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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.
171

Exposure of poultry farm workers to ammonia, particulate matter and microorganisms in the Potchefstroom district, South Africa / by A.C. de Jager

De 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.
172

Characterizing the emissions of fine particulate matter in the vicinity of a rail yard

Galvis Remolina, Boris 12 January 2015 (has links)
Aerosol emissions from diesel combustion and other activities in rail yards can affect the health of urban populations. Fine particulate (PM[subscript 2.5]) concentrations near the Inman and Tilford rail yards in Atlanta, Georgia, are the highest measured in the state. The rail yard complex is surrounded by homes, schools, businesses and other industries. The impact of the aerosol emissions from these rail yards on local concentrations of PM[subscript 2.5] was quantified. Specifically, black carbon and PM[subscript 2.5] fuel-based emission factors from the rail yards were estimated by carbon balance using high time-resolution monitoring, a BC and PM[subscript 2.5] emissions inventory was estimated and dispersion modeling was applied to assess the impact of the rail yard activities on local air quality and the cost and benefits of upgrading locomotive engines with cleaner technologies was assessed. Further, baseline information that will allow a later evaluation of the improvement of local air quality as locomotives operating in the rail yards are upgraded was generated, and a composition profile of the rail yard aerosols was developed using chemical speciation techniques. These results found that activities from locomotives in the Inman and Tilford Rail yards lead to and an average emission factor of 6.0 ± 0.5 g of PM[subscript 2.5] per gallon of fuel and are responsible for increases in annual average concentrations of approximately 1.3 µg/m³ of PM[subscript 2.5] as far as 1 km from the perimeter of the rail yard complex. Approximately 11.7 tons of BC and 26 tons of PM[subscript 2.5] per year were emitted from the rail yards in 2011. The rail yards were found to be important sources of hydrocarbon-like organic aerosols (HOA) and black carbon from fuel (BCf). Upgrading the engines at the rail yards would decrease PM[subscript 2.5] emissions by about 9 t/year, reducing PM[subscript 2.5] concentrations around 0.5±0.1 µg/m³ as far as 1 km from the perimeter of the rail yard complex and producing monetized health benefits of approximately 24 million dollars per year.
173

Verursacher und Tendenzen für PM2,5 in Sachsen

Bretschneider, Diana, Schmidt, Wolfram, Düring, Ingo, Lorentz, Helmut 21 February 2012 (has links) (PDF)
Feinstaub kleiner 2,5 Mikrometer (PM2,5) ist ein neuer Parameter zur Beurteilung der Luftqualität. Ziel- und Grenzwerte für PM2,5 wurden mit der Novellierung der EU-Luftqualitätsrichtlinie 2008 zusätzlich zu denen für Feinstaub kleiner 10 Mikrometer (PM10) festgelegt. Die größten sächsischen Quellen für PM2,5 sind Straßenverkehr und Kleinfeuerungsanlagen für feste Brennstoffe. Industrie und Landwirtschaft sind weitere Quellen. Der Anteil von PM2,5 am PM10 ist bei den Jahresmittelwerten stabil. Deshalb können für die Beurteilung der Luftqualität an geringer belasteten Orten auch die bisher gemessenen PM10-Daten mit herangezogen werden. Der ab 2015 geltende Grenzwert für PM2,5 ist in Sachsen bisher nicht überschritten worden. Die erstmals für die ganze Fläche Sachsens modellierte Belastung hat für die Prognosejahre 2015 und 2020 ebenfalls keine Hinweise auf Grenzwertüberschreitungen ergeben. Das nationale Ziel für die Minderung der durchschnittlichen Exposition der Bevölkerung bis 2020 stellt noch einmal höhere Anforderungen an die Luftqualität.
174

Evaluation of interactive effects between temperature and air pollution on health outcomes

Ren, Cizao January 2007 (has links)
A large number of studies have shown that both temperature and air pollution (eg, particulate matter and ozone) are associated with health outcomes. So far, it has received limited attention whether air pollution and temperature interact to affect health outcomes. A few studies have examined interactive effects between temperature and air pollution, but produced conflicting results. This thesis aimed to examine whether air pollution (including ozone and particulate matter) and temperature interacted to affect health outcomes in Brisbane, Australia and 95 large US communities. In order to examine the consistency across different cities and different countries, we used two datasets to examine interactive effects of temperature and air pollution. One dataset was collected in Brisbane City, Australia, during 1996-2000. The dataset included air pollution (PM10, ozone and nitrogen dioxide), weather conditions (minimum temperature, maximum temperature, relative humidity and rainfall) and different health outcomes. Another dataset was collected from the 95 large US communities, which included air pollution (ozone was used in the thesis), weather conditions (maximum temperature and dew point temperature) and mortality (all non-external cause mortality and cardiorespiratory mortality). Firstly, we used three parallel time-series models to examine whether maximum temperature modified PM10 effects on cardiovascular hospital admissions (CHA), respiratory hospital admissions (RHA), cardiovascular emergency visits (CEV), respiratory emergency visits (REV), cardiovascular mortality (CM) and non-external cause mortality (NECM), at lags of 0-2 days in Brisbane. We used a Poisson generalized additive model (GAM) to fit a bivariate model to explore joint response surfaces of both maximum temperature and particulate matter less than 10 μm in diameter (PM10) on individual health outcomes at each lag. Results show that temperature and PM10 interacted to affect different health outcomes at various lags. Then, we separately fitted non-stratification and stratification GAM models to quantify the interactive effects. In the non-stratification model, we examined the interactive effects by including a pointwise product for both temperature and the pollutant. In the stratification model, we categorized temperature into two levels using different cut-offs and then included an interactive term for both pollutant and temperature. Results show that maximum temperature significantly and positively modified the associations of PM10 with RHA, CEV, REV, CM and NECM at various lags, but not for CHA. Then, we used the above Poisson regression models to examine whether PM10 modified the associations of minimum temperature with CHA, RHA, CEV, REV, CM and NECM at lags of 0-2 days. In this part, we categorized PM10 into two levels using the mean as cut-off to fit the stratification model. The results show that PM10 significantly modified the effects of temperature on CHA, RHA, CM and NECM at various lags. The enhanced adverse temperature effects were found at higher levels of PM10, but there was no clear evidence for synergistic effects on CEV and REV at various lags. Three parallel models produced similar results, which strengthened the validity of these findings. Thirdly, we examined whether there were the interactive effects between maximum temperature and ozone on NECM in individual communities between April and October, 1987-2000, using the data of 60 eastern US communities from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS). We divided these communities into two regions (northeast and southeast) according to the NMMAPS study. We first used the bivariate model to examine the joint effects between temperature and ozone on NECM in each community, and then fit a stratification model in each community by categorizing temperature into three levels. After that, we used Bayesian meta-analysis to estimate overall effects across regions and temperature levels from the stratification model. The bivariate model shows that temperature obviously modified ozone effects in most of the northeast communities, but the trend was not obviously in the southeast region. Bayesian meta-analysis shows that in the northeast region, a 10-ppb increment in ozone was associated with 2.2% (95% posterior interval [PI]: 1.2%, 3.1 %), 3.1% (95% PI: 2.2%, 3.8 %) and 6.2 % (95% PI: 4.8%, 7.6 %) increase in mortality for low, moderate and high temperature levels, respectively, while in the southeast region, a 10-ppb increment in ozone was associated with 1.1% (95% PI: -1.1%, 3.2 %), 1.5% (95% PI: 0.2%, 2.8%) and 1.3% (95% PI: -0.3%, 3.0 %) increase in mortality. In addition, we examined whether temperature modified ozone effects on cardiovascular mortality in 95 large US communities between May and October, 1987-2000 using the same models as the above. We divided the communities into 7 regions according to the NMMAPS study (Northeast, Industrial Midwest, Upper Midwest, Northwest, Southeast, Southwest and Southern California). The bivariate model shows that temperature modified ozone effects in most of the communities in the northern regions (Northeast, Industrial Midwest, Upper Midwest, Northwest), but such modification was not obvious in the southern regions (Southeast, Southwest and Southern California). Bayesian meta-analysis shows that temperature significantly modified ozone effects in the Northeast, Industrial Midwest and Northwest regions, but not significant in Upper Midwest, Southeast, Southwest and Southern California. Nationally, temperature marginally positively modified ozone effects on cardiovascular mortality. A 10-ppb increment in ozone was associated with 0.4% (95% posterior interval [PI]: -0.2, 0.9 %), 0.3% (95% PI: -0.3%, 1.0%) and 1.6% (95% PI: 4.8%, 7.6%) increase in mortality for low, moderate and high temperature levels, respectively. The difference of overall effects between high and low temperature levels was 1.3% (95% PI: - 0.4%, 2.9%) in the 95 communities. Finally, we examined whether ozone modified the association between maximum temperature and cardiovascular mortality in 60 large eastern US communities during the warmer days, 1987-2000. The communities were divided into the northeast and southeast regions. We restricted the analyses to the warmer days when temperature was equal to or higher than the median in each community throughout the study period. We fitted a bivariate model to explore the joint effects between temperature and ozone on cardiovascular mortality in individual communities and results show that in general, ozone positively modified the association between temperature and mortality in the northeast region, but such modification was not obvious in the southeast region. Because temperature effects on mortality might partly intermediate by ozone, we divided the dataset into four equal subsets using quartiles as cut-offs. Then, we fitted a parametric model to examine the associations between temperature and mortality across different levels of ozone using the subsets. Results show that the higher the ozone concentrations, the stronger the temperature-mortality associations in the northeast region. However, such a trend was not obvious in the southeast region. Overall, this study found strong evidence that temperature and air pollution interacted to affect health outcomes. PM10 and temperature interacted to affect different health outcomes at various lags in Brisbane, Australia. Temperature and ozone also interacted to affect NECM and CM in US communities and such modification varied considerably across different regions. The symmetric modification between temperature and air pollution was observed in the study. This implies that it is considerably important to evaluate the interactive effect while estimating temperature or air pollution effects and further investigate reasons behind the regional variability.
175

Η ατμοσφαιρική ρύπανση στην Αθήνα

Ανδρεοπούλου, Ευφροσύνη 15 February 2012 (has links)
Η ανάπτυξη των μεγαλουπόλεων συνεπάγεται τεράστιες εκπομπές αιωρούμενων σωματιδίων και άλλων ρυπαντών ουσιών στην ατμόσφαιρα, το οποίο οδηγεί σε πολύ μεγάλη υποβάθμιση της ποιότητας του ατμοσφαιρικού τους αέρα. Η καταγραφή και μελέτη όλων αυτών των αέριων ρυπαντών βελτιώνει σημαντικά τη γνώση μας, προκειμένου να καταλάβουμε αλλά και να διαχειριστούμε σωστά τέτοιου είδους σοβαρά περιβαλλοντικά προβλήματα. Στην παρούσα εργασία επεξεργαζόμαστε στατιστικά τα δεδομένα από 16 σταθμούς καταγραφής ατμοσφαιρικών ρύπων στην περιοχή της Αθήνας. Πιο συγκεκριμένα διαθέτουμε τις συγκεντρώσεις των αιωρούμενων σωματιδίων PM10 , του μονοξειδίου και διοξειδίου του αζώτου , του όζοντος , του μονοξειδίου του άνθρακα και του διοξειδίου του θείου για το έτος 2006, αλλά και τα μετεωρολογικά δεδομένα για το συγκεκριμένο έτος. Αναπαριστούμε γραφικά τις μέσες ημερήσιες αλλά και μηνιαίες τιμές για καθένα από τους παραπάνω ρύπους, για όλους τους σταθμούς στους οποίους μετρώνται οι συγκεντρώσεις τους και εξάγουμε συμπεράσματα για τις ώρες της ημέρας, αλλά και για το ποιούς μήνες, έχω τις μέγιστες τιμές για τον κάθε ρύπο. Ακόμα εξάγουμε συμπεράσματα σχετικά με τη συχνότητα εμφάνισης υπερβάσεων των θεσμοθετημένων ορίων , καθενός εκ των πιο πάνω ρυπαντών. Εφαρμόζουμε την μέθοδο της ανάλυσης γραμμικής παλινδρόμησης, με την οποία διαπιστώνουμε με ποιούς από τους υπόλοιπους ατμοσφαιρικούς ρύπους και με ποιες μετεωρολογικές παραμέτρους συσχετίζονται γραμμικά τα αιωρούμενα σωματίδια ενώ παρατηρούμε κάποια ετερογένεια ανάμεσα στους σταθμούς μέτρησής τους. Τέλος μέσω της διαδικασίας της ετεροσυσχέτισης των χρονοσειρών των ατμοσφαιρικών ρύπων των αιωρούμενων σωματιδίων, του μονοξειδίου του άνθρακα και του διοξειδίου του αζώτου μεταξύ των σταθμών καταγραφής τους, εξάγουμε συμπεράσματα σχετικά με τη συμπεριφορά των αντίστοιχων χρονοσειρών, δηλαδή το μέγεθος της σχέσης ανάμεσα στις δύο σειρές και τη χρονική απόσταση ανάμεσα στη θέση της μέγιστης ισοδυναμίας τους. / The development of big cities resulted in large emissions of suspended particulate matter (PM) and other pollutants in the atmosphere, which link to air quality deterioration. Monitoring and studying air pollutants improves our knowledge in order to understand and manage such significant environmental problems. In the present work, we perform statistics in the data of the 16 monitoring stations in Athens area. More specifically our data consists of the concentrations of PM10, NO, NO2, O3, SO2 and CO, as well as the meteorological data of the year 2006. We graphically represent mean daily and monthly values of each air pollutant and make appropriate conclusions. Moreover we deal with the exceedances of these air pollutants concentrations. We perform linear regression analysis in order to find out, which of the rest pollutants and meteorological data, PM10 have the best linear line fit with. We find enough differences between the monitoring stations. Finally through the cross correlation procedures of the time series of PM10, CO and NO2 between the monitoring stations, we make conclusions regarding the behavior of the time series as concerning the type of the relationship between them and the time distance between their maximum equivalence.
176

Estimating the volatility of aerosol components and diffusion through the particle-phase

O'Meara, Simon January 2017 (has links)
Accurate models of aerosol transformation including partitioning between the gas- and particle-phase are needed for estimating their effects on climate and air quality. In this thesis, the process of partitioning between phases and its determining factors are introduced and investigated. Three studies assess: the accuracy of estimation methods for aerosol component volatility and its effect on particulate concentration and composition; the consistency of different solutions to models of particle-phase diffusion; and, a method to analytically solve particle-phase diffusion. These studies contribute to the ongoing effort of improving aerosol models, such that their wide-ranging effects can be accurately estimated.
177

Emise tuhých znečišťujících látek v chovech drůbeže / Emissions of particulate matter in poultry farms

VACOVSKÝ, Miroslav January 2015 (has links)
Among the considerable factors in poultry include climatic conditions, where the breeding takes place. This work focuses on the content of solid particles PM10 and PM2,5 occurring in this environment. These particles can negatively affect the health status of breeding and staff, ensuring the necessary care in poultry farming. Dust particles settle on the skin, where they have an irritant effect or are inhaled into the respiratory tract bodies of birds. These particles are transferred microorganisms causing a variety of diseases. It is therefore desirable to eliminate the amount of such particles to the maximum extent possible.
178

Analýza emisí tuhých znečišťujících látek v chovu drůbeže / Analysis of emissions of particulate matter in poultry farming

ADAMOVSKÝ, Vojtěch January 2016 (has links)
This thesis was focused on monitoring production of dust particles in poultry farming. This measurement was made with the Dusttrak II 8530 which monitored the environment in the stable every 3 seconds for 24 hours. For monitoring were selected companies in the South Bohemian Region, specifically MTD Ústrašice and Farma u lesa. Results of Dusttrak measurements showed that none of the stables exceeded the permissible limits of dust particles. Additionally microscopic analysis of the samples of dust particles revealed that the main component of source of dust was feed mixture.
179

Caracterização de íons majoritários presentes no material particulado atmosférico do entorno da Baía de Todos os Santos-BA

Silva, José Domingos Santos da January 2011 (has links)
106 f. / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-04-03T14:21:08Z No. of bitstreams: 4 SUMÁRIO.pdf: 251853 bytes, checksum: 136967f071e8c9dc1f1d9dc61b6ba5ed (MD5) RESUMO.pdf: 90333 bytes, checksum: 6feb676556b5519091aca62ba1aef7f9 (MD5) INTRODUÇÃO.pdf: 4006502 bytes, checksum: 77f35936fb80d965a1c446cf7b35deed (MD5) CAPA.pdf: 247759 bytes, checksum: 0319a707474146fc6565e0c7806729e3 (MD5) / Rejected by Ana Hilda Fonseca(anahilda@ufba.br), reason: Solicito o envio em arquivo único. on 2013-04-18T15:44:07Z (GMT) / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-05-20T15:25:26Z No. of bitstreams: 1 Dissertação José Domingos S da Silva.pdf: 4188732 bytes, checksum: 5a2a0590c7239c937525ccc66385274d (MD5) / Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-05-20T15:27:50Z (GMT) No. of bitstreams: 1 Dissertação José Domingos S da Silva.pdf: 4188732 bytes, checksum: 5a2a0590c7239c937525ccc66385274d (MD5) / Made available in DSpace on 2013-05-20T15:27:50Z (GMT). No. of bitstreams: 1 Dissertação José Domingos S da Silva.pdf: 4188732 bytes, checksum: 5a2a0590c7239c937525ccc66385274d (MD5) Previous issue date: 2011 / CAPES / Um grande número de estudos epidemiológicos tem mostrado uma relação entre a exposição ao ambiente de partículas em suspensão e os efeitos adversos na saúde humana além de danos à flora, fauna, edificações dentre outros. Segundo alguns estudos o MPA afeta a saúde da população, causando várias patologias do trato respiratório (alergias, asma, enfisema pulmonar) e mortalidade cardiopulmonar, sendo responsável por grande numero de mortes em todo o mundo. Este trabalho teve por objetivo desenvolver e validar metodologia para determinação de íons presentes nas frações PM1 e PM2,5 no Material Particulado Atmosférico da atmosfera do entorno da Baía de Todos os Santos (BTS). Durante o desenvolvimento do trabalho foram coletadas amostras de MPA com a utilização de dois amostradores tipo ciclone com faixa de corte de PM1 e PM2,5 ligados a uma bomba de vácuo a uma vazão fixa de 10L min-1 por períodos de 12h durante 15 dias em três sítios de amostragem nos seguintes períodos: Botelho, Base Naval de Aratu (BNA) e Itaparica. As amostras coletadas foram coletadas e depois analisadas por cromatografia de íons com dois canais. Os íons determinados nos três sítios foram lactato, acetato, butirato, formiato, succinato, oxalato, amônio, fluoreto, cloreto, nitrato, sulfato, fosfato, sódio, potássio, magnésio e cálcio, a seguinte relação entre ânions e cátions nas frações PM1 e PM2,5. Dentre os três sítios o que apresentou maiores concentrações médias destes íons foi Botelho, isso ocorreu devido a sua posição geográfica em relação aos ventos que sopram nesta região durante a estação de inverno na qual as amostras foram coletadas as concentrações menores foram no sitio da BNA por estar em posição geográfica oposta em relação aos ventos. Para todos os sítios a relação iônica equivalente (ânions/cátions) sempre foi maior que um o que mostra que há mais cátions que ânions e, portanto, trata-se de caráter ácido. No sitio de Botelho foi encontrado um prevalência de íons emitidos por fontes industriais, ressuspensão de partículas, por emissão da flora e fonte secundaria. Em BNA houve prevalência de queima de combustível. Em Itaparica houve prevalência de emissões veiculares e de ressuspensão de partículas. / Salvador
180

Caracterização de íons majoritários em material particulado atmosférico da região de Caetité, Bahia

Sousa, Yara Simone Chaves 05 1900 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2014-10-30T17:42:26Z No. of bitstreams: 1 Yara Simone Chaves Sousa.pdf: 1952490 bytes, checksum: 4793b77a14d9a54dcddaf25b39290f81 (MD5) / Approved for entry into archive by Ana Hilda Fonseca (anahilda@ufba.br) on 2014-10-31T12:39:01Z (GMT) No. of bitstreams: 1 Yara Simone Chaves Sousa.pdf: 1952490 bytes, checksum: 4793b77a14d9a54dcddaf25b39290f81 (MD5) / Made available in DSpace on 2014-10-31T12:39:02Z (GMT). No. of bitstreams: 1 Yara Simone Chaves Sousa.pdf: 1952490 bytes, checksum: 4793b77a14d9a54dcddaf25b39290f81 (MD5) / CNPq / Este trabalho teve como objetivo determinar íons majoritários no material particulado proveniente da região de Caetité. A coleta das amostras foi realizada através de amostradores do tipo ciclone com corte MP1 e MP2,5, Hi-Vol MP2,5 e Hi- Vol com impactador em cascata, utilizando vazão de 10 L min-1 para os amostradores ciclone e 1,13 m3 min-1 para os amostradores Hi-Vol MP2,5 e Hi-Vol com impactador em cascata e período de amostragem de 24 horas nos dias 12 a 26 de novembro de 2010. As espécies quantificadas foram os íons fluoreto, lactato, acetato, propionato, formiato, butirato, piruvato, cloreto, nitrato, succinato, sulfato, oxalato, fosfato, citrato, lítio, sódio, amônio, potássio, magnésio e cálcio. A quantificação dessas espécies foi realizada através de um cromatógrafo de íons de duplo canal. De acordo com os níveis encontrados no material particulado de ciclone MP1 e MP2,5, as espécies predominaram na fração de tamanho menor que 1 µm, com exceções apenas para NO3-, SO42-, Na+ e Ca2+ que estiveram distribuídos nas duas faixas de tamanho. Os níveis encontrados nas partículas fracionadas por tamanho foram maiores para as espécies com diâmetro aerodinâmico menor que 0,49 µm. Foram observadas trajetórias de massas de ar do tipo oceânica e continental, sendo a primeira a de maior contribuição no período de amostragem. No entanto, não foi comprovada contribuição marinha significativa para as SO42-, K+, Mg2+ e Ca2+. A relação iônica equivalente (ânions/cátions) para as amostras nos diferentes amostradores foi menor que um, evidenciando caráter básico do MP da região de Caetité. Com base nas correlações de Pearson e PCAs, foram identificadas como prováveis fontes emissões biogênicas, como metabolismo de plantas, fungos e bactérias, fontes antrópicas, como emissão por veículos movidos a diesel (usados no transporte da torta amarela de urânio) e emissão de partículas provenientes da extração de minério de urânio e ainda partículas provenientes da ressuspensão do solo. As espécies estudadas apresentaram fluxo de deposição elevado, principalmente para ânions inorgânicos e íons alcalinos, indicando que a deposição seca foi um mecanismo de remoção importante no período de coleta. / This work aimed to determine majority ions in the particulate matter from the region of Caetité-BA. The sample collection was executed through PM1 e PM2.5 cyclone samplers, Hi-Vol PM2.5 and Hi-Vol cascade impactor, using flow rate of 10 L min-1 for cyclone samplers and 1.13 m3 min-1 for the Hi-Vol samplers, during 24 hours 12th 26th November 2010. The quantified species were fluoride, lactate, acetate, propionate, formate, butyrate, pyruvate, chloride, succinato, sulfate, oxalate, phosphate, citrate, lithium, sodium, ammonium, potassium, magnesium and calcium by an ion chromatograph coupled to conductivity detector. According to the levels found in the particulate matter of cyclone PM1 and PM2.5, species predominated in the fraction with size less than 1 µm, with exceptions only for NO3-, SO42-, Na+ and Ca2+ that were distributed in the two size fractions. The levels found in the particles were fractionated by size larger for species with aerodynamic diameter less than 0.49 µm. The equivalent ion balance (anions/cations) for the samples in the different samplers was less than one, evidencing the basic character for particulate matter from Caetité region. Based on Pearson correlation and PCAs were identified as probable sources to be biogenic emissions, such as metabolism of plants, fungi and bacteria, as well as, anthropogenic sources such as emissions from diesel-powered vehicles (used to transport of the yellow cake of uranium and yet particles descendant from the resuspension of soil. The species studied showed high flow deposition, mainly for inorganic anions and alkali ions, indicating that dry deposition was a major removal mechanism in the collection period.

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