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Caractérisation et impacts des émissions de polluants du transport routier : Apports méthodologiques et cas d'études en Rhône Alpes. / Characterization and impacts of road traffic emissions : Methodology and case of study in Rhônes Alpes.Polo Rehn, Lucie 17 September 2013 (has links)
L'impact des particules fines (PM10-PM2.5) sur la santé a été largement étudié depuis de nombreuses années, notamment pour les sites de proximité automobile. De nombreux dépassements de la valeur limite en PM10 imposée par les directives européennes ont lieu en France et en Europe, en milieu urbain et plus fréquemment en proximité automobile. Les émissions véhiculaires sont une des sources majeures de particules. Ces émissions proviennent à la fois des échappements (TE) mais aussi des émissions hors échappement (TNE) (abrasion des freins, des pneus et de la route, resuspension des poussières de la chaussée dû au déplacement des véhicules…). En France, très peu d'études en proximité automobile ont été effectuées. Les études de déconvolution des sources en France et en Europe s'appuient la plupart du temps sur des parcs automobiles non adaptés (parc américain) ou trop anciens. De plus, seule la source TE est considérée, ce qui sous-estime largement la contribution véhiculaire aux PM10. La meilleure connaissance de la formation, de la caractérisation et de la quantification des particules émises par le trafic est devenue primordiale. L'objectif final étant la détermination des contributions des émissions véhiculaires TE et TNE aux sources primaires de particules, la caractérisation précise de ces sources est primordial. Pour cela, la recherche de traceurs véhiculaires en phases gaz et particulaire a constitué une grosse partie de ce travail. La combinaison de l'étude sur banc à rouleau de cinq véhicules bien représentés dans le parc automobile roulant français et de l'étude effectuée en proximité automobile (Rocade Sud de Grenoble) a constitué le socle de ce travail. Dans la première étude, certains composés chimiques sont apparus comme indicateurs des émissions TE (EC, HAP légers, profils d'alcanes typiques, quelques métaux comme Fe, Cu etc.). Des différences importantes sont observées entre les véhicules diesel sans filtre à particules (FAP) et les véhicules essence et diesel sans FAP. La seconde étude, comparant le site trafic (Grenoble-Echirolles) avec un site de fond urbain (Grenoble- Les Frênes), a mis en évidence certains composés chimiques comme spécifiques des sources TNE et TE sur la base des connaissances acquises avec les mesures sur banc et sur l'enrichissement de certains composés par rapport au site de fond (EC, Cu, Fe, Sn, Mn…). On peut souligner certains enrichissements majeurs comme EC (78%), Cu (82%), Fe (88%), etc. La résolution temporelle a été faite sur une base de 4h, permettant ainsi une caractérisation chimique détaillée en fonction des heures de pointe et "creuses". Une troisième étude, en site trafic également (Grenoble-Le Rondeau) mais sous influence du salage en hiver, est venue compléter nos recherches. Enfin, en nous appuyant sur les résultats de la première partie, nous avons cherché à déconvoluer les sources véhiculaires TE et TNE (Echirolles et Le Rondeau) au moyen d'un modèle statistique d'analyses multivariées, la PMF (Positive Matrix Factorization), apportant ainsi la contribution possible de ces sources aux PM10. Les émissions véhiculaires (TNE+ TE) y contribuent à 34% à Echirolles et à 53% au Rondeau. Quelques incertitudes sont discutées par rapport aux résultats trouvés avec ceux provenant de l'étude géochimique détaillée en première partie. / Fine particles (PM10-P2.5) are recognized to be deleterious to human health particularly in the roadway vicinity. In European countries, and in particular in France, the European daily limit value is exceeded in many sites more than 35 times a year. One of the major sources of fine particles in urban and roadside sites is road traffic. Emissions from road traffic involve exhaust and non-exhaust emissions (resuspension of road dusts, from the brakes, tyres and road-surface-wear, from the corrosion of vehicle components…). Numerous studies have been performed in order to account for exhaust emissions, however not in France. Generally, the profiles used in source apportionment models are not adapted (since they are American profiles) to the French or European fleets. In addition, the contribution of the nonexhaust fraction to total particulate matter (PM) mass is generally not accounted for in the source apportionment results. Therefore, PM10 emissions are underestimated. As a result, better knowledge about formation, characterization and quantification of particles from traffic are becoming necessary. The goals of this work are numerous because ambient air and exhaust emission measurements have been involved. The aim is to accurately discriminate exhaust and nonexhaust sources, in order to provide groundbreaking insights into the contribution and chemical composition of traffic sources. Therefore, the analyses of gas and particle tracers represent a big part of this work. The relationships between the measurements of 5 in-use vehicles well-represented in the French fleet and measurements performed in the vicinity of a suburban highway (southern ring road of Grenoble) have been firstly examined. In the first study, several chemical compounds, organics and inorganics, appeared as tracers of vehicular exhaust (EC, light PAHs, typical alkanes profiles, metals like Fe, Cu etc.). Large differences are noticeable between Diesel vehicles without DPF and petrol vehicles/diesel vehicle retrofitted with a DPF. In the second study, comparison with results from an urban background site (Grenoble-Les Frênes) and from the traffic site (Grenoble-Echirolles) highlighted several specific chemical compounds of exhaust and non-exhaust sources (EC, Cu, Fe, Sn, Mn…). Large increments due to the local traffic have been observed (EC (+78%), Cu (82%), Fe (88%), etc.). The 4-hour temporal resolution allowed for the detailed characterization of chemical species during rush hours and less busy periods. An additional field campaign was performed in another roadside site (Grenoble-Le Rondeau) but in winter during salting conditions. Supplementary information was obtained concerning non-exhaust sources. Finally, thanks to the results from the first part of this work, a Positive Matrix Factorization (PMF) analysis was applied to roadside data (Echirolles and Le Rondeau) in order to discriminate non-exhaust and exhaust traffic sources and to estimate their contribution to PM10. Major contributions for traffic sources (exhaust and non-exhaust) were 34% (Echirolles) and 53% (Le Rondeau). Uncertainties linked to these results are discussed with the results of the first part (detailed chemical study) of this work.
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Metal Particles – Hazard or Risk? Elaboration and Implementation of a Research Strategy from a Surface and Corrosion PerspectiveMidander, Klara January 2009 (has links)
Do metal particles (including particles of pure metals, alloys, metal oxides and compounds) pose a hazard or risk to human health? In the light of this question, this thesis summarizes results from research conducted on metal particles, and describes the elaboration and implementation of an in vitro test methodology to study metal release from particles through corrosion and dissolution processes in synthetic biological media relevant for human exposure through inhalation/ingestion and dermal contact. Bioaccessible metals are defined as the pool of released metals from particles that potentially could be made available for absorption by humans or other organisms. Studies of bioaccessible metals from different metal particles within this thesis have shown that the metal release process is influenced by material properties, particle specific properties, size distribution, surface area and morphology, as well as the chemistry of synthetic biological test media simulating various human exposure scenarios. The presence of metal particles in proximity to humans and the fact that metals can be released from particles to a varying extent is the hazard referred to in the title. The bioavailable metal fraction of the released metals (the fraction available for uptake/absorption by humans through different exposure routes) is usually significantly smaller than the bioaccessible pool of released metals, and is largely related to the chemical form and state of oxidation of the released metals. Chemical speciation measurements of released chromium for instance revealed chromium to be complexed to its non-available form in simulated lung fluids. Such measurements provide an indirect measure of the potential risk for adverse health effects, when performed at relevant experimental conditions. A more direct way to assess risks is to conduct toxicological in-vitro testing of metal particles, for instance on lung cell cultures relevant for human inhalation. Induced toxicity of metal particles on lung cells includes both the effect of the particles themselves and of the released metal fraction (including bioaccessible and bioavailable metals), the latter shown to be less predominant. The toxic response was clearly influenced by various experimental conditions such as sonication treatment of particles and the presence of serum proteins. Thorough characterization of metal particles assessing parameters including chemical surface composition, degree of agglomeration in solution, size distribution, surface area and morphology was performed and discussed in relation to generated results of bioaccessibility, bioavailability and induced toxicity. One important conclusion was that neither the surface composition nor the bulk composition can be used to assess the extent of metals released from chromium-based alloy particles. These findings emphasize that information on physical-chemical properties and surface characteristics of particles is essential for an in-depth understanding of metal release processes and for further use and interpretation of bioaccessibility data to assess hazard and reduce any risks induced by human exposure to metal particles. / QC 20100803
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Aplicação de Bunodosoma Caissarum e Perna Perna para estudos de biomonitoramento de metais: caracterização da bioacumulação em microcosmos e dinâmica espacial na Baía de GuanabaraAnsari, Nafisa Rizzini 20 September 2016 (has links)
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Tese Nafisa Rizzini Ansari.pdf: 8620069 bytes, checksum: 16d148c878ee2d9445629dc9780642f5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências - Geoquímica. Niterói, RJ / Os objetivos do presente estudo foram avaliar a anêmona-do-mar Bunodosoma
caissarum como espécie biomonitora da contaminação por metais para a Baía de
Guanabara (Rio de Janeiro, Brasil) e a região insular adjacente, comparando-a com
uma espécie tradicionalmente utilizada na região: o mexilhão Perna perna; além de
investigar a bioacumulação de Cd, Hg e Zn por B. caissarum e P. perna por meio de
experimentos de incubação em laboratório. A Baía de Guanabara é uma baía eutrófica
contaminada por diversos metais. A região insular adjacente é considerada menos
impactada por metais, porém esta é influenciada por aportes antrópicos, como os
efluentes dos emissários submarinos e a disposição de material dragado em locais
próximos a esta região. Bivalves, como o P. perna, são amplamente utilizados para o
biomonitoramento de metais na Baía de Guanabara. No entanto, a anêmona B.
caissarum pode ser uma alternativa em ambientes onde os mexilhões não são
abundantes ou não existem. Neste estudo, mediram-se as concentrações de metais
nos tecidos de B. caissarum e P. perna amostrados na Baía de Guanabara e na região
insular adjacente em 2013 e estas foram comparadas com concentrações medidas
nos mesmos locais em 2009. Os elementos Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sn,
Ti, V e Zn foram determinados por espectrometria de massa com fonte de plasma
indutivamente acoplado (ICP-MS). Foi observada uma grande variabilidade espacial
e temporal nas concentrações dos metais nos tecidos de B. caissarum e P. perna. No
entanto, ambas as espécies foram capazes de bioacumular todos os elementos
estudados. Devido à abundância de B. caissarum na área de estudo e a sua
capacidade de bioacumular os metais estudados, sugere-se seu uso como biomonitor
de metais e seu potencial uso como biomonitor complementar para estudos de
biomonitoramento com mais de uma espécie de invertebrado, como P. perna. Com
esta finalidade, deve-se estudar melhor as características de bioacumulação de
metais de interesse ambiental e ecotoxicológico, como Hg, Cd e Zn, por B. caissarum
para possibilitar seu uso. Com este intuito, realizaram-se incubações com Hg, Cd e
Zn em microcosmos com B. caissarum e P. perna. Os espécimes foram incubados
com isótopos destes metais em aquários e as concentrações foram monitoradas
durante o período de incubação. O experimento com Hg investigou como B. caissarum
afeta a distribuição, metilação e volatilização de Hg adicionando-se o radiotraçador
203Hg a microcosmos com e sem B. caissarum. Mediu-se o Hg total e o metilmercúrio
(MeHg) por espectrometria gama e cintilação líquida respectivamente. Os espécimes
apresentaram um fator de bioconcentração de 70. Observou-se a produção de MeHg
em todos os microcosmos e uma maior volatilização de Hg nos microcosmos com B.
caissarum. Nos experimentos com Cd e Zn, spikes enriquecidos em 116Cd ou 68Zn
foram adicionados aos microcosmos com B. caissarum ou P. perna e as
concentrações foram medidas através do monitoramento de razões isotópicas. Os
fatores de bioconcentração para B. caissarum e P. perna expostos a 0,9 μg L-1 de
116Cd foram respectivamente 80,5 e 850 e em espécimes expostos a 1,4 μg L-1, 6,9
μg L-1 e 34,7 μg L-1 de 68Zn foram respectivamente 243, 398 e 340 em B. caissarum e
1789, 1238 e 621 em P. perna. As proteínas citosólicas associadas ao Cd e ao Zn
foram extraídas dos tecidos dos espécimes incubados e analisadas por cromatografia
de exclusão por tamanho e espectrometria de massa com fonte de plasma
indutivamente acoplado. Frações citosólicas associadas ao Cd e ao Zn foram
detectadas em ambas as espécies. Em todos os experimentos B. caissarum expeliu
secreções mucosas que continham os isótopos adicionados. Estes estudos
possibilitaram uma melhor compreensão das características de bioacumulação de Hg,
Cd e Zn pelas espécies estudadas e fornecem subsídios para sua aplicação em
estudos de biomonitoramento destes metais. / The objectives of this study were to evaluate the sea anemone Bunodosoma
caissarum as a biomonitor species for metal contamination in Guanabara Bay (Rio de
Janeiro, Brazil) and an adjacent island region, by comparing it with another species
traditionally used in the region: the mussel Perna perna. It was also to investigate the
uptake of Cd, Hg and Zn through laboratory incubation experiments with both species.
Guanabara Bay is an eutrophic bay contaminated by several metals. The adjacent
island region is considered less impacted by metals, although that region is influenced
by anthropic inputs, such as the effluents of submarine outfalls and the disposal of
dredged material from surrounding sites. Bivalves, such as P. perna, are widely used
for biomonitoring metal contamination in Guanabara Bay. However the sea anemone
B. caissarum can be an alternative in sites where the mussels are not abundant or do
not exist. In this study, metal concentrations were measured in the tissues of B.
caissarum and P. perna sampled in Guanabara Bay and adjacent islands in 2013 and
were compared to previous measurements in the same sites in 2009. The elements
Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sn, Ti, V and Zn were determined by inductively
coupled plasma-mass spectrometry (ICP-MS). There was a great spatial and temporal
variability of metal concentrations in the tissues of B. caissarum and P. perna. Yet both
species were able to bioaccumulate all the studied elements. Due to the abundance of
B. Caissarum in the studied area and its capacity to bioaccumulate the studied
elements, its use as a biomonitor of metals is suggested and its potential use as a
complementary biomonitor. For this purpose, it is necessary to better understand the
bioaccumulation characteristics of metals of environmental and ecotoxicological
concern by B. caissarum. So, incubations were carried out with Hg, Cd and Zn in
microcosms with B. caissarum and P. perna. Specimens were incubated with isotopes
of these metals in aquariums and concentrations were monitored during an incubation
period. The Hg experiment investigated how B. caissarum affects Hg distribution,
methylation and volatilization by adding the radiotracer 203Hg to microcosms with and
without the sea anemone. Total Hg and methylmercury (MeHg) were measured
respectively by gamma spectrometry and liquid scintillation. Specimens presented a
bioconcentration factor of 70. There was MeHg production in all microcosms and a
higher Hg volatilization occurred in microcosms with B. caissarum. In Cd and Zn
experiments, enriched 116Cd or 68Zn spikes were added to microcosms with B.
caissarum or P. perna and concentrations were measured by monitoring isotope ratios.
Bioconcentration factors for B. caissarum and P. perna exposed to 0.9 μg L-1 of 116Cd
were respectively 80.5 and 850. In specimens exposed to 1.4 μg L-1, 6.9 μg L-1 and
34.7 μg L-1 of 68Zn those factors were respectively 243, 398 and 340 in B. caissarum
and 1789, 1238 and 621 for P. perna. Cytosolic proteins associated with Cd and Zn
from the tissues of the incubated specimens were extracted and analyzed by sizeexclusion
chromatography and inductively coupled plasma-mass spectrometry. Cd
and Zn-accumulating cytosolic fractions were detected in both species. In all
experiments B. caissarum expelled mucus secretions that contained the added
isotopes. These studies enabled a better understanding of the bioaccumulation
characteristics of Hg, Cd and Zn by the studied species and can contribute to their use
in biomonitoring studies with these metals.
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