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Mise en place d'une mesure rapide de la composition chimique de l'aérosol en zone urbaine : étude en mégapolesD'Argouges, Odile 06 November 2009 (has links) (PDF)
L'augmentation continue de la population urbaine s'accompagne d'une augmentation de la taille des villes et de l'apparition de mégapoles, particulièrement en Asie du sud-est. Ces agglomérations sont des sources intenses de pollution et en particulier de particules atmosphériques. Pour en étudier les différents impacts (sur le climat, l'environnement ou la santé) il est important de documenter les sources et les transformations rapides des polluants, ce que permettent les mesures en temps quasi-réel de leur composition chimique. C'est dans ce cadre que ce travail de thèse se propose de développer et qualifier un parc instrumental de terrain capable de documenter la chimie de l'aérosol sur des pas de temps court (au moins horaires). Cet ensemble permet la mesure des ions majeurs par technique PILS (Particle-Into-Liquid-Sampler), de la fraction carbonée (EC-OC) par technique thermo-optique (EC-OC Sunset Field Analyzer) et celle de la fraction organique hydrosoluble également par technique PILS. La masse totale de l'aérosol est obtenue sans artefact avec un TEOM-FDMS. L'optimisation et la qualification des instruments sont abordées, et le potentiel du parc (à différents stades de son développement) est évalué à partir de résultats obtenus pour les mégapoles contrastées Paris (Mai-Juin 2007) et Pékin (Août 2007). Cet ensemble instrumental permet de reconstruire la masse (PM2.5) et les propriétés optiques des aérosols sur des pas de temps horaires, d'aider à l'identification et à la déconvolution des sources d'aérosols (sources locales/régionales ou primaires/secondaires) ainsi que d'affiner la connaissance de l'aérosol organique à travers sa fraction insoluble/soluble.
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Characterization and source apportionment of PM2.5 in the Southeastern United StatesLee, Sangil 07 November 2006 (has links)
Fine particulate matter (PM2.5) affects the environment in a variety of ways, including of human health, visibility impairment, acid deposition, and climate change. As of March, 2006, 47 counties are designated as non-attainment areas in terms of PM2.5 in the southeastern United States. State agencies with PM2.5 non-attainment counties must develop plans that demonstrate how they will achieve attainment status. State agencies also have to address emission sources of visibility impairment and develop strategies to improve visibility. It is essential to understand PM2.5 composition and sources in order to develop effective control strategies to reduce PM2.5. In this thesis, actual prescribed burning emissions were characterized for better estimation of their impacts on air quality. Chemical mass balance (CMB) modeling, a receptor-oriented source apportionment technique, was applied to understand regional characteristics of PM2.5 source impacts in the Southeast. Uncertainty issues in the CMB source apportionment results due to both poor spatial representativeness and measurement errors was addressed for better understanding and estimation of the uncertainties. Possible future research is recommended based on the findings in this thesis.
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Measurement and analysis of ambient atmospheric particulate matter in urban and remote environmentsHagler, Gayle S. W. 09 May 2007 (has links)
Atmospheric particulate matter pollution is a challenging environmental concern in both urban and remote locations worldwide. It is intrinsically difficult to control, given numerous anthropogenic and natural sources (e.g. fossil fuel combustion, biomass burning, dust, and seaspray) and atmospheric transport up to thousands of kilometers after production. In urban regions, fine particulate matter (particles with diameters under 2.5 m) is of special concern for its ability to penetrate the human respiratory system and threaten cardiopulmonary health. A second major impact area is climate, with particulate matter altering Earth s radiative balance through scattering and absorbing solar radiation, modifying cloud properties, and reducing surface reflectivity after deposition in snow-covered regions. While atmospheric particulate matter has been generally well-characterized in populated areas of developed countries, particulate pollution in developing nations and remote regions is relatively unexplored. This thesis characterizes atmospheric particulate matter in locations that represent the extreme ends of the spectrum in terms of air pollution the rapidly-developing and heavily populated Pearl River Delta Region of China, the pristine and climate-sensitive Greenland Ice Sheet, and a remote site in the Colorado Rocky Mountains. In China, fine particles were studied through a year-long field campaign at seven sites surrounding the Pearl River Delta. Fine particulate matter was analyzed for chemical composition, regional variation, and meteorological impacts. On the Greenland Ice Sheet and in the Colorado Rocky Mountains, the carbonaceous fraction (organic and elemental carbon) of particulate matter was studied in the atmosphere and snow pack. Analyses included quantifying particulate chemical and optical properties, assessing atmospheric transport, and evaluating post-depositional processing of carbonaceous species in snow.
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Engineering approaches to address erros in measured and predicted particulate matter concentrationsWanjura, John David 16 August 2006 (has links)
Some of the air pollution regulations in the United States are based on an
application of the National Ambient Air Quality Standards at the property line.
Agricultural operations such as cotton gins, feed mills, and cattle feed yards may be
inappropriately regulated by such regulations if the current methods of measuring and
predicting the concentrations of regulated pollutants are used. The regulated particulate
matter pollutants are those with aerodynamic equivalent diameters less than or equal to a
nominal 10 and 2.5 micrometers (PM10 and PM2.5) respectively.
The current Federal Reference Method PM10 and PM2.5 samplers exhibit oversampling
errors when sampling dusts with particle size distributions similar to those of
agricultural sources. These errors are due to the interaction of the performance
characteristics of the sampler with the particle size distribution of the dust being
sampled. The results of this work demonstrate the development of a new sampler that
may be used to accurately sample total suspended particulate (TSP) concentrations. The
particle size distribution of TSP samples can be obtained and used to more accurately
determine PM10 and PM2.5 concentrations. The results of this work indicate that accurate
measures of TSP can be taken on a low volume basis. This work also shows that the low
volume samplers provide advantages in maintaining more consistent sampling flow
rates, and more robust measurements of TSP concentrations in high dust concentrations.
The EPA approved dispersion model most commonly used to estimate
concentrations downwind from a stationary source is the Industrial Source Complex
Short Term version 3 (ISCST3). ISCST3 is known to over-predict downwind
concentrations from low level point sources. The results of this research show that the
magnitude of these errors could be as much as 250%. A new approach to correcting
these errors using the power law with P values as a function of stability class and
downwind distance is demonstrated. Correcting the results of ISCST3 using this new
approach results in an average estimated concentration reduction factor of 2.3.
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Improving aerosol simulations: assessing and improving emissions and secondary organic aerosol formation in air quality modelingBaek, Jaemeen 21 August 2009 (has links)
Both long-term and short-term exposure to fine particulate matter (PM2.5) has been shown to increase the rate of respiratory and cardiovascular illness, premature death, and hospital admissions from respiratory causes. It is important to understand what contributes to ambient PM2.5 level to establish effective regulation, and air quality model can provide guidance based on the best scientific understanding available. However, PM2.5 simulations in air quality models have often found performance less than desirable, particularly for organic carbon levels. Here, some of major shortcomings of current air quality model will be addressed and improved by using CMAQ, receptor models, and regression analysis. Detailed source apportionment of PM2.5 performed using the CMAQ-tracer method suggests that wood combustion and mobile sources are the largest sources of PM2.5, followed by meat cooking and industrial processes. Biases in emission estimates are investigated using tracer species, such as organic molecular markers and trace metals that are used in receptor models. Comparison of simulated and observed tracer species shows some consistent discrepancies, which enables us to quantify biases in emissions and improve CMAQ simulations. Secondary organic aerosol (SOA) is another topic that is investigated. CMAQ studies on organic aerosol usually underestimate organic carbon with larger than a 50% bias. Formation of aged aerosol from multigenerational semi-volatile organic carbon is added to CMAQ, significantly improving performance of organic aerosol simulations.
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Errors associated with particulate matter measurements on rural sources: appropriate basis for regulating cotton ginsBuser, Michael Dean 30 September 2004 (has links)
Agricultural operations across the United States are encountering difficulties complying with current air pollution regulations for particulate matter (PM). PM is currently regulated in terms of particle diameters less than or equal to a nominal 10 μm (PM10); however, current legislation is underway to regulate PM with diameters less than or equal to a nominal 2.5 μm (PM2.5). The goals of this research were to determine the biases and uncertainties associated with current PM10 and PM2.5 sampling methods and to determine the extent to which these errors may impact the determination of cotton gin emission factors.
Ideally, PM samplers would produce an accurate measure of the pollutant indicator; for instance, a PM10 sampler would produce an accurate measure of PM less than or equal to 10 μm. However, samplers are not perfect and errors are introduced because of the established tolerances associated with sampler performance characteristics and the interaction of particle size and sampler performance characteristics. Results of this research indicated that a source emitting PM characterized by a mass median diameter (MMD) of 20 μm and a geometric standard deviation (GSD) of 1.5 could be forced to comply with a 3.2 and 14 times more stringent regulation of PM10 and PM2.5, respectively, than a source emitting PM characterized by a MMD of 10 μm and a GSD of
1.5. These estimates are based on both sources emitting the same concentrations of true PM or concentrations corresponding to the particle diameters less than the size of interest.
Various methods were used to estimate the true PM10 and PM2.5 emission factors associated with cotton gin exhausts and the extent to which the sampler errors impacted the PM regulation. Results from this research indicated that current cotton gin emission factors could be over-estimated by about 40%. This over-estimation is a consequence of the relatively large PM associated with cotton gin exhausts. These PM sampling errors are contributing to the misappropriation of source emissions in State Implementation Plans, essentially forcing Air Pollution Regulatory Agencies to require additional controls on sources that may be incorrectly classified has high emitters.
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Characterization of Polycyclic Aromatic Hydrocarbons (PAH) in airborne particles and assessment of human exposure to PAHsLi, Zheng 31 March 2009 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are a group of toxic air pollutants formed during incomplete combustion and are ubiquitously distributed in the environment. To determine particle-bound PAHs in archived PM2.5 samples taken with low flow rate in Atlanta, a sensitive and robust method was developed for measuring 28 PAHs and methyl PAHs in PM samples using isotope dilution gas chromatography/high resolution mass spectrometry (GC/HRMS). The method was then used to analyze PM2.5 samples collected at three sites (rural, urban, suburban-highway) from the Assessment of Spatial Aerosol Composition in Atlanta (ASACA) network. Distinct seasonal and spatial variations were observed in PAH concentration. Particle-bound PAH levels were significantly higher in winter than in summer. The suburban-highway site had higher PM2.5-bound PAH concentration than did the urban site, and the rural site had the lowest PAH levels. Retene, a proposed biomass burning tracer, captured both the high leaves-grasses-bushes-branches burning season and the high wood burning months, suggesting that it might be a better marker for all biomass burning, while potassium ion might be a more specific tracer for wood burning. Human exposure to PAHs can be assessed by characterizing their hydroxy PAH (OH-PAH) metabolites in urine samples. A method was developed to measure 24 urinary OH-PAHs, metabolites of 8 parent PAHs, using enzymatic de-conjugation, automatic liquid-liquid extraction, and GC/HRMS. A study was then carried out to evaluating the variability of the urinary biomarker levels in a non-occupationally exposed non-smoking reference group. Levels of urinary PAH metabolites varied widely both within-subject and between-subjects and the within-day variance far exceeded the between-day variance. There were also considerable temporal correlations for these biomarkers. Sample size calculations were conducted and taking 24-hour voids would require the least number of subjects, which should be considered during epidemiological study design. Finally, a study was conducted to evaluate exposure to ambient PAHs in an urban setting among 8 non-occupationally exposed non-smoking volunteers employing both personal air sampling and urine biomonitoring. PAH levels varied largely in air samples taken at home, at work, and while driving or jogging. Monitoring urinary OH-PAH levels can capture both inhalation and dietary exposures. Total inhaled PAH was correlated with total excreted OH-PAHs, suggesting that by combining personal air sampling and biomonitoring, exposure to environmental PAHs can be well characterized even for low-level exposure.
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Caracterização de área de referência para material particulado inalável (MP2,5) associado a biomonitoramento genético em criançasSilva, Cristiane Silva da January 2013 (has links)
As emissões veiculares e as atividades industriais, além de outras relacionadas ao crescimento da população humana, têm gerado uma grande variedade de compostos genotóxicos e/ou carcinogênicos, que podem ser liberados no ar e causar danos à saúde. Os níveis e os tipos de poluentes podem variar de acordo com a região. Entre os indicadores de poluição, as partículas finas inaláveis (MP2,5) podem atingir os alvéolos pulmonares e causar problemas respiratórios, especialmente em crianças, grupo mais sensível a substâncias tóxicas do que adultos. Nesse sentido, o objetivo deste estudo foi caracterizar área de referência para material particulado inalável (MP2,5), através de biomarcadores genéticos e dosagens de hidrocarbonetos policíclicos aromáticos (HPAs), associados ao biomonitoramento genético de crianças. O trabalho foi realizado no município de Santo Antônio da Patrulha, RS, Brasil, área livre da pluma de dispersão de contaminantes industriais, classificada em estudos anteriores como área de referência. Os extratos orgânicos obtidos em nove pools de amostras foram avaliados quanto à mutagenicidade através do ensaio Salmonella/microssoma, método de microssuspensão, com as linhagens TA98, TA100, YG1024 (em presença e ausência de metabolização) e YG1021 (sem metabolização). Os pools de amostras de ar foram quantificados quanto aos HPAs considerados poluentes prioritários. Para o biomonitoramento das 45 crianças avaliadas, foram utilizados os ensaios cometa em sangue periférico e micronúcleo (MN) em mucosa oral para medir lesões genômicas precoces. A concentração de MP2,5 no período, apresentou 9% (entre 25,89 e 64,71 μg/m3) de eventos acima do recomendado pela Organização Mundial de Saúde (25 μg/m3). Foram obtidos resultados, em revertentes/m3, para a mutagênese, de negativos no período da primavera a 8,3±0,69 no outono (-S9) e de negativos na primavera a 5,4±0,36 no inverno (+S9) para a linhagem TA98. Os resultados com as linhagens YG mostraram a presença de compostos nitrogenados com prevalência de mononitroarenos e aminas aromáticas. Entre os HPAs, o benzo(g,h,i)perileno apresentou a maior concentração em todas as amostras na área de estudo, seguido do indeno(1,2,3-cd)pireno (1,73 ng/m³ e 1,17 ng/m³, respectivamente). Em relação ao biomonitoramento das 45 crianças avaliadas, não houve correlação entre os parâmetros do ensaio cometa (momento, intensidade e comprimento da cauda) e os do teste do micronúcleo. Os valores observados para crianças em relação a estes biomarcadores foram: 0,27±0,407 para indução de MN em células bucais e 0,56±0,727 para brotos nucleares, 0,51±0,694 para células binucleadas, 46,37±16,330 para cromatina condensada, 6,97±5,746 para picnose, 6,60±5,540 para cariólise e 57,55±24,920 para cariorréxe, suas variantes celulares (‰); para respostas ao ensaio cometa em relação ao comprimento da cauda (23,07±12,442), intensidade da cauda (7,28±11,657) e momento da cauda (0,95±2,30). A análise tanto para o teste do MN quanto para o ensaio cometa relacionada ao sexo e à idade não foi significativa. Entre os fatores de confusão, foram observadas diferenças significativas entre o fumo passivo e indução de MN. A presença de HPAs e a resposta mutagênica podem estar relacionadas às emissões veiculares locais. Estes resultados evidenciam a importância de se estudar áreas de referência para poluição atmosférica, estabelecendo níveis basais, principalmente em populações de crianças. / Vehicular emissions and industrial activities and others involving the growth of the human population have caused a great variety of genotoxic and/or carcinogenic compounds, which may be released into the air and be harmful to health. The levels and types of pollutants may vary according to the region. Among the indicators of pollution fine inhalable particles (PM2.5) can reach the pulmonary alveoli and cause respiratory problems, especially in children, a group that is more sensitive to toxic substances than adults. In this sense, the purpose of this study was to characterize an area of reference for inhalable particulate material (PM2.5), through genetic biomarkers and polycyclic aromatic hydrocarbon (PAHs) dosages, associated with the genetic biomonitoring of children. It was performed in the city of Santo Antônio da Patrulha, RS, Brazil, an area that is free from the industrial pollutant contamination plume, classified in previous studies as an area of reference. The organic extracts obtained in nine pools of samples were evaluated for mutagenicity through the Salmonella/microsome assay, microsuspension method, with TA98, TA100, YG1024 (in the presence and absence of metabolization) and YG1021 (without metabolization). The pools of air samples were quantified as to the PAHs considered priority pollutants. In order to bio monitor the 45 children evaluated, the Comet assays in peripheral blood and mincronucleus (MN) in oral mucosa were used to measure early genomic lesions. The concentration of PM2.5 during the period, obtained 9% (between 25.89 and 64.71 μg/m3) of the values above that recommended by the World Health Organization (25 μg/m3). Results were obtained in revertants/m3, for the mutagenesis, of negatives during the spring to 8.3±0.69 in autumn (-S9) and of negative in spring to 5.4±0.36 in winter (+S9) for strain TA98. The results with strains YG showed the presence of nitrogenated compounds with a prevalence of mononitroarenes and aromatic amines. Among the PAHs , benzo(g,h,i)perylene presented the highest concentration in all samples in the area of study followed by indeno(1,2,3-cd) pyrene (1.73 ng/m³ and 1.17 ng/m³, respectively). As to the biomonitoring of the 45 children evaluated there was no correlation between the parameters of the comet assay (moment, intensity and tail length) and the micronucleus test. The values reported for children concerning these biomarkers were: 0.27±0.407 for induction of MN in buccal cells and 0.56±0.727 for nuclear buds, 0.51±0.697 for binucleated cells, 46.37±16.330 for condensed chromatin, 6.97±5.746 for picnosis, 6.60±5.540 for caryolysis and 57.55±24.920 for caryorrhexis, its cellular variants (‰), and for responses to the Comet assay in relation to the tail length (23.07±12.442), intensity of the tail (7.28±11.657) and moment of the tail (0.95±2,30). The analysis both for the MN test and for the Comet assay regarding sex and age was not significant. Among the counfounding factors, significant differences were observed for the passive smoking and induction of MN. The presence of PAHs and the mutagen response may be related to the local vehicular emissions. These results show the importance of studying areas of reference for atmospheric pollution, establishing baseline levels, especially in populations of children.
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Vliv emisí prachových částic a pachových látek z intenzivního výkrmu drůbeže na životní prostředí v okolí chovu.COUFAL, Marek January 2018 (has links)
This thesis is about evaluation of the influence of odorus substances and dust particles from intensive poultry farming to the environment. Measurement was done on a family farm near the forest in spring and autumn in 2017. The fattening of broilers is carried out there in four fattening halls with a total of 103,000 units. Poultry is fattened on the farm for 238 days during the whole calendar year after 7 batches. Sampling was carried out from one of these halls. The values obtained are ranged from 59 / m3 to 215 / m3 for odorous substances and particulate matter PM10 ranging from 0.061 mg to 0.0765 mg. PM2.5 dust particles showed values of 0.042 mg after 0.1535 mg. Evaluation of odorous substances was performed by the method of dynamic olfactometry according to the standard ČSN EN 13 725. The values obtained were ranged from 59 / m3 to 215 / m3. The range of production specific emissions was between 0.013828 and 0.298366 ( / / s). The PM10 particle emission production rate between 0,0000179 and 0,0001094 (mg / pc / year) and PM2,5 from 0,0000642 to 0,0001672 (mg / pc / year) was determined using the particulate measurement methodology. These data were compared with the relevant air pollution limits according to Annex No. 1 to the Act on Air Protection No.201 / 2012 Coll., Immission background in the locality and a dispersion study was prepared for them.
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Caracterização de área de referência para material particulado inalável (MP2,5) associado a biomonitoramento genético em criançasSilva, Cristiane Silva da January 2013 (has links)
As emissões veiculares e as atividades industriais, além de outras relacionadas ao crescimento da população humana, têm gerado uma grande variedade de compostos genotóxicos e/ou carcinogênicos, que podem ser liberados no ar e causar danos à saúde. Os níveis e os tipos de poluentes podem variar de acordo com a região. Entre os indicadores de poluição, as partículas finas inaláveis (MP2,5) podem atingir os alvéolos pulmonares e causar problemas respiratórios, especialmente em crianças, grupo mais sensível a substâncias tóxicas do que adultos. Nesse sentido, o objetivo deste estudo foi caracterizar área de referência para material particulado inalável (MP2,5), através de biomarcadores genéticos e dosagens de hidrocarbonetos policíclicos aromáticos (HPAs), associados ao biomonitoramento genético de crianças. O trabalho foi realizado no município de Santo Antônio da Patrulha, RS, Brasil, área livre da pluma de dispersão de contaminantes industriais, classificada em estudos anteriores como área de referência. Os extratos orgânicos obtidos em nove pools de amostras foram avaliados quanto à mutagenicidade através do ensaio Salmonella/microssoma, método de microssuspensão, com as linhagens TA98, TA100, YG1024 (em presença e ausência de metabolização) e YG1021 (sem metabolização). Os pools de amostras de ar foram quantificados quanto aos HPAs considerados poluentes prioritários. Para o biomonitoramento das 45 crianças avaliadas, foram utilizados os ensaios cometa em sangue periférico e micronúcleo (MN) em mucosa oral para medir lesões genômicas precoces. A concentração de MP2,5 no período, apresentou 9% (entre 25,89 e 64,71 μg/m3) de eventos acima do recomendado pela Organização Mundial de Saúde (25 μg/m3). Foram obtidos resultados, em revertentes/m3, para a mutagênese, de negativos no período da primavera a 8,3±0,69 no outono (-S9) e de negativos na primavera a 5,4±0,36 no inverno (+S9) para a linhagem TA98. Os resultados com as linhagens YG mostraram a presença de compostos nitrogenados com prevalência de mononitroarenos e aminas aromáticas. Entre os HPAs, o benzo(g,h,i)perileno apresentou a maior concentração em todas as amostras na área de estudo, seguido do indeno(1,2,3-cd)pireno (1,73 ng/m³ e 1,17 ng/m³, respectivamente). Em relação ao biomonitoramento das 45 crianças avaliadas, não houve correlação entre os parâmetros do ensaio cometa (momento, intensidade e comprimento da cauda) e os do teste do micronúcleo. Os valores observados para crianças em relação a estes biomarcadores foram: 0,27±0,407 para indução de MN em células bucais e 0,56±0,727 para brotos nucleares, 0,51±0,694 para células binucleadas, 46,37±16,330 para cromatina condensada, 6,97±5,746 para picnose, 6,60±5,540 para cariólise e 57,55±24,920 para cariorréxe, suas variantes celulares (‰); para respostas ao ensaio cometa em relação ao comprimento da cauda (23,07±12,442), intensidade da cauda (7,28±11,657) e momento da cauda (0,95±2,30). A análise tanto para o teste do MN quanto para o ensaio cometa relacionada ao sexo e à idade não foi significativa. Entre os fatores de confusão, foram observadas diferenças significativas entre o fumo passivo e indução de MN. A presença de HPAs e a resposta mutagênica podem estar relacionadas às emissões veiculares locais. Estes resultados evidenciam a importância de se estudar áreas de referência para poluição atmosférica, estabelecendo níveis basais, principalmente em populações de crianças. / Vehicular emissions and industrial activities and others involving the growth of the human population have caused a great variety of genotoxic and/or carcinogenic compounds, which may be released into the air and be harmful to health. The levels and types of pollutants may vary according to the region. Among the indicators of pollution fine inhalable particles (PM2.5) can reach the pulmonary alveoli and cause respiratory problems, especially in children, a group that is more sensitive to toxic substances than adults. In this sense, the purpose of this study was to characterize an area of reference for inhalable particulate material (PM2.5), through genetic biomarkers and polycyclic aromatic hydrocarbon (PAHs) dosages, associated with the genetic biomonitoring of children. It was performed in the city of Santo Antônio da Patrulha, RS, Brazil, an area that is free from the industrial pollutant contamination plume, classified in previous studies as an area of reference. The organic extracts obtained in nine pools of samples were evaluated for mutagenicity through the Salmonella/microsome assay, microsuspension method, with TA98, TA100, YG1024 (in the presence and absence of metabolization) and YG1021 (without metabolization). The pools of air samples were quantified as to the PAHs considered priority pollutants. In order to bio monitor the 45 children evaluated, the Comet assays in peripheral blood and mincronucleus (MN) in oral mucosa were used to measure early genomic lesions. The concentration of PM2.5 during the period, obtained 9% (between 25.89 and 64.71 μg/m3) of the values above that recommended by the World Health Organization (25 μg/m3). Results were obtained in revertants/m3, for the mutagenesis, of negatives during the spring to 8.3±0.69 in autumn (-S9) and of negative in spring to 5.4±0.36 in winter (+S9) for strain TA98. The results with strains YG showed the presence of nitrogenated compounds with a prevalence of mononitroarenes and aromatic amines. Among the PAHs , benzo(g,h,i)perylene presented the highest concentration in all samples in the area of study followed by indeno(1,2,3-cd) pyrene (1.73 ng/m³ and 1.17 ng/m³, respectively). As to the biomonitoring of the 45 children evaluated there was no correlation between the parameters of the comet assay (moment, intensity and tail length) and the micronucleus test. The values reported for children concerning these biomarkers were: 0.27±0.407 for induction of MN in buccal cells and 0.56±0.727 for nuclear buds, 0.51±0.697 for binucleated cells, 46.37±16.330 for condensed chromatin, 6.97±5.746 for picnosis, 6.60±5.540 for caryolysis and 57.55±24.920 for caryorrhexis, its cellular variants (‰), and for responses to the Comet assay in relation to the tail length (23.07±12.442), intensity of the tail (7.28±11.657) and moment of the tail (0.95±2,30). The analysis both for the MN test and for the Comet assay regarding sex and age was not significant. Among the counfounding factors, significant differences were observed for the passive smoking and induction of MN. The presence of PAHs and the mutagen response may be related to the local vehicular emissions. These results show the importance of studying areas of reference for atmospheric pollution, establishing baseline levels, especially in populations of children.
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