The main aim of this work was to compare the genotoxicity of organic extracts from different size fractions of aerosol particles (1-10 µm, 0,5-1 µm, 0,17-0,5 µm) collected by high volume cascade impactors in various localities of the Czech Republic differing in the extent of the environmental pollution (Březno - strip mine, Dobré Štěstí - highway, Praha - city center, Láz - background station). Genotoxicity was determined in acellular assay of calf thymus DNA (CT-DNA) with and without S9 metabolic activation by analysis of DNA adducts induced by extractable organic matter (EOM) from the particulate matter (PM) by 32 P-postlabeling and the ability of extracts to induce oxidative DNA damage was evaluated using the competitive ELISA test. The main finding of this work is that most of the observed genotoxicity is connected with fine particles (<1 µm). The concentration of carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) in EOMs indicate that fine fractions bound the highest amount of c-PAHs in all sampling sites. This fact might be related to a higher specific surface of this fraction as compared with a course fraction and a higher mass as compared with a condensational fraction. As for aerosol mass, both fine and condensational fractions are effective carriers of c-PAHs. Similarly, the DNA...

Health is closely related to air pollution, with increasing evidence showing the consequences of longand short-term exposure to, in particular, fine particulate matter (PM2.5). In 2008, the European Union adopted a directive (directive 2008/50/EC) to improve air quality and to regulate a number of air pollutants, including PM2.5, in the member states. This directive has recently been assessed by a socalled “fitness check”. The aim of this thesis is to analyse how air quality regarding fine particulate matter has developed in Sweden between 2000 and 2018 and to examine possible future scenarios for stricter requirements in renewed EU legislation, based on the outcomes of the “fitness check”. Data are analysed from monitoring stations throughout Sweden with a focus on the last ten years up to 2018. Average urban exposure levels are estimated to compare them with the average exposure index (AEI) defined in the directive and source sectorsfor PM2.5 are identified to determine the potential for measures to reduce concentrations. The results show that Sweden is not challenged by the current EU legislation, neither exceeding the current annual limit value of 25 µg/m3 nor requiring a reduction of the urban exposure levels. However, Sweden will need to take further initiatives if requirements are tightened up, for example if a daily ceiling of 25 µg/m3 is implemented or the annual limit decreased to 10 µg/m3 , both values based on WHO’s latest recommendations. Rural and urban concentrations show an exponentially decreasing trend from southern to northern Sweden. It is concluded that PM2.5 is dominated by long-distance transportation, but with significant local contributions in urban areas. Overall, concentrations reduced during the period studied, which is mainly due to a reduction in international emissions, occasionally combined with individual local measures. PM2.5 concentrations are, however, above natural background levels, which makes it worthwhile to decrease them further, with local action considered to be of particular importance from a health perspective. / Luftkvalitet är en viktig faktor inom hälsa, eftersom ett stort antal negativa effekter på kroppen har fastställts vid exponering av ökade halter partiklar (PM, eng. ”particulate matter”), bland annat, i luft. Både kort- och långtidsexponering av fina partiklar (PM2.5) har dokumenterade hälsofarliga konsekvenser, därför fastställde den Europeiska unionen under 2008 ett direktiv (direktiv 2008/50/EC) för att förbättra luftkvaliteten och reglera ett antal luftföroreningar, bland annat PM2.5-koncentrationerna i medlemsländerna. För att undersöka implementeringen av direktivet utfördes nyligen en så kallad ”fitness check”. Detta arbete ska analysera hur luftkvalitet i samband med fina partiklar har utvecklats i Sverige under perioden 2000 till 2018. Utöver det undersöks möjliga framtidsscenarier för skärpta krav i ett reviderat EU-direktiv vilka är baserade på slutsatserna från denna ”fitness check”. Data från mätstationer i hela Sverige används med fokus på de sista tio åren fram tills 2018. Genomsnittliga urbana exponeringshalter är uppskattade för att jämföra dessa med exponeringsindexet (AEI, eng. ”average exposure index”) som är definierat i direktivet. Källområden för PM2.5 är identifierade för att uppskatta behovet av potentiella åtgärder för att reducera koncentrationen av fina partiklar. Resultaten visar att Sverige når målsättningen i den befintliga EU-lagstiftningen eftersom varken årsmedelvärdet av 25 µg/m3 eller taket för exponeringsindexet överskrids vid mätstationerna. Om kraven skulle skärpas, till exempel vid implementeringen av ett dygnsgränsvärde av 25 µg/m3 eller om det årliga gränsvärdet skulle sänkas till 10 µg/m3 (i enlighet med WHO:s senaste rekommendationer), kommer det krävas ytterligare åtgärder. Den regionala och urbana koncentrationen uppvisar en exponentiellt avtagande trend från södra till norra Sverige. Slutsatsen kan dras att PM2.5 är dominerad av långdistanstransporter, dock med synliga lokala tillskott i de urbana områdena. Sammanfattningsvis har koncentrationerna reducerats under den observerade perioden, vilket framförallt kan antas vara baserat på en reducering av internationella emissioner, i vissa fall kombinerat med lokala åtgärder. PM2.5 koncentrationerna är fortfarande högre än den naturliga förekomsten, därför är det relevant ur ett hälsoperspektiv att även reducera dem i framtiden, framförallt på lokal nivå.

This dissertation is a collection of studies that investigates the issue of air pollution in the field of environmental chemistry. My thesis consists of research works done to measure the concentration of particulate matter (PM) and gas-phase species in ambient air. High concentrations of PM is a significant problem in Utah and in other regions of the world. Particles having an aerodynamic diameter of 2.5 micrometers and smaller play a crucial role in air pollution and pose serious health risks when inhaled. PM is composed of both organic and inorganic components. The organic fraction in PM ranges from 10-90% of the total particle mass. Several methods have been employed to measure the organic fraction of PM, but these techniques require extensive laboratory analysis, expensive bench top equipment, and do a poor job of capturing diurnal variations of the concentrations of ambient organic compounds. The Hansen Lab has developed a new instrument called the Organic Aerosol Monitor (OAM) which is based on gas chromatography followed by mass spectrometry detection platform for measuring the carbonaceous component of PM2.5 on an hourly averaged basis. Organic marker data collected in 2016 using the OAM was used in a Positive Matrix Factorization (PMF) analysis to identify the sources of PM in West Valley City, Utah. Additionally, data was collected in Richfield and Vernal, UT in 2017 - 2018 to quantitatively monitor the composition of organic markers of PM2.5. Some previously unidentified organic compounds in PM were successfully identified during this study, including terpenes, polycyclic aromatic hydrocarbons (PAHs), diethyl phthalate, some herbicides, and pesticides. Gas-phase species play a significant role in driving the formation of air pollutants in Earth's atmosphere. Traditional gas detection methods do not provide high temporally and spatially resolved data; therefore, it becomes important to detect and measure gas-phase species both qualitatively and quantitatively to better understand the sources of air pollution. An incoherent broadband cavity enhanced absorption spectrometer (IBBCEAS) combines a broadband incoherent light source, a stable optical cavity formed by two highly reflective mirrors and a charged-coupled device (CCD) detector to quantitatively measure the gas-phase compounds present in the atmosphere. The concentrations of formaldehyde (HCHO) were measured using IBBCEAS to investigate the sources of this hydrocarbon in Bountiful, Utah during 2019. Another important species is OH radical. It is one of the most predominant oxidizing species present in the atmosphere. It is found in low concentrations, 0.1 ppt. Detecting concentrations this low is challenging. A new IBBCEAS instrument has been designed and elements of this instrument were tested by measuring the OH overtones in a variety of short chained alcohols. A set of experiments were conducted to measure the absorption cross-sections for the 5th and 6th OH vibrational overtones in a series of short chained alcohols by IBBCEAS. Because OH radical's lowest energy electronic state occurs in the same wavelength region (i.e., 308 nm) that SO2 absorbs (300-310 nm), a study was conducted in which the concentrations of SO2 were measured using an IBBCEAS and compared with a commercially available SO2 monitor.

La combustion de la biomasse est l’une des sources majoritaires de particules atmosphériques en périodes hivernales dans les vallées alpines, et particulièrement en vallée de l’Arve où des dépassements des seuils européens sont très régulièrement observés. Ceci a conduit à la mise en place d’un large programme de remplacement des dispositifs de chauffage au bois les moins performants dans le cadre d’une des actions du Plan de Protection de l’Atmosphère, le Fond Air Bois. Le projet DECOMBIO (DÉconvolution de la contribution de la COMbustion de la BIOmasse aux PM10 dans la vallée de l’Arve) a ainsi été mis en place en octobre 2013 afin de mesurer l’impact de cette politique de rénovation des appareils de chauffage au bois sur la qualité de l’air. C’est dans ce programme que s’inscrivent ces travaux de thèse dont l’objectif principal est de valider les méthodologies mises en place en routine pour permettre une déconvolution rapide de la combustion de la biomasse et mettre en relation les éventuels changements observés avec les avancées des remplacements de dispositifs de chauffage au bois domestiques.Pour mener à bien ce travail, trois sites, représentant les différentes situations de la vallée de l’Arve, ont été instrumentés (Marnaz, Passy et Chamonix) afin de suivre en continu, et tout au long du projet DECOMBIO, l’évolution des concentrations atmosphériques du Black Carbon (BC) et des traceurs moléculaires permettant de distinguer la contribution de la combustion de la biomasse des autres types de combustion. Un important jeu de données a été acquis entre novembre 2013 et octobre 2014 grâce à des prélèvements réguliers sur filtre permettant une caractérisation très fine de la composition chimique des particules atmosphériques. L’utilisation de l’approche statistique « Positive Matrix Factorization » (PMF) a permis de mieux appréhender les différentes sources entrant en jeu dans les émissions de particules au sein de cette vallée avec notamment un intérêt particulier pour les émissions de la combustion de la biomasse. Le développement de cette méthodologie d’attribution et de quantification des sources de particules basé sur l’utilisation de traceurs organiques spécifiques, de contraintes particulières appliquées à ce modèle et de données de déconvolution de la matière carbonée constitue une avancée importante dans la définition des facteurs sources issus de ce modèle.Les méthodologies développées au cours de ce travail, permettant une amélioration des connaissances et des contributions des sources, constituent donc des outils directement utilisables par les Associations Agréées de Surveillance de la Qualité de l’Air (AASQA), notamment pour l’évaluation quantitative des mesures prises pour améliorer la qualité de l’air dans le cadre de Plans de Protection de l’Atmosphère, entre autres celui de la vallée de l’Arve. / Biomass burning is one of the major sources of atmospheric particles during wintertime in Alpine valleys, and more especially in the Arve valley where exceedances of the European regulated limit value are regularly observed. This situation led to the establishment of an important program of replacement of old wood stoves with new ones as part of an action of an Atmospheric Protection Plan (APP), the “Fonds Air Bois”. The research program DECOMBIO (“DÉconvolution de la contribution de la COMbustion de la BIOmasse aux PM10 dans la vallée de l’Arve”) has been set up in October 2013 to estimate the impact of this wood stoves renewal policy on air quality. This thesis works be incorporated within this program and have for main objective to validate methodologies used in routine to enable a fast deconvolution of the biomass burning source and to compare any observed changes with progress of wood stove changeout.To complete this work, three sites, representing the different situations of the Arve valley, were instrumented (Marnaz, Passy and Chamonix) to monitor the continuing evolution of atmospheric concentrations of Black Carbon (BC) and molecular markers enabling to distinguish between the biomass burning contribution and that of other types of combustion. A large dataset was acquired between November 2013 and October 2014 thanks to regular filter samples enabling a vast chemical characterization of PM10. The use of statistical analysis “Positive Matrix Factorization” (PMF) has led to an enhanced appreciation of particle emission sources within this valley with a focus on biomass burning emissions. The development of this methodology of identification and source apportionment based on the use of specific organic markers, specific constraints and data from carbonaceous matter deconvolution is an important progress in definition of factors from this model.The developed methodologies during this work, enabling an improvement of knowledges and source apportionment, are tools directly usable by French Accredited Associations for Air Quality Monitoring, especially for the quantitative assessment of actions introduced to improve air quality as part of Atmospheric Protection Plans, for example the one in the Arve valley.

La pollution atmosphérique particulaire constitue un facteur de risque majeur pour la santé humaine. En dépit des nombreuses études réalisées, les mécanismes d'action sous-jacents à l'exposition aux particules et responsables des effets physiopathologiques observés restent encore mal connus. Notre travail a consisté en la collecte d'aérosols particulaires sur 2 sites urbains (Fann et Faidherbe) dans la ville de Dakar (Sénégal) et un site rural (Ngaparou). Les sites urbains sont caractérisés par un trafic automobile dense avec le site de Fann présentant une circulation majoritaire de véhicules de transport en commun alors qu'à Faidherbe le trafic est constitué en majorité de véhicules particuliers. la caractérisation physico-chimique des trois échantillons particulaires a montré une granulométrie fine (96% < 2,5 μm), donc capables de pénétrer profondément dans les poumons, des surfaces spécifiques comprises entre 8 et 13m²/g pouvant adsorber à leur surfaces des substances potentiellement toxiques. Leur composition chimique, riche en éléments inorganiques et organiques, démontre la diversité de leur sources (naturelle et anthropique). Après évaluation de leur cytotoxicité dans les cellules épithéliales bronchiques humaines (BEAS-2B), nous avons montré la capacité de ces aérosols particulaires à induire l'activation métabolique de leur fraction organique par l'induction de l'expression génique des enzymes de métabolisation CYP1A1, 1B1 et NQO1. Nous n'avons pas observé de réponse significative dans le processus d'altération oxydative via la péroxydation lipidique (MDA) et le statut du glutathion (GSSG/GSH). En revanche nous avons montré l'implication de ces aérosols particulaires dans le développement de la réponse inflammatoire par l'expression et la sécrétion significative de cytokines TNF-α, IL-1β, IL-6 et IL-8. / Airborne Particulate Matter (PM) is an important risk factor for human health. In spite of the numerous studies that have been carried out, the underlying mechanisms of action involved in particulate matter physiopathological effects are still unclear. In this work, PM samples were collected in two urban sites (Fann and Faidherbe) in Dakar (Senegal) and in a rural site (Ngaparou). The two urban sites mainly differ in the type of motor vehicles circulating in the area : most of the traffic is made of buses in Fann, whereas they are absent from Faidherbe. The physical characterization of the three samples showed their fine size distribution (96% < 2,5 μm), with surface areas ranging from 8 to 13m²/g. Collected PM were then able to reach deep lung, and to adsorb potentially toxic substances. Their chemical composition, rich in inorganic and organic compounds demonstrated the diversity of emission sources. After assessing their cytotoxicity in human epithelial bronchial cells (BEAS-2B), we showed that these PM could induce gene expression of metabolizing enzymes CYP1A1, 1B1 and NQO1, and therefore the metabolic activation of their organic fraction. No significant response to oxidative damage through lipid peroxidation (MDA) or glutathione status modification (GSSG/GSH) was observed after cells exposure to particulate matter. However, this exposure induced an inflammatory response by a significant increase in expression and secretion of cytokines TNF-α, IL-1β, IL-6 and IL-8.

La contamination en composés aromatiques polycycliques (CAP) a été suivie entre 2014 et 2015 au cours de six campagnes d’échantillonnage sur 8 sites différents entre Auboué et Richemont. Cette section du cours d’eau correspond à la partie aval de la vallée de l’Orne profondément affectée par plus d’un siècle d’activités minières et sidérurgiques qui ont cessé entre 1968 et 2009. L’Orne a donc été le réceptacle de rejets industriels et urbains et a été profondément perturbée dans son hydrodynamisme avec la construction de plusieurs barrages. Dans ce contexte, l’occurrence des 16 hydrocarbures aromatiques polycycliques réglementaires (HAP), de 11 CAP oxygénés (O-CAP) et de 5 CAP azotés (N-CAP) et leur distribution dans les fractions dissoute et particulaire des eaux de l’Orne ont été étudiées en mettant en place des protocoles d’échantillonnage et d’analyse adaptés. Le premier objectif de ce travail a été de comparer les méthodes d’échantillonnage des matières en suspension par filtration et par centrifugation à flux continu sur le terrain. Des différences significatives ont pu être identifiées entre les deux techniques, la filtration amenant à des concentrations en CAP plus élevées du fait d’une plus grande abondance des CAP de bas poids moléculaire. Nous avons pu mettre en évidence le rôle de la fraction fine (< 5µm) et/ou colloïdale plus ou moins retenue par les filtres et qui, de part sa réactivité, piège des CAP. La comparaison des deux méthodes dans différentes situations hydrologiques nous montre que cette rétention n’est pas systématique mais plutôt corrélée à des situations de fort hydrodynamisme. Les deux méthodes d’échantillonnage des matières en suspension ne sont donc pas comparables mais complémentaires. Le suivi saisonnier et multi-sites des eaux de l’Orne montre que la concentration en CAP varie entre 1.6 et 223.7 ng L-1 dans la fraction dissoute et entre 1.5 et 105.5 µg g-1 dans la fraction particulaire avec des variations spatiales de ±35% et ±45% respectivement. Les variations de concentration des CAP dans la fraction dissoute sont importantes d’un site à l’autre lorsque le débit est faible (de 0.5 à 34 m3.s-1). Les concentrations en CAP sont faibles autour de 20 ng.L-1 et spatialement homogènes en périodes de haut débit (> 50 m3.s-1) du fait de la dilution. Les concentrations en CAP dans les matières en suspension varient entre 2.8 to 36.3 µg g-1, et montrent des concentrations stables quelles que soient les situations hydrologiques lorsqu’elles sont collectées par la centrifugeuse de terrain. La fraction dissoute est enrichie en HAP de bas poids moléculaire dans les périodes d’étiage et est marquée par l’occurrence des HAP à 5 et 6 cycles aromatiques au cours des épisodes de crue. Les CAP polaires sont au moins aussi abondants que les HAP dans la fraction dissoute et évoluent de la même façon que les HAP. La part des CAP polaires dans la fraction particulaire est significativement plus basse (de 10 à 20% de l’ensemble des CAP) / The spatio-temporal variations of the concentration and distribution of dissolved and particulate polycyclic aromatic compounds (PACs), namely 16 polycyclic aromatic hydrocarbons (PAHs), 11 oxygenated PACs (O-PACs) and 5 nitrogen PACs (N-PACs), were studied in the Orne, a river impacted for more than one century by iron mining and steel-making industry. The first objective of this work was to compare the influence of two different methods of separation of suspended particulate matter (SPM), filtration (FT) and field continuous flow centrifuge (CFC). Results showed that in half of the sampling campaigns, PAC concentrations were 2 to 8 times higher for PAHs and 2 to 10 times higher for O-PAC when SPM were collected by filtration. These differences that were not observed systematically over the six sampling campaigns could be explained by the retention of colloidal matter on glass-fiber filters that appeared as a very reactive phase particularly enriched in low molecular PACs. The two methods were then considered as complementary methods to study SPM. The second objective of this work was to perform a long term monitoring of PAC concentrations and distributions in dissolved and particulate fractions. The results from the six sampling campaigns between May 2014 and September 2015 in eight different sites showed that the PAC concentrations ranged between 1.6 to 223.7 ng L-1 in the dissolved fraction (?PACTD), and between 1,55 to 105,5 µg g-1 in the total particulate fraction, with maximum spatial variation of ±35% and ±45% respectively. The dissolved PACs spatial variations were strongly influenced by the hydrological conditions and less spatial variation was observed during high flow events as the result of dilution and homogenization of pollutants. During low flow events, particulate PACSPM-CFC concentrations were more stable and equivalent in values and distribution to the corresponding PACSPM-FT samples. Overall it was in a range between 2.8 to 36.3 µg g-1. The dominance of dissolved low molecular weight PAHTD in the low flow events decreased during high flow events due to the appearance of penta- and hexa-cyclic PAHs. The dissolved polar PACs were as high as the PAHs contribution and also subjected to seasonal changes, the O-PACs ranged between 5.6 to 90.3 ng L-1 and N-PAHs from 1.0 to 42.5 ng L-1. The particulate polar PACs concentrations and contribution were significantly lower, the highest concentrations of 8,76 µg g-1 and 29,41 µg g-1 was observed during high flow event for O-PACs and during low flow event for N-PAH respectively

<p>Particle pollution in South Korea has become a matter of significant public concern, culminating in its declaration as a “social disaster” through a government proclamation in 2019. This study shows how the existing interventions to tackle particle pollution in South Korea as a “social disaster” contribute to maintaining the status quo, paradoxically. The study attempts to interpret pollution as entanglements, relations, and processes by addressing the discussions and politics surrounding particle pollution, the interventions to tackle it, and what they presuppose and exclude via multi-sited ethnography.</p> <p>What narratives form the bedrock of the current discourses and politics around particle pollution in South Korea? What kinds of population, knowledge systems, values, and interests are incorporated and excluded around particulate matter in Korea? Drawing upon four months of fieldwork, interviews, and collaborative work with residents, scientists, and activists in South Korea, this thesis offers a new understanding of how citizens’ experiences and knowledge practices have reshaped the concepts of pollution, toxicity, and health. The study indicates that the existing practices and knowledge vis-à-vis pollution control have individualized pollution by presuming particular ways of normalcy and excluding others. In doing so, this study captures the multiplicity of particle pollution and shows the existence and stories of different bodies living with/in pollution.</p> <p>Drawing on the literature in feminist science and technology studies as well as medical and environmental anthropology scholarship, this study problematizes harm reduction-based environmental and health intervention practices by describing the current individualized particle pollution responses. The research reveals how people in Korea living with/in particulate matter have perceived, datafied, defined, adjusted, and responded to particle pollution and its toxicity. The study suggests that pollution should be envisaged as entanglements and relations by shedding light on the stories that particulate matter has been perceived, coordinated, and generated in various ways. Lastly, indicating that the knowledge and interventions surrounding particle pollution have exploited and flattened the environment based on the human–nature dichotomy, the study suggests different ways of conceptualizing pollution, while considering the multiplicity of pollution, toxicities, and bodies.</p>

This research investigates particulate matter (PM) deposition to rock pigeons (Columba livia) in urban environments within Denton County, Texas. Pigeon habitat was characterized within a 2-km radius at eight locations using the 2016 National Land Cover Database (NLCD). In summer 2020, feathers were sampled from 10 rock pigeons at two locations (n = 20) differing in degree of urban development. Birds were captured using walk-in funnel traps baited with bird seed. Based on molt pattern and appearance, four old flight feathers were identified and sampled from each bird. New primary feathers were obtained from each population as reference samples. Feathers were washed three times with double deionized water and acetone, and the solution vacuum filtered through a glass microfiber filter to collect all particles >1.5 µm in diameter. Particulate matter mass was determined by gravimetric analysis and calculated per unit feather surface area. Relative PM accumulation rates were significantly different between the populations. Characteristics of urban land cover, proximity to and types of emissions sources, wind exposure, and building density were drivers of variability in PM deposition to feather surfaces. The results from this study should be useful for subsequent research to help identify best practices for using feathers collected from pigeons or other urban restricted bird species to monitor PM levels across multiple spatial scales.

Erosion et transferts de matières (i.e. matières en suspension-MES, associées avec le carbone et les éléments traces métalliques - ETM) par les fleuves et rivières sont contrôlés par des facteurs naturels (ex. géologie, climat) et peuvent être significativement modifiés par les pressions anthropiques et/ou, le changement climatique. En se basant sur une banque de données de concentrations en MES et de débits, à hautes résolutions temporelles (journalières) sur le long terme (1960-2008) à l’exutoire du bassin versant du Fleuve Rouge (Chine/Vietnam), les taux d’érosion ont été estimés en moyenne à 600 t/km²/an avec des valeurs variant de 160 à 1330 t/km²/an selon les années. Cette large gamme de taux d’érosion est liée fortement aux conditions hydrologiques interannualles, mais aussi à la présence de réservoir de HoaBinh en 1989. En effet, à partir 1989, chaque année, 50% de matières transportées par le Fleuve Rouge sont piégées dans ce réservoir, correspondant à un taux de sédimentation dans le réservoir de 52 à 200 cm/an. La variabilité spatiale des flux de MES du bassin versant du Fleuve Rouge au Vietnam suggère que les MES du Fleuve Rouge viennent principalement de l’érosion en amont du bassin versant (~80%), contrairement à ce que l’on observe pour le flux liquide (~21%). De plus, l’échange des processus érosion-transport-sédimentation dans la partie médiane du bassin versant dépend fortement des conditions hydrologiques ; à l’inverse, une forte sédimentation a été observée à l’entrée du Fleuve Rouge dans le delta, quelle que soit la condition hydrologique. De même, dans la partie vietnamienne du Fleuve Rouge, les facteurs majeurs influant sur le taux d’érosion seraient les maximas d’élévation et la pente moyenne du bassin. Un suivi hebdomadaire à bimestriel en 2008-2009 des paramètres biogéochimiques (carbone et ETM) ont permis de caractériser la qualité des eaux et des particules sur l’ensemble du bassin versant du Fleuve Rouge. Les concentrations en carbone organique (particulaire et dissous) dans les eaux du Fleuve Rouge sont relativement faibles et majoritairement d’origine allochtone. Les concentrations en carbone inorganique dissous (CID) sont très importantes, en faisant le composé majoritaire (60-90%) des eaux du Fleuve Rouge, en relation avec la présence de roches carbonatées dans le bassin versant. En terme de concentrations en ETM, la qualité des eaux et des particules transportées dans le bassin versant du Fleuve Rouge au Vietnam peut être qualifiée de mauvaise dans la partie amont et de médiocre en aval. L’étude de la répartition entre phase dissoute et phase particulaire a montré que l’essentiel des transferts se fait sous forme particulaire pour plupart des ETM (excepté Mo), dû aux forts taux d’érosion mécanique. De plus, l’étude à haute résolution spatiale (40 points) réalisée sur l’ensemble bassin versant du Fleuve Rouge au Vietnam des concentrations en ETM et de leur spéciation (dissous et particulaire) a mis en évidence de fortes anomalies géochimiques dans la partie amont. Enfin, l’identification des signatures géochimiques des particules érodées a révélé des signatures similaires entre les particules de l’amont et de l’aval du Fleuve Rouge, démontrant une contribution quasi-exclusive de la partie chinoise aux flux de matière (80-95% au flux total). / Erosion and transfer of suspended particulate matter (SPM), and associated elements (e.g. carbon, trace metal elements-ETM) by river are attributed to a combination of natural parameters related to geology and climatic influences and affected by human disturbance. Based on an extensive dataset of daily water discharge and SPM concentrations between 1960 and 2008 at the outlet of the Red River system, the annual SPM yield of the Red River is estimated at 600 t/km²/yr (ranged between 160 and 1330 t/km²/yr). This large range of sediment yield is strongly related to the inter-annual hydrological conditions and the operation of the HoaBinh Reservoir in 1989. In fact, the HoaBinh Reservoir reduces annual SPM delivery to the delta by half after 1989, i.e. the mean sedimentation rate of 52-200 cm/yr. The spatial variability of SPM fluxes in the Red River watershed suggests that most SPM were eroded from the upstream catchment located in China (80%), contrasting the water discharge with only 21%. In addition, the complex processes of erosion/sedimentation occurring in the middle Red River basin strongly depend on hydrological conditions; in contrast, an important sedimentation was observed at the entry point to the Red River Delta whatever the hydrological conditions. The major factors controlling the spatial variation of the sediment yields of the Vietnamese Red River watershed are maximum elevation and mean surface.During 2008-2009, high resolution sampling (weekly to bimestrial) of biogeochemical parameters (carbon and ETM) were performed at five key sites along the Red River system. The organic carbon (particulate and dissolved) concentrations in the Red River are relatively low and mainly allochtonous; in contrast, the dissolved inorganic carbon are very important and is the major carbon form (60 -90%) in relation to the abundance of carbonate rocks in the Red River watershed. In terms of ETM concentrations, the quality of water and SPM transported in the Vietnamese Red River watershed can be classified as poor upstream and as mediocre downstream. The study of the partition between the dissolved and particulate phases showed that most ETM transported in the Red River are in particulate phase (except Mo), due to the high mechanical erosion rate. In addition, high spatial resolution study (40 sites) performed in the Vietnamese Red River watershed of ETM concentrations and their speciation (dissolved and particulate) has highlighted strong geochemical anomalies in the upstream Red River. Finally, the identification of geochemical signals showed a similarity in the geochemical signal of particulate metal transport between upstream and downstream of the Red River, suggesting a contribution quasi-exclusively from the upstream part (in China) in the ETM fluxes of the Red River (80 -95%). / Quá trình xói mòn và vận chuyển vật chất (chất rắn lơ lửng, các-bon và kim loại nặng) bởi các dòng sông, suối chịu ảnh hưởng tổng hợp từ các quá trình tự nhiên (địa chất, khí hậu) và các hoạt động của con người. Dựa trên các bảng số liệu ngày về hàm lượng chất rắn lơ lửng và lưu lượng nước trong giai đoạn từ năm 1960 đến năm 2008 trên trục chính của sông Hồng tại trạm Sơn Tây (hạ nguồn của hệ thông sông Hồng trước khi chảy vào vùng đồng bằng), mục tiêu đầu tiên của luận án là nghiên cứu sự biến đổi theo thời gian tải lượng trung bình chất rắn lơ lửng của sông Hồng. Các kết quả cho thấy trong giai đoạn quan trắc, hàng năm sông Hồng chuyển tải ra biển khoảng 24×106 đến 200×106 tấn/năm (trung bình các năm là 90×106 tấn /năm), tương đương với hệ số xâm thực từ 160 đến 1330 tấn/km²/năm. Chính sự phụ thuộc mạnh mẽ của hàm lượng chất rắn lơ lửng vào các điều kiện thuỷ văn khác nhau đã tạo ra sự đa dạng về tải lượng chất rắn chuyển tải hàng năm của hệ thống sông Hồng. Tuy nhiên, trong những năm 1989-1990, khi hồ chứa Hoà Bình đi vào hoạt động, tải lượng chất rắn lơ lửng chuyển tải ra biển của hệ thống sông Hồng đã giảm sút còn khoảng 50×106 tấn, tức là đã giảm khoảng 50%. Dựa trên chiều cao và thể tích của hồ Hoà Bình, hệ số lắng đọng chất rắn lơ lửng trong lòng hồ được xác định vào khoảng 52-200 cm/năm. Như vậy, sau 20 năm đi vào hoạt động, độ dầy lớp bùn đất lắng đọng trong hồ Hoà Bình khoảng 10.4-40m, làm giảm đáng kể thể tích của hồ Hoà Bình.Mục tiêu tiếp theo của luận án là thiết lập cân bằng hàm lượng chất rắn lơ lửng trong các đoạn sông từ thượng nguồn sông Hồng (trạm Lào Cai), tại các hạ nguồn của 3 nhánh sông chính (sông Hồng tại Phú Thọ, sông Đà và sông Lô tại Việt Trì) và tại Sơn Tây trong thời kỳ 2003-2008. Diễn biến của các quá trình xói mòn, chuyển tải và lắng đọng diễn ra trên các đoạn sông một cách phức tạp, đan xen lẫn nhau và phụ thuộc chặt chẽ vào các điều kiện thuỷ văn. Tuy vậy, hiện tượng lắng đọng mạnh mẽ các chất rắn lơ lửng trong vùng hạ nguồn của hệ thống sông Hồng (từ Phú Thọ đến Sơn Tây) đã được ghi nhận trong tất cả các năm quan trắc, không phụ thuộc vào điều kiện thuỷ văn. Ngoài ra, dựa vào các số liệu thu thập được, chúng tôi đã lập bản đồ xói mòn cho toàn bộ lưu vực sông Hồng tại Việt Nam. Hơn thế, các kết quả còn chỉ ra rằng độ cao và độ dốc trung bình lưu vực là hai yếu tố chính ảnh hưởng đến hệ số xâm thực của lưu vực sông Hồng.Đánh giá chất lượng nước và chất lượng chất rắn lơ lửng chuyển tải trong hệ thống sông Hồng là mục tiêu thứ 3 của luận án. Để đạt được mục tiêu trên, chúng tôi đã tiến hành lấy các mẫu nước và chất rắn lơ lủng trên trục chính cũng như trên các nhánh sông chính của sông Hồng để phân tích hàm lượng các-bon hữu cơ và vô cơ cũng như hàm lượng kim loại nặng trong hai năm 2008-2009, với chu kì lấy mẫu hàng tuần đến hàng tháng. Hàm lượng các-bon hữu cơ (dạng hoà tan và lơ lửng) trong nước sông Hồng tương đối thấp tại tất cả các điểm lấy mẫu và nguồn gốc chính của các-bon hữu cơ là allochtone. Ngược lại, hàm lượng các-bon vô cơ hoà tan rất cao, chiếm khoảng 60-90% hàm lượng các-bon tổng và được giải thích bằng sự có mặt phong phú của núi đá vôi trên toàn lưu vực. Đối với kim loại nặng, dựa trên các kết quả phân tích về hàm lượng kim loại nặng trong nước và trong chất rắn lơ lửng và các tiêu chuẩn đánh giá chất lượng nước QCVN 08, chúng tôi đã đánh giá chất lượng nước cho toàn bộ hệ thống sông Hồng từ Lào Cai đến Sơn Tây. Nếu nước sông Hồng trên vùng thượng nguồn (tại Lào Cai và Phú Thọ) không đảm bảo chất lượng để có thể sử dụng làm nguồn nước sinh hoạt thì tại các vùng hạ lưu của sông Hồng, sông Đà và sông Lô, nhìn chung nước của 3 nhánh sông có thể dùng để cung cấp nước sinh hoạt nhưng phải qua các quá trình xử lí tách cặn lơ lửng. Hơn nữa, trong năm 2008, chúng tôi đã thực hiện hai chương trình lấy mẫu nước, chất rắn lơ lửng và trầm tích trên 40 điểm phân bố đều trên toàn bộ lưu vực sông Hồng tại Việt Nam trong mùa cạn và mùa mưa.

Estudos experimentais feitos em nosso laboratório comprovaram que a inalação de material particulado proveniente da queima de combustíveis fósseis utilizados em siderurgia pelos ratos adultos diminuiu a atividade motora dos animais no campo aberto. Além disso, provamos que os ratos habituaram ao ambiente desse teste, o que significa que a inalação desse tipo de material não provocou variação em termos de aprendizado simples. Uma das causas da alteração no comportamento em relação à motricidade seria o estresse oxidativo causado pelo material particulado no estriado e cerebelo desses animais. Entretanto, em nossa cidade não existem estudos que demonstrem a estreita associação entre inalação de poluentes, estresse oxidativo e alterações comportamentais. Baseados nos nossos trabalhos anteriores e na literatura, nosso objetivo foi investigar se a poluição atmosférica a nível ambiental durante as fases pré e pós-natal alteraria a memória discriminativa de curta-duração e a memória espacial. Além disso, avaliamos o papel do estresse oxidativo como o mecanismo propulsor dessas mudanças de comportamento. Para tal, ratas prenhas foram expostas ao ar filtrado e ao ar não filtrado durante os 21 dias de gestação. Ao final do período de amamentação, os machos foram separados e subdividos em 4 grupos experimentais (n=24): 1) Filtrado: nasceu e viveu em ambiente cujo ar era filtrado, 2) NFF: nasceu em ambiente cujo ar era não filtrado e viveu a partir do 21o dia do pós-natal no ambiente com ar filtrado, 3) FNF: nasceu sob ar filtrado e viveu a partir do 21o dia do pós-natal sob ar não filtrado, 4)NF: nasceu e viveu em ambiente cujo ar era não filtrado. Os animais ficaram expostos a poluição por 150 dias. Os animais foram divididos em 3 lotes: lote 1: n=6 animais por grupo; após anestesia profunda, os animais foram perfundidos com soro fisiológico seguido de paraformaldeído 4%, o encéfalo foi retirado e dissecado em córtex, hipocampo e estriado para análises histológicas por técnicas estereológicas; lote 2: n=12 ratos por grupo; aplicação dos testes comportamentais; um dia após os testes, esses animais foram eutanasiados por decapitação, o encéfalo retirado e dissecado da mesma forma citada anteriormente para análise de estresse oxidativo; lote 3: n=6 animais por grupo; os animais foram decapitados e o sangue troncular coletado para análises de elementos traço tóxicos e essenciais no sangue total. O córtex apresentou lipoperoxidação no grupo NF quando comparado aos outros grupos, assim como uma alta concentração de Cd no sangue. O grupo NFF apresentou uma maior concentração de Cu, Se e Zn no sangue em relação aos demais. Em relação à memória discriminativa de curta-duração, houve uma diminuição no grupo NF em relação aos demais grupos. No hipocampo e estriado, foi observado aumento da lipoperoxidação nos grupos FNF e NF, respectivamente, quando comparado aos outros grupos. Quanto à memória espacial, não houve diferença estatisticamente significativa entre os grupos. Primeiramente, como pudemos observar, o cada estrutura encefálica apresenta uma resposta ao estresse oxidativo. O córtex do grupo NF apresentou aumento de lipoperoxidação. Como se sabe, o Cd é feto tóxico e passa via transplacentária adsorvido ao material particulado inalado pela mãe. No caso do grupo NF, o Cd possivelmente deslocou o Zn do sítio ativo da enzima CuZn superóxido dismutase formando forma inativada da mesma. O Cd, também, forma conjugado com duas moléculas de glutationa reduzida a fim de ser excretado pela bile. Isso reduz a sua capacidade antioxidante. Esse elemento traço desloca o Fe e o Cu dos sítios ativos das suas proteínas de armazenamento, a ferritina e a ceruplasmina, respectivamente. Esses dois elementos ficam livres para catalisar a reação de Fenton cujo produto é o radical hidroxil, extremamente tóxico para o organismo. O grupo NF apresentou uma diminuição na capacidade de discriminar dois objetos diferentes. Provavelmente, o Cd agiu de forma indireta diminuindo a capacidade antioxidante da CuZn superóxido dismutase e da glutationa, além de liberar Fe e Cu e aumentar a produção de radical hidroxil. O aumento da lipoperoxidação causado pelo Cd pode ser o mecanismo responsável pela perda desse tipo de memória. Entretanto, o grupo NFF, cuja exposição à poluição foi na fase pré-natal, não apresentou aumento na lipoperoxidação. Possivelmente, a alta concentração dos elementos traço essenciais, Cu, Zn e Se aumentou a atividade das enzimas CuZn superóxidodismutase e glutationa peroxidase, respectivamente, o que evitou danos oxidativos durante o período intra-uterino. O grupo FNF apresentou aumento de lipoperoxidação no hipocampo, mas não houve diferença na memória espacial testada com o labirinto de Morris modificado. Portanto, considerando todos os achados, concluímos que, possivelmente, o aumento da lipoperoxidação causado indiretamente pelo Cd pode ser um dos mecanismos responsáveis pela perda da capacidade da memória discriminativa de curta-duração. Além disso, os elementos traço essenciais exercem uma proteção via aumento das defesas antioxidantes dos animais que nasceram em ambiente poluído e, após 21 dias de vida, foram transferidos para o ambiente com o ar filtrado, o que demonstra, provavelmente, a existência de mecanismos antioxidantes de adaptação em ambientes inóspitos como forma de proteção contra o agente agressor durante o desenvolvimento do embrião. / Experimental studies done at our laboratory demonstrated that the inhalation of residual oil fly ash by the adult rats decreased motor activity of the animals in the open-field test. Additionaly, we showed that rats which inhalated residual oil fly ash preserved its habituation capacity. In this study, oxidative stress in striatum and cerebellum might be the cause of motor activity alterations. However, there were any studies about air pollution and behavioral alterations in Porto Alegre. Based on our previous works and in the literature, our objective was to investigate if the exposure to air pollution during intrauterine and lactation periods would damage the short term discriminative and spatial memories and if the mechanisms would be dependent of oxidants. For such, female pregnant rats were exposed to the filtered air and to the non filtered air during the 21 days of gestation. At the end of the breast-feeding period, the males were separate and divided in 4 experimental groups (n =24): 1) Filtered (F): - pre and post-natal exposure until adulthood in filtered air; 2) non filtered/filtered air (NFF): pre-natal period in non-filtered air until PND21 and post-natal in filtered air until adulthood; 3) filtered air/non-filtered air (FNF): pre-natal period in filtered air until PND 21 and post-natal period in non-filtered air until adulthood; 4) non filtered air (NF): pre and post-natal periods in non-filtered air.The animals were exposed the pollution for 150 days. The animals were divided in 3 lots: lot 1: n=6 animals per group; after anesthesia, the animals were perfused with saline solution following by paraformaldehyde 4%, the brain was removed and dissected in cortex, hippocampus and striatum for histological analyses by stereological techniques; lot 2: n=12 rats per group; submitted to behavioral tests; one day after the tests, those animals were euthanized by decapitation, the brain was removed and dissected in the same way mentioned previously for oxidative stress analysis; lot 3: 6 animals per group; the animals were decapitated and the troncular blood was collected to analyze the toxic and the essential trace elements. The cortex presented lipoperoxidation in NF group when compared to other groups, as well as a high concentration of Cd in the blood. The group NFF presented higher blood concentration of Cu, Se and Zn when compared to other groups. There was a decrease in the discriminative capacity in the group NF when compared to other groups. In the hippocampus and striatum, increases of lipidperoxidation were observed in the groups FNF and NF, respectively, when compared to other groups. Spatial memory of all groups was preserved. We observed the each brain structure reacts in a different way to oxidative stress. The NF cortex group presented an increased of lipidperoxidation. In this group, there was higher Cd blood concentration, which passes through placenta and it is fetotoxic. It might be possible that Cd dislocated Zn of the active site of CuZn superóxido dismutase resulting in inactive forms of this enzyme. The Cd also depletes reduced glutathione. Moreover, Cd may dislocate the Fe and Cu from its storage proteins to react with oxygen peroxide increasing the hydroxyl radical production by Fenton reaction. The group NF presented a decrease in the capacity to discriminate two different objects. Cd may act in an indirect way reducing the antioxidant capacity of CuZn superxidodismutase and of the glutathione and increasing the hydroxyl radical production. Lipoperoxidation in NF cortex caused by the Cd may be one of the mechanisms which explain the loss of discriminative capacity. However, the group NFF, whose air pollution exposure was in the pre-natal period, did not present increase of lipidperoxidation. The higher concentrations of essential trace elements (Cu, Se and Zn) may protect this group against oxidative stress. These elements are cofactor of antioxidants enzymes, superoxidodismutase and glutathione peroxidase and increased its activities during the intra-uterine exposure to air pollution. The group FNF presented lipidperoxidation increase in the hippocampus, but there was no difference in the spatial memory tested with Morris\' maze. Therefore, considering our data, we suggested that the increase of lipidperoxidation caused indirectly by Cd, which was adsorbed in particulate matter surface, may be one of the mechanisms which explain the loss of short-term discriminative memory