contributing to the local and global greenhouse gasses (GHG) reduction efforts. In this study the environmental benefits and costs of production and use of Jatropha biodiesel in the road transport sector of Ethiopia is assessed using a life cycle analysis (LCA) methodology. The analysis focused on determining the potential environmental impacts and net non-renewable energy saving potential of biodiesel from Jatropha oil-seeds using the following metrics: (i) Net Greenhouse Gas (GHG) reduction, and (ii) Net Energy Balance (NEB) relative to diesel oil. The study shows that the net GHG emissions reduction potential of Jatropha Methyl Ester (JME) is highly influenced by the magnitude of initial carbon loss occurring in the process of conversion of different land uses to Jatropha plantation, and less so on other unit processes of JME production system analysed. The NEB of JME relative to use of diesel oil per functional unit of one GJ is less sensitive to impacts of land use change and is generally positive. Where no land use change impacts is considered, or where Jatropha is grown on lands with low carbon stock such as grasslands, substitution of diesel oil with JME in Ethiopia can provide GHG emission reduction of about 43%, and for each MJ of JME produced the nonrenewable energy requirement will be 0,38 MJ. Production of JME by converting lands with high above ground, below ground and/or soil carbon stocks such as shrub lands or well stocked forest lands will result in net loss of carbon and require ecological carbon payback time of 50 to hundreds of years. The impact of introducing and use of JME-diesel oil blends by Anbassa City Bus Services Enterprise (ACBSE) bus fleets shows that, displacement of diesel oil with JME that have positive GHG reduction potential, will also contribute to the reduction of air pollutants and improvement of ambient air quality in Addis Ababa. Two key recommendations of this research work are that to ensure environmental sustainability of biodiesel production from Jatropha seeds (i) land availability and land suitability assessment for estimating the potential available land for Jatropha (and other oil-seed bearing plants) shall be conducted, and (ii) minimum requirements on GHG reduction and NEB requirements on biodiesel shall be established. / Environmental Sciences / M. Sc. (Environmental Management)
115

Particulate allergens potentiate allergic asthma in mice through sustained IgE-mediated mast cell activation.

Jin, C, Shelburne, CP, Li, G, Potts, EN, Riebe, KJ, Sempowski, GD, Foster, WM, Abraham, SN 03 1900 (has links)
Allergic asthma is characterized by airway hyperresponsiveness, inflammation, and a cellular infiltrate dominated by eosinophils. Numerous epidemiological studies have related the exacerbation of allergic asthma with an increase in ambient inhalable particulate matter from air pollutants. This is because inhalable particles efficiently deliver airborne allergens deep into the airways, where they can aggravate allergic asthma symptoms. However, the cellular mechanisms by which inhalable particulate allergens (pAgs) potentiate asthmatic symptoms remain unknown, in part because most in vivo and in vitro studies exploring the pathogenesis of allergic asthma use soluble allergens (sAgs). Using a mouse model of allergic asthma, we found that, compared with their sAg counterparts, pAgs triggered markedly heightened airway hyperresponsiveness and pulmonary eosinophilia in allergen-sensitized mice. Mast cells (MCs) were implicated in this divergent response, as the differences in airway inflammatory responses provoked by the physical nature of the allergens were attenuated in MC-deficient mice. The pAgs were found to mediate MC-dependent responses by enhancing retention of pAg/IgE/FcεRI complexes within lipid raft–enriched, CD63(+) endocytic compartments, which prolonged IgE/FcεRI-initiated signaling and resulted in heightened cytokine responses. These results reveal how the physical attributes of allergens can co-opt MC endocytic circuitry and signaling responses to aggravate pathological responses of allergic asthma in mice. / Dissertation
116

Hierarquização das áreas de concentração de emissão de poluentes decorrentes do transporte de carga em São Paulo utilizando técnicas de geoprocessamento. / Ranking of areas of concentration of pollution arising from issuance of cargo transport in São Paulo using geoprocessing techniques.

Lage, Mariana de Oliveira 27 April 2016 (has links)
O presente estudo agrega os dados geoespaciais livres, cedidos pela prefeitura de São Paulo, IBGE, CNAE, RAIS, entre outros e particulares, cedidos pela empresa Maplink, com os recursos dos Sistemas de Informações Geográficas - SIG, para planejamento de Transportes. A megacidade de São Paulo com mais de dez milhões de habitantes tem milhares de estabelecimentos comerciais para atender a demanda dessa população, que precisa ser abastecidos. Os veículos de carga que abastecem, além de afetarem o trânsito e mobilidade urbana, emitem poluentes. O objetivo é hierarquizar as áreas da megacidade de São Paulo (Brasil) com características potenciais para alta concentração de poluentes decorrentes da circulação dos veículos de carga para abastecer os estabelecimentos comerciais. A metodologia correlaciona espacialmente os dois conjuntos de dados (localização de estabelecimentos comerciais e a circulação de veículos de transporte de cargas) utilizando ferramentas de análises espaciais, baseada em Kernel Density Estimator - KDE, a análise de multicritério, como a Analytic Hierarchy Process - AHP para avaliar como estes duas variáveis estão relacionadas, e também a lógica Fuzzy para calcular esses dados. Os resultados obtidos demonstra que as avenidas e rodovias do município de São Paulo possuem alta concentração de poluentes, sendo utilizadas como rotas para os veículos de carga que tanto fazem do município sua origem e/ou destino, as regiões que possuem alta concentração de poluentes atmosféricos são: Cerqueira César, Parque Dom Pedro II e Ibirapuera, com destaque também na Marginal Tietê e Marginal Pinheiros, além da zona leste (Itaquera e Itaim Paulista). / This study adds free geospatial data, granted by the city of São Paulo, IBGE, CNAE, RAIS, among others and individuals assigned by Maplink company with the capabilities of Geographic Information Systems - GIS for Transportation planning. The megacity of São Paulo with more than ten million inhabitants has thousands of shops to meet the needs of this population, which must be supplied. The cargo vehicles that supply, as well as affect the traffic and urban mobility, emit pollutants. The goal is to prioritize areas of the megacity of São Paulo (Brazil) with potential characteristics for high concentration of pollutants resulting from the movement of cargo vehicles to supply shops. The methodology spatially correlate the two sets of data (location of commercial establishments and the movement of cargo transport vehicles) using tools of spatial analysis based on Kernel Density Estimator - KDE, the multi-criteria analysis, as the Analytic Hierarchy Process - AHP to evaluate how these two variables are related, and also fuzzy logic to calculate this data. The results show that the avenues and highways of São Paulo have a high concentration of pollutants, being used as routes for freight vehicles that both make the city their origin and / or destination, the regions with high concentration of air pollutants they are: Cerqueira Cesar, Parque Dom Pedro II and Ibirapuera, highlighting also the Marginal Tiete and Pinheiros, besides the east side (Itaquera and Itaim Paulista).
117

Avaliação da influência de fatores ambientais sobre o diagnóstico de artrite idiopática juvenil em crianças e adolescentes / Evaluation of the influence of environmental factors on the juvenile idiopathic arthritis in children and adolescents

França, Camila Maria Paiva 14 March 2017 (has links)
A artrite idiopática juvenil (AIJ) constitui um grupo heterogêneo de doenças que se caracteriza por inflamação crônica em uma ou mais articulações, com diagnóstico em menores de 16 anos de idade. A poluição atmosférica tem sido responsabilizada pelo aumento da morbidade e mortalidade em doenças cardiorrespiratórias, mas poucos estudos avaliaram os efeitos da exposição prolongada sobre doenças inflamatórias crônicas. Alguns estudos demonstram associação entre fumo e início da doença reumatológica em adultos e outros mostram associação de mães fumantes durante a gravidez com desenvolvimento de AIJ nos filhos. Entretanto, existem poucos estudos na literatura avaliando a exposição à poluição do ar e AIJ. Objetivo: avaliar a influência de poluentes ambientais inalatórios como fatores de risco no desenvolvimento da AIJ em pacientes residentes na Região Metropolitana de São Paulo, acompanhados em um serviço terciário de Reumatologia Pediátrica. Metodologia: Este foi um estudo retrospectivo, do tipo caso-controle, que incluiu 66 pacientes com AIJ e 124 controles saudáveis, semelhantes em idade e gênero, residentes na Região Metropolitana de São Paulo, desde a gestação até o diagnóstico da doença. Um questionário estruturado e com alto índice de confiabilidade (índice kappa para teste-reteste 0,80) avaliou dados demográficos, fatores relacionados à gestação e ao período perinatal, exposição ocupacional materna durante a gravidez a partículas inaláveis e/ou vapor volátil, exposição ao tabaco e exposição à inalação ambiental durante a gravidez e após o nascimento (presença de atividades industriais, pedreiras ou postos de gasolina perto do domiícilio/ trabalho/ creche/ escola). Foram também analisados poluentes troposféricos nos dois períodos: material particulado (PM10), dióxido de enxofre (SO2), dióxido de nitrogênio (NO2), ozônio (O3) e monóxido de carbono (CO). Resultados: Durante a gravidez, o fumo fetal (OR= 3,43, IC 95%: 1,45-8,12, p=0,005) e a exposição ocupacional materna (OR= 13,69, IC95%: 4,43-42,27, p < 0,001) se mostraram fatores de risco independentes para AIJ. Em contrapartida, o fato de a mãe trabalhar fora de casa (OR= 0,06, IC 95%: 0,02- 0,16, p < 0,001) e o ganho de peso ideal da mãe (OR = 0,36, IC 95%: 0,16-0,83, p= 0,017) apresentaram associação negativa. Para o período após o nascimento até o diagnóstico de AIJ, fumo passivo (OR= 3,6, IC 95%: 1,76- 7,31, p < 0,0001) e exposição ao ozônio durante o segundo ano de idade (OR= 2,76, IC 95%: 1,20-6,37, p= 0,017) foram fatores de risco independentes e significativos para o diagnóstico da AIJ. Conclusão: O fumo passivo, a exposição ao ozônio no segundo ano de vida e a exposição ocupacional materna são destacados como importantes fatores de risco para a AIJ / Juvenile idiopathic arthritis (JIA) is a heterogeneous group of diseases characterized by chronic inflammation in one or more joints with onset in children under 16 years of age. Air pollution has been blamed for increased morbidity and mortality in cardiorespiratory diseases, but few studies have evaluated the effects of prolonged exposure on chronic inflammatory diseases. Some studies show an association between smoking and onset of rheumatologic illness in adults, and others show an association of smoking mothers during pregnancy with the development of JIA in children. However, there are few studies in the literature to date evaluating exposure to air pollution and JIA. Objective: To evaluate the influence of exposure to inhalable environmental factors during pregnancy and after birth until JIA diagnosis in residents of the São Paulo metropolitan area. Methods: Case-control study comprising 66 JIA patients and 124 healthy controls matched by age and gender, living in the Sao Paulo metropolitan area until JIA diagnosis, and whose mothers had resided in this region during pregnancy. A structured and reliable questionnaire (kappa index for test-retest was 0.80) assessed demographic data, gestational and perinatal-related factors, mothers\' work-related exposure during pregnancy to inhalable particles and / or volatile vapor, exposure to inhalable elements during pregnancy and after birth (work-related exposure to inhalable particles and/or volatile vapor, exposure to tobacco and the presence of industrial activities, quarries or gas stations near the home/ work/ daycare/ school). Tropospheric pollutants included: particulate matter (PM10), sulphur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3) and carbon monoxide (CO). Results: During pregnancy, fetal smoking (OR=3.43, 95%CI: 1.45-8.12, p=0.005) and mothers\' work-related exposure (OR=13.69, 95%CI: 4.43-42.27, p < 0.001) were independent significant risk factors for JIA diagnosis. In contrast, working mother (OR=0.06, 95% IC: 0.02-0.16, p < 0.001) and ideal mother weight gain (OR=0.36, 95% IC:0.16-0.83, p=0.017) presented a negative association. After birth until JIA diagnosis, secondhand smoking (OR=3.6, 95% IC: 1.76-7.31, p < 0.0001) and exposure to O3 during the second year of age (OR=2.76, 95% IC: 1.20-6.37, p=0.017) were independent and significant risk factors for JIA diagnosis. Conclusion: Secondhand smoking, exposure to O3 during the second year of age and mothers\' work-related exposure are highlighted as important risk factors to JIA
118

Efeito da talidomida na expressão e síntese dos proteoheparans sulfato de superfície celular em linhagens de mieloma múltiplo / Effects of sugar cane burning emissions on the ocular surface

Matsuda, Monique 10 February 2006 (has links)
Efeitos adversos das emissões geradas pela queim a da cana de açúcar representa um problema que afeta principalmente os países em desenvolvimento. Estudos prévios têm demonstrado que, durante o período de queima, há um aumento das admissões hospitalares e atendimentos de emergência nas cidades do Brasil próximas às plantações de cana. Entretanto, até o momento, não há estudos que avaliaram os efeitos sobre a superfície ocular. O presente trabalho avalia o impacto causado pela queima da cana sobre a superfície ocular e cortadores de cana e na população da região de Tatuí SP. Vinte e dois cortadores de cana e dezenove voluntários do perímetro urbano de Tatuí SP, localizada no Estado de São Paulo, fora recrutados para o estudo. Medidas ambientais das concentrações de aterial particulado de 2,5 (MP2,5), temperatura e umidade fora ensuradas durante os períodos de queima e entresafra. Ao esmo tempo, avaliações histológicas e clínicas da superfície ocular, tais como, citologia de impressão da região tarsal, tempo de rotura do filme lacrimal (TRFL), teste de Schirmer I, colorações vitais por rosa bengala e fluoresceína, bio microscopia e sintomas oculares foram realizadas durante os dois períodos. Níveis de MP2,5 durante a atividade de corte da cana queimada foi 3,5 vezes mais elevados do que o limite de 25 g/3 sugerido pelo órgão de regulamentação.Nas avaliações oculares, observa os que os valores médios das áreas coradas por ácido periódico de Schiff (PAS) das amostras dos cortadores fora menores durante o período de queima (57 ±6,8%) do que na entresafra (64,3 ±12%; p=0,014) e quando comparadas com as amostras dos voluntários da cidade (63,9 ±6.8%;p=0,009). Modelo de regressão não linear revela uma forte associação entre os valores médios das áreas PAS positivas e os anos de trabalho no corte da cana queimada. Detectamos um aumento nas áreas PAS positivas conforme os anos de trabalho acumulados no corte da cana queimada durante o período da entresafra (r=0,99;p=0,015).Teste de Schirmer I revela uma diminuição dos valores conforme e os anos de trabalho no corte da cana queimada observados durante o período de quei a.(r=0,99;p=0,026).Valores médios de TRFL dos cortadores de cana durante o periodo de queima (6,48 ±3.47s) fora menores do que na entresafra (10,16 ±7,79) e quando comparadas como TRFL dos voluntários da cidade (8,6 ±4,6s;p<0,05).Não houve diferenças estatísticas e relação às outras variáveis oculares. Nossos resultados sugere que a exposição sazonal às altas concentrações das emissões geradas pela queima da cana de açúcar pode causar efeitos tóxicos sobre a mucosa epitelial e afetar a estabilidade do filme lacrimal, permitindo que o epitélio torne se enos protegido aos agentes deletérios. Por outro lado,a exposição crônica às emissões da cana parece induzir uma resposta adaptativa do epitélio ocular, associado a umaumento da densidade de muco para compensar a perda de células caliciformes durante o período da queima, todos os anos. E conclusão, esses achados reforça a i portância de futuras investigações para melhor compreender as consequências da poluição at osférica sobre a superfície ocular e sugere edidas para proteção da superfície ocular durante este período. / The adverse effects of particle emissions produced by sugar cane burning represent a proble that affects ostly developing countries. Previous studies have shown that, during the burning period, there is an increase in respiratory hospital admissions and emergency room visits in communities surrounded by sugar cane plantations in rural cities of Brazil. However, until this date, nom previous studies have evaluated the effects on the ocular surface. The ai of the present work is to study the impact of the sugar cane burning on the ocular surface of cane workers and the people at the city of Tatuí, near the burning crops. Twenty two healthy sugar cane workers and nineteen volunteers fro Tatuí region located at the State of Sao Paulo, Brazil, were recruited to the study. Measure ents of the average concentrations of particulate atter 2.5um, temperature and humidity were done during the burning and non burning periods. Concurrently, histological and clinical assessments of the ocular surface such as, inferior tarsal impression cytology, tear film break-up time, Schirmer´s I test, fluorescein and rose bengal staining, biomicroscopy and eye irritation symptoms were evaluated during the two periods. PM2.5 exposure levels in the crops during the activity of burnt cane cutting were 3.5 fold higher than the suggest limit of 25ug/m3 proposed by governmental regulation. On ocular assessments, we observed that the average of periodic acid Schiff (PAS)positive areas of sugar cane workers samples were lower during the burning (mean 57%,SD 6.8) than the non burning period (mean 64.3%,SD 12;p=0.014) and the downtown volunteers samples (mean 63.9%,SD 6.8;p=0.009). A non linear regression model reveals a strong relationship between average PAS positive areas and years working in sugar cane harvesting. We noticed an increase in PAS positive areas as long as the years accumulated in sugar cane harvesting labor during non burning period (r=0.99,p=0.015). Schirmer test t reveals impairment at the values across the years of labour in sugar cane harvesting observed during the burning period (r=0.99,p=0.026). Mean TBUT values of sugar cane workers during the burning period (mean 6.48s; SD 3.47)were lower than non burning period (mean 10.16s;SD 7.79) and than TBUT of the volunteers of downtown (mean 8.6s,SD 4.6;p<0.05). There were no statistically differences among the groups for the other ocular variables. Our results suggest that seasonal exposition of higher concentrations of emissions generated by sugar cane burning ay cause toxic effects on the mucosal epithelium and affect tear film stability that ay leave underlying ocular epithelium less protected to har ful agents. On the other hand, chronic occupational exposure to sugar cane emissions during harvest ay induce an adaptive response of ocular epithelium associated with an increase of mucus density in order to compensate loss of goblet cells every year during burning period. In conclusion, these findings reinforce the importance for further investigations to better understanding the consequences of air pollution on the ocular surface and suggest procedures to protect ocular surface during this period.
119

Efeitos das emissões geradas pela queima dos canaviais sobre a superfície ocular / Effects of sugar cane burning emissions on the ocular surface

Matsuda, Monique 26 February 2010 (has links)
Efeitos adversos das emissões geradas pela queima da cana-de-açúcar representa um problema que afeta principalmente os países em desenvolvimento. Estudos prévios têm demonstrado que, durante o período de queima, há um aumento das admissões hospitalares e atendimentos de emergência nas cidades do Brasil próximas às plantações de cana. Entretanto, até o momento, não há estudos que avaliaram os efeitos sobre a superfície ocular. O presente trabalho avalia o impacto causado pela queima da cana sobre a superfície ocular em cortadores de cana e na população da região de Tatuí-SP. Vinte e dois cortadores de cana e dezenove voluntários do perímetro urbano de Tatuí-SP, localizada no Estado de São Paulo, foram recrutados para o estudo. Medidas ambientais das concentrações de material particulado de 2,5 Vm (MP2,5), temperatura e umidade foram mensuradas durante os períodos de queima e entresafra. Ao mesmo tempo, avaliações histológicas e clínicas da superfície ocular, tais como, citologia de impressão da região tarsal, tempo de rotura do filme lacrimal (TRFL), teste de Schirmer I, colorações vitais por rosa bengala e fluoresceína, biomicroscopia e sintomas oculares foram realizadas durante os dois períodos. Níveis de MP2,5 durante a atividade de corte da cana queimada foi 3,5 vezes mais elevados do que o limite de 25Vg/m3 sugerido pelo órgão de regulamentação. Nas avaliações oculares, observamos que os valores médios das áreas coradas por ácido periódico de Schiff (PAS) das amostras dos cortadores foram menores durante o período de queima (57±6,8%) do que na entresafra (64,3±12%; p=0,014) e quando comparadas com as amostras dos voluntários da cidade (63,9±6.8%; p=0,009). Modelo de regressão não-linear revela uma forte associação entre os valores médios das áreas PAS positivas e os anos de trabalho no corte da cana queimada. Detectamos um aumento nas áreas PAS positivas conforme os anos de trabalho acumulados no corte da cana queimada durante o período da entresafra (r=0,99; p=0,015). Teste de Schirmer I revela uma diminuição dos valores conforme os anos de trabalho no corte da cana queimada observados durante o período de queima. (r=0,99; p=0,026). Valores médios de TRFL dos cortadores de cana durante o periodo de queima (6,48±3.47s) foram menores do que na entresafra (10,16±7,79) e quando comparadas com o TRFL dos voluntários da cidade (8,6±4,6s; p<0,05). Não houve diferenças estatísticas em relação às outras variáveis oculares. Nossos resultados sugerem que a exposição sazonal às altas concentrações das emissões geradas pela queima da cana-de-açúcar pode causar efeitos tóxicos sobre a mucosa epitelial e afetar a estabilidade do filme lacrimal, permitindo que o epitélio torne-se menos protegido aos agentes deletérios. Por outro lado, a exposição crônica às emissões da cana parece induzir uma resposta adaptativa do epitélio ocular, associado a um aumento da densidade de muco para compensar a perda de células caliciformes durante o período da queima, todos os anos. Em conclusão, esses achados reforçam a importância de futuras investigações para melhor compreender as consequências da poluição atmosférica sobre a superfície ocular e sugere medidas para proteção da superfície ocular durante este período. / The adverse effects of particle emissions produced by sugar cane burning represent a problem that affects mostly developing countries. Previous studies have shown that, during the burning period, there is an increase in respiratory hospital admissions and emergency room visits in communities surrounded by sugar cane plantations in rural cities of Brazil. However, until this date, no previous studies have evaluated the effects on the ocular surface. The aim of the present work is to study the impact of the sugar cane burning on the ocular surface of cane workers and the people at the city of Tatuí, near the burning crops. Twenty-two healthy sugar cane workers and nineteen volunteers from Tatuí region located at the State of Sao Paulo, Brazil, were recruited to the study. Measurements of the average concentrations of particulate matter 2.5 Vm, temperature and humidity were done during the burning and non-burning periods. Concurrently, histological and clinical assessments of the ocular surface such as, inferior tarsal impression cytology, tear film break-up time, Schirmer´s I test, fluorescein and rose bengal staining, biomicroscopy and eye irritation symptoms were evaluated during the two periods. PM2.5 exposure levels in the crops during the activity of burnt cane cutting were 3.5-fold higher than the suggest limit of 25Vg/m3 proposed by governmental regulation. On ocular assessments, we observed that the average of periodic acid-Schiff (PAS) positive areas of sugar cane workers samples were lower during the burning (mean 57%, SD 6.8) than the non-burning period (mean 64.3%, SD 12; p=0.014) and the downtown volunteers samples (mean 63.9%, SD 6.8; p=0.009). A non-linear regression model reveals a strong relationship between average PAS positive areas and years working in sugar cane harvesting. We noticed an increase in PAS positive areas as long as the years accumulated in sugar cane harvesting labor during non-burning period (r=0.99, p=0.015). Schirmer test t reveals impairment at the values across the years of labour in sugar cane harvesting observed during the burning period (r=0.99, p=0.026). Mean TBUT values of sugar cane workers during the burning period (mean 6.48s; SD 3.47) were lower than non-burning period (mean 10.16s; SD 7.79) and than TBUT of the volunteers of downtown (mean 8.6s, SD 4.6; p<0.05). There were no statistically differences among the groups for the other ocular variables. Our results suggest that seasonal exposition of higher concentrations of emissions generated by sugar cane burning may cause toxic effects on the mucosal epithelium and affect tear film stability that may leave underlying ocular epithelium less protected to harmful agents. On the other hand, chronic occupational exposure to sugar cane emissions during harvest may induce an adaptive response of ocular epithelium associated with an increase of mucus density in order to compensate loss of goblet cells every year during burning period. In conclusion, these findings reinforce the importance for further investigations to better understanding the consequences of air pollution on the ocular surface and suggest procedures to protect ocular surface during this period.
120

Prevalência de asma e rinite em escolares expostos às emissões da queima de cana de açúcar

Riguera, Denise 23 July 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:25Z (GMT). No. of bitstreams: 1 deniserigueira_dissertr.pdf: 813199 bytes, checksum: 6d0fe389f5316c7bbac1ab5ea9588a7a (MD5) Previous issue date: 2010-07-23 / Respiratory diseases are the second most frequent cause of hospitalization by the Brazilian Unified Health System (SUS). SUS is responsible for 1,541,113 admissions throughout the country. Asthma and Rhinitis are considered the most common chronic diseases among children and teenagers. Their prevalence has been significantly increased becoming a major public health problem. There is a wide range variation in prevalence of reported asthma, rhinitis, and their symptoms. The observed differences can be, at least in part, due to methodological problems in defining asthma symptoms. The International Study of Asthma and Allergies in Childhood (ISAAC) was developed in an attempt to standardize the methods used in epidemiological studies. It is used to evaluate and compare the prevalence and severity of asthma, rhinitis, and eczema among different cities and countries. In Brazil, the standardized ISAAC questionnaire was translated and validated. Several studies pinpoint that social and environmental factors such as the Western lifestyle, urbanization, and increased population density can be considered as important determinants in the prevalence of asthma and rhinitis. Air pollution has also been identified as an exacerbating factor of these allergic diseases. More recent studies have shown the association between air pollution due to cane trash burning and respiratory morbidity, thus increasing the amount of daily inhalation at the Emergency Service and hospitalizations due to respiratory problems. Objective: To estimate prevalence of asthma, rhinitis, related respiratory symptoms, and predisposing factors in students from Monte Aprazível, São Paulo State, and to evaluate the role of daily exposition to air pollution on respiratory function of these students. Monte Aprazível is a low-population density city, with low motor traffic; warm climate; and a predominantly sugarcane-based agriculture. Casuistry and Method: This is a descriptive transversal study in children ranging from 10-14 years of age, using a questionnaire composed of asthma and rhinitis components of ISAAC protocol, along with socio-demographic and predisposing factor questions, family and personal past medical history. Repeated measures of peak expiratory flow in children, and black carbon and PM2,5 concentration levels were carried out. Results: Prevalence of asthma and rhinitis was 11% and 33.2%, respectively. From the asthmatic children, 10.4% presented four or more wheezing attacks in the past 12 months. Past family history was associated to presence of current asthma and rhinitis. Regarding rhinitis, there was also an association with presence of mold and cracks on the house. Rhinitis was most frequent from June to October, which matches sugarcane harvest season. Daily prevalence of PEF beneath 80% of the median was higher in days with greater concentration of PM2,5. Conclusion: Prevalence of asthma is below national average and that of rhinitis is above. Evidence suggests that pollution levels in cane trash burn season, although within acceptable levels, can be contributing to exacerbation of asthma and rhinitis episodes. / As doenças respiratórias constituem a segunda causa de hospitalização pelo SUS (13,59%), responsabilizando-se por 1.541.113 internações em todo o país. A asma e a rinite são consideradas as doenças crônicas mais comuns entre crianças e adolescentes e com prevalências que têm aumentado significativamente, tornando-se um importante problema de saúde pública. Existe grande variação nas prevalências relatadas de asma, rinite e seus sintomas. As diferenças observadas podem ser, pelo menos em parte, devidas a problemas metodológicos na definição dos sintomas de asma. Na tentativa de padronizar os métodos utilizados em estudos epidemiológicos para estimar e comparar prevalência e gravidade de asma, rinite e eczema entre diferentes cidades e países foi desenvolvido o International Study of Asthma and Allergies in Childhood (ISAAC). No Brasil, seu questionário padronizado foi traduzido e validado para o português. Vários estudos ressaltam que fatores sócio-ambientais como o estilo de vida ocidental, urbanização e elevada densidade populacional podem ser considerados determinantes importantes nas prevalências de asma e rinite. A poluição atmosférica também tem sido identificada como fator exacerbador dessas doenças alérgicas. Estudos mais recentes associam exposição à poluição do ar a aumento na incidência de asma. Diversos estudos têm mostrado associação entre poluição ambiental decorrente de queima de palha da cana de açúcar e morbidade respiratória, com aumento do número diário de inalações no Serviço de Emergência e aumento de internações hospitalares por problemas respiratórios. Objetivo: Estimar a prevalência de asma, rinite, sintomas respiratórios relacionados e fatores predisponentes em escolares de Monte Aprazível-SP, cidade com baixo tráfego, baixa densidade populacional, clima quente e que tem como base agrícola predominante a cana de açúcar, e avaliar o papel da exposição diária de poluição do ar na função respiratória desses escolares. Casuística e Método: Estudo descritivo transversal em crianças de 10 a 14 anos, com aplicação de questionário composto pelos componentes de asma e de rinite do protocolo ISAAC, acrescido de questões sócio-demográficas, fatores predisponentes e antecedentes pessoais e familiares. Foram realizadas medidas repetidas do pico de fluxo expiratório nas crianças e dos níveis de concentração de PM2,5 e de black carbon. Resultados: A prevalência de asma foi de 11% e de rinite, de 33,2%. 10,4% apresentaram mais de 4 crises de sibilos nos últimos 12 meses. Antecedentes familiares se associaram à presença de asma e de rinite atuais. Para rinite, houve também associação com presença de mofo ou rachadura na casa. Rinite apresentou maior frequência nos meses de junho a outubro, período de safra da cana de açúcar. Prevalência diária de PFE abaixo de 80% da mediana foi maior em dias com maior concentração de PM2,5. Conclusão: A prevalência de asma está abaixo e a de rinite está acima da média nacional. As evidências sugerem que os níveis de poluição nos períodos de queima da palha da cana de açúcar, embora dentro dos níveis aceitáveis, podem estar contribuindo para a exacerbação de episódios de asma e de rinite.

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