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Obesity is currently one of the most alarming pathological conditions due to the progressive increase in its prevalence. In the last decade, it has been associated with fine particulate matter suspended in the air (PM2.5). The purpose of this study was to explore the mechanistic interaction of PM2.5 with a high-fat diet (HFD) through the differential regulation of transcriptional signatures, aiming to identify the association of these particles with metabolically abnormal obesity. The research design was observational, using bioinformatic methods and an explanatory approach based on Rothman's causal model. We propose three new transcriptional signatures in murine adipose tissue. The sum of transcriptional differences between the group exposed to an HFD and PM2.5, compared to the control group, were 0.851, 0.265, and -0.047 (p > 0.05). The HFD group increased body mass by 20% with two positive biomarkers of metabolic impact. The group exposed to PM2.5 maintained a similar weight to the control group but exhibited three positive biomarkers. Enriched biological pathways (p < 0.05) included PPAR signaling, small molecule transport, adipogenesis genes, cytokine-cytokine receptor interaction, and HIF-1 signaling. Transcriptional regulation predictions revealed CpG islands and common transcription factors. We propose three new transcriptional signatures: FAT-PM2.5-CEJUS, FAT-PM2.5-UP, and FAT-PM2.5-DN, whose transcriptional regulation profile in adipocytes was statistically similar by dietary intake and HFD and exposure to PM2.5 in mice; suggesting a mechanistic interaction between both factors. However, HFD-exposed murines developed moderate metabolically abnormal obesity, and PM2.5-exposed murines developed severe abnormal metabolism without obesity. Therefore, in Rothman's terms, it is concluded that HFD is a sufficient cause of the development of obesity, and PM2.5 is a component cause of severe abnormal metabolism of obesity. These signatures would be integrated into a systemic biological process that would induce transcriptional regulation in trans, activating obesogenic biological pathways, restricting lipid mobilization pathways, decreasing adaptive thermogenesis and angiogenesis, and altering vascular tone thus inducing a severe metabolically abnormal obesity.

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Preterm deliveries are a major multifactorial public health problem in French Guiana. Desert dust episodes have been associated with preterm delivery in Guadeloupe, a territory with similarities to French Guiana. We thus tried to replicate this finding in the context of French Guiana. A retrospective ecological cohort study combined daily PM10 concentration measurements during pregnancy and term at delivery extracted from French Guiana's computerized pregnancy delivery registry. Daily PM10 concentrations during the course of pregnancy were analyzed as mean concentrations and as the proportion of intense dust episodes (≥55 µg PM10/m3). These exposure variables were studied in relation to the outcome of preterm delivery. Overall, 3,321 pregnant women with complete daily PM10 measurements were included, of whom 374 (11.26%) delivered prematurely. Among preterm deliveries, 168 (44.9%) were spontaneous deliveries and 206 (55.1%) were induced. Rank-sum tests showed that, for spontaneous and induced spontaneous deliveries, both mean PM10 concentrations and proportions of intense desert dust episodes were significantly greater among preterm births than among term births. Although the proportion of intense desert dust episodes during pregnancy was significantly associated with spontaneous preterm deliveries, the relation was U-shaped, with an adjusted odds ratio (AOR) = 2 (95%CI = 1.2-3.1) for lowest values relative to median values and AOR = 5.4 (95%CI = 3.2-8.9) for the highest values relative to median values. Similarly, the proportion of intense desert dust episodes during pregnancy was also significantly associated with induced preterm deliveries in a U-shaped manner (AOR = 2.7 (95%CI = 1.6-4.5) for the lowest relative to median values and AOR = 6.8 (95%CI = 3.9-11.9) for the highest relative to median values). Although in our study the relation between PM10 concentrations appeared non-linear, the highest mean concentrations and intense desert dust episodes were indeed associated with both spontaneous and induced preterm delivery.

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Air pollution is a worldwide environmental problem with an impact on human health. Particulate matter of ten micrometers or less aerodynamic diameter (PM10) as well as its fine fraction (PM2.5) is related to multiple pulmonary diseases. The impact of air pollution in Mexico City, and importantly, particulate matter has been studied and considered as a risk factor for two decades ago. Previous studies have reported the composition of Mexico City particulate matter, as well as the biological effects induced by this material. However, material collected and used in previous studies is a limited resource, and sampling and particle recovery techniques have been improved. In this study, we describe the methods used in our laboratory for Mexico City airborne particulate matter PM10 and PM2.5 sampling, considering the years 2017, 2018 and 2019. We also analyzed the PM10 and PM2.5 samples obtained to determine their composition. Finally, we exposed lung cell line cultures to PM10 and PM2.5 to evaluate the biological effect of the material in terms of cell viability, cell death, inflammatory response, and cytogenetic alterations. Our results showed that PM10 composition includes inorganic, organic and biological compounds, while PM2.5 is a mixture of more enriched organic compounds. PM10 and PM2.5 treatment in lung cells does not significantly impact cell viability/cell death. However, PM10 and PM2.5 increase the secretion levels of IL-6. Moreover, PM10 as well as PM2.5 induce cytogenetic alterations, such as micronuclei, anaphase bridges, trinucleated cells and apoptotic cells in lung cells. Our results update the evidence of the composition and biological effects of Mexico City particulate matter and provide us a reliable basis for future approaches.

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Purpose: To evaluate the association between allergic sensitivity and pollen counts in patients with allergic respiratory disease (ARD) and its relationship with atmospheric pollutants. Methods: From 2012 to 2018, we evaluated the sensitivity by skin prick test in ARD patients. The pollen counts were analyzed according to international guidelines (2014-2018). The pollutant and meteorological data were obtained at the same time from AIRE-CDMX websites. We analyzed the association between allergic sensitivity and pollen counts using the χ2 test and stratified by disease allergic rhinitis (AR) and AR with asthma (ARwA), periods (before/after 2015), and pollination seasons (S1:2014-2015), (S2:2015-2016), (S3:2016-2017), (S4:2017-2018). Likewise, we correlated the pollen counts with the concentrations of pollutants using Pearson's correlation. For all analyses, we used SPSS v.21 software, and a p-value <0.05 was considered significant. Results: A total of 520 patients were enrolled, of whom 67.3% had ARwA and 33.7% had AR (p<0.05). The frequency of patients allergic to at least one pollen was higher compared with patients sensitive to indoor allergens (55.3% vs 44.6%, p<0.001). A total of 46.8% of the patients were only sensitive to trees in comparison to other outdoor allergens (p<0.001). The Fraxinus sp. and the Cupressaceae family allergens were approximately two times more frequent than the other tree allergens in both diseases (p<0.05). These pollens doubled their counts since 2015 (p<0.001), which was associated with increases in sensitivity for Fraxinus sp. and the Cupressaceae family compared to previous years (p<0.001). Regarding pollutants, the most significant correlations were with PM10, NO2, PMCO for Fraxinus sp. pollen concentrations in all seasons (p≤0.02). Conclusion: The high increases in pollen counts of the Fraxinus sp. and Cupressaceae family were associated with increases in the frequency of sensitization to these species, and this phenomenon correlated with increases in PM10, NO2, and PMCO.

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Lab-on-a-Chip (LoC) devices are described as versatile, fast, accurate, and low-cost platforms for the handling, detection, characterization, and analysis of a wide range of suspended particles in water-based environments. However, for gas-based applications, particularly in atmospheric aerosols science, LoC platforms are rarely developed. This review summarizes emerging LoC devices for the classification, measurement, and identification of airborne particles, especially those known as Particulate Matter (PM), which are linked to increased morbidity and mortality levels from cardiovascular and respiratory diseases. For these devices, their operating principles and performance parameters are introduced and compared while highlighting their advantages and disadvantages. Discussing the current applications will allow us to identify challenges and determine future directions for developing more robust LoC devices to monitor and analyze airborne PM.

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In this work, fast sequential determination and chemical speciation analysis of inorganic arsenic and antimony in airborne particulate matter collected in outdoor and indoor environments using slurry sampling and detection by hydride generation atomic absorption spectrometry (HG-AAS) is proposed. A Doehlert design was applied to optimise the hydride generation conditions of As and Sb for fast sequential determination in the same aliquot of particulate matter samples after preparation of the slurry. The limits of quantification (LoQ) obtained for As and Sb were 0.3 and 0.9 ng m-3, respectively. The accuracy of the analytical method was confirmed by analysis of the certified reference material of urban particulate matter (SRM NIST 1648a), presenting concordance with certified values of 92.7±7.7% for As and 91.2±9.5% for Sb. Precision was expressed as relative standard deviation (% RSD, n=3), with our results presenting values better than 3.4% and 4.2% for total inorganic As and Sb, respectively. For all analysed samples, total As concentrations and its inorganic species were below the LoQ of the analytical method (<0.3 ng m-3). However, the averages of total inorganic Sb concentrations in airborne particulate matter, collected as total suspended outdoor particles (TSPoutdoor), inhalable particulate matter (PM10), and total suspended indoor particles (TSPindoor), were 3.1±0.5, 2.4±0.6, and 2.6±0.4 ng m-3, respectively. Trivalent Sb (Sb3+) was the predominant inorganic species in all samples investigated, with mean percentages of 76%, 72%, and 73% in TSPoutdoor, PM10, and TSPindoor, respectively. The presence of Sb and its predominant inorganic form (Sb3+) can be attributed to vehicular traffic close to the sampled urban areas. Therefore, fast sequential determination of As and Sb and their inorganic species in particulate matter samples prepared as slurry by FS-HG-AAS is an efficient, accurate, and precise method and can be successfully applied to routine analysis.

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Samples of soil, iron ore, and airborne particulate matter (size <10 µm) were analyzed with the main goal of investigating the differentiating physicochemical properties of their ferruginous compounds. These data were used to identify whether the sources of airborne particulate matter in the metropolitan area of Belo Horizonte, Minas Gerais, Brazil, are either from natural origin, as, for instance, re-suspension of particles from soil, or due to anthropogenic activities, meaning that it would be originated from the many iron ore minings surrounding the metropolitan area. Numerical simulations were used to model the atmospheric dispersion of the airborne particulate matter emitted by iron mining located at the Iron Quadrangle geodomain, Minas Gerais. Results from these numerical simulations supported identifying the sites with the highest concentrations of airborne particulate matter in the metropolitan area. Samples of these suspended materials were collected at the selected sites by using high-volume air samplers. The physicochemical features of the solid materials were assessed by X-ray fluorescence, X-ray diffraction, magnetometry, and 57Fe Mössbauer spectroscopy. The soil materials were found to be rich in quartz, aluminum, organic matter, and low contents of iron, mainly as low crystalline iron oxides. The samples of the iron ores, on the other hand, contain high concentration of iron, dominantly as relatively pure and crystalline hematite (α-Fe2O3). The samples of the airborne particulate matter are rich in iron, mainly as hematite, but contained also quartz, aluminum, and calcium. Mössbauer spectroscopy was used to evaluate the hyperfine structure of 57Fe of the hematite both from the iron ore and the soil samples. The structural characteristics of the hematite of these particulate materials were further explored. The direct influence of the iron ore mining on the composition of the airborne particulate matter was clearly evidenced based on the trace ability of hematite to its source of emission. Even the atmospheric air on regions relatively far away from the mining activities is also significantly influenced.

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In this work, studies using samples collected in an urban area of Aracaju city, Sergipe State, Northeast, Brazil revealed that soil dust in suspension was the main source of total airborne particulate matter (TAPM), followed by vehicular pollution. The concentration profiles for Cu, Fe, Mn, Ni, V and Ti were established for the collected TAPM samples. The concentrations of SO2 and smoke were also measured all along the 42 sampling days. Through multivariate data analysis of the results a correlation between Fe, Mn, Ni and Ti in the mineral composition of the particles was established, indicating soil dust in suspension as the main source of TAPM. The concentrations of Cu and smoke were found to be related to vehicular traffic, and the second largest source of TAPM. Enrichment factors (EF) were calculated for the studied elements, and only Cu was found to be enriched. The concentrations of the elements in TAPM were evaluated using the geoaccumulation index (Igeo), and Fe, Mn, Ni, V and Ti were found to derive from natural sources, in TAPM. However, approximately 55% of the samples did not presented Cu contamination (Igeo≤0), and the remaining 45% presented Cu concentrations levels that indicated between low to moderate (0

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The in vitro genotoxic effects of organic and water-soluble fractions of airborne particulate matter (PM10) with the cytokinesis blocked micronucleus (MN) test in human alveolar carcinoma cells A549 were investigated. Samples were collected in three different sites of São Paulo State, Brazil, and fifteen soluble metals and the sixteen EPÁs priority polycyclic aromatic hydrocarbons (PAH) were chemically determined. PAHs prevailing were fluoranthene and benzo(ghi)perylene. In the water-soluble extracts, highest concentration of metals was found for zinc, iron, and copper in all places of collection. Although PM10 concentration in all samples was in the range of 33.5-110.1µg/m3, lower than 120µg/m3 (limit established by São Paulo State's legislation for PM10 in 24h), MN results showed that of the 24 samples analyzed, five organic and seven water-soluble extracts presented a significant increase in MN frequency. The frequency of MN correlates with the total PAH concentration of the three sites investigated, and the concentration of PM10 is correlated with the biological effect in two of them. For the water-soluble fraction, all the sites presented a relation between the PM10 concentration and the MN frequency. Again, the genotoxic response showed a correlation with the total concentration of water-soluble metals in two of the three sites. Our results confirm the importance of the soluble fraction of PM10 to the genotoxic effect of airborne PM even at low concentration of water-soluble compounds. Thus, together with chemical analysis, the implementation of the MN protocol for both organic and water-soluble fraction biological monitoring could be used as a strategy in a routine air-quality monitoring program, complementing other usual analyses for air pollution control and protection of populations.

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Biologically formed nanoparticles of the strongly magnetic mineral, magnetite, were first detected in the human brain over 20 y ago [Kirschvink JL, Kobayashi-Kirschvink A, Woodford BJ (1992) Proc Natl Acad Sci USA 89(16):7683-7687]. Magnetite can have potentially large impacts on the brain due to its unique combination of redox activity, surface charge, and strongly magnetic behavior. We used magnetic analyses and electron microscopy to identify the abundant presence in the brain of magnetite nanoparticles that are consistent with high-temperature formation, suggesting, therefore, an external, not internal, source. Comprising a separate nanoparticle population from the euhedral particles ascribed to endogenous sources, these brain magnetites are often found with other transition metal nanoparticles, and they display rounded crystal morphologies and fused surface textures, reflecting crystallization upon cooling from an initially heated, iron-bearing source material. Such high-temperature magnetite nanospheres are ubiquitous and abundant in airborne particulate matter pollution. They arise as combustion-derived, iron-rich particles, often associated with other transition metal particles, which condense and/or oxidize upon airborne release. Those magnetite pollutant particles which are <∼200 nm in diameter can enter the brain directly via the olfactory bulb. Their presence proves that externally sourced iron-bearing nanoparticles, rather than their soluble compounds, can be transported directly into the brain, where they may pose hazard to human health.

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Works of particle number and mass concentration variability have a great importance since they may indicate better the influence of vehicle emissions in an urban region. Moreover, the importance of this work lies in the fact that there are few studies in Brazil, where the fuel used has unique characteristics. Consequently, this paper presents measurements of particle number (size range 0.3-10 µm), particle mass (PM10, PM2.5, PM1), O3 and NOx (NO, NO2), in a site near a major highway at the Metropolitan Area of Porto Alegre, south Brazil. Measurements were carried out during two years: 2012 and 2013. Particle number and mass concentrations were measured using an optical counter with a PM10 analyzer. Results showed that concentrations of N0.3-1 (0.3-1 µm) were the highest, although similar to N1-2.5 (1-2.5 µm). Daily variability of the analyzed pollutants followed the traffic pattern. Moreover, NO2, O3, and particle number were higher during the day, whereas NO, NOx, and particle matter showed higher concentrations during nighttime. Traffic influence was evidenced by the mean concentrations of weekends and weekdays, being higher for the latter. Correlation of particles and gases with meteorological variables, together with the application of PCA confirmed the influence of vehicle exhaust discharges.

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The present paper describes the development of a method for the determination of copper in airborne particulate matter using slurry sampling and chemical vapor generation atomic absorption spectrometry (CVG AAS). Chemometric tools were employed to characterize the influence of several factors on the generation of volatile copper species. First, a two-level full factorial design was performed that included the following chemical variables: hydrochloric acid concentration, tetrahydroborate concentration, sulfanilamide concentration and tetrahydroborate volume, using absorbance as the response. Under the established experimental conditions, the hydrochloric acid concentration had the greatest influence on the generation of volatile copper species. Subsequently, a Box-Behnken design was performed to determine the optimum conditions for these parameters. A second chemometric study employing a two-level full factorial design was performed to evaluate the following physical factors: tetrahydroborate flow rate, flame composition, alcohol volume and sample volume. The results of this study demonstrated that the tetrahydroborate flow rate was critical for the process. The chemometric experiments determined the following experimental conditions for the method: hydrochloric acid concentration, 0.208 M; tetrahydroborate concentration, 4.59%; sulfanilamide concentration, 0.79%; tetrahydroborate volume, 2.50 mL; tetrahydroborate flow rate, 6.50 mL min(-1); alcohol volume, 200 µL; and sample volume, 7.0 mL. Thus, this method, using a slurry volume of 500 µL and a final dilution of 7 mL, allowed for the determination of copper with limits of detection and quantification of 0.30 and 0.99 µg L(-1), respectively. Precisions, expressed as RSD%, of 4.6 and 2.8% were obtained using copper solutions at concentrations of 5.0 and 50.0 µg L(-1), respectively. The accuracy was evaluated by the analysis of a certified reference material of urban particulate matter. The copper concentration obtained was 570±63 mg kg(-1), and the certified value was 610±70 mg kg(-1). This method was applied for the determination of copper in airborne particulate matter samples collected in two Brazilian regions of Bahia State, Brazil. The copper contents found varied from 14.46 to 164.31 ng m(-3).

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Objective Assessing the risk to health by inhaling particles and particle-bound PAH during daily commuting along a high traffic flow route/corridor in Bogotá. Methods A van was equipped with a PAS2000 photo-electric sensor for real-time measurement of particle-bound PAH and a Dust Trakfor monitoring PM10 concentration; it drove along typical commuting routes in the city. Exposure to particles and particle-bound PAH was assessed by using an inhalation intake model. Results A similar trend was observed for both PM10 and PAH concentration, indicating that traffic was the same source for both contaminants. Extreme PM10 and PAH inhalation concentrations were recorded every time direct bus and microbus emissions were measured by the van. Inhalation model results indicated that exposure was significantly greater when using a venues having mixed traffic use (i.e. buses, microbuses, passenger vehicles, motorcycles) compared to using roads where the TransMilenio system (articulated buses) had been implemented. Conclusions The results may support evaluating bus drivers, commuters and bike users' exposure to toxic compounds in the city.(AU)

Objetivo El presente estudio buscó estimar la exposición a material particulado e Hidrocarburos Aromáticos Poli cíclicos (HAP) asociados a partículas durante el desplazamiento diario de la población en una vía de alto flujo vehicular en Bogotá. Método Se instaló un equipo "dust-track" para la medición de partículas y un equipo fotoeléctrico "PAS2000" para la medición de los HAP, ambos en un vehículo tipo van que replicó el desplazamiento diario de personas de la casa al trabajo y viceversa. Con el fin de valorar la exposición personal a estos contaminantes según el tipo de vía se usó un modelo de inhalación. Resultados Se observó una tendencia similar entre la concentración del material particulado menor a 10 micrómetros (PM10) y los HAP, indicando que ambos provienen del tráfico principalmente. El modelo de inhalación mostró que las concentraciones a las que está expuesta una persona son mayores en vías con diferentes tipologías de vehículos (carros, buses y busetas, camiones, motocicletas) que en vías de uso exclusivo público para el sistema TransMilenio. Conclusiones Los resultados de este estudio son útiles en la evaluación de la población a contaminantes tóxicos del aire y pueden ser utilizados para apoyar políticas públicas destinadas al mejoramiento de la calidad del aire.(AU)

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The term air pollution comprises a wide variety of chemical and biological components of the outdoor and indoor atmosphere. Air pollution and its effect on human health is critically reviewed in this article with emphasis in the situation of inhabitants of Chilean cities with critical high levels of atmospheric pollution. Atmospheric contaminants that are hazardous for the human health are breathable particulate matter (PM10;PM2,5 and PM0,1) and gaseous chemicals such as nitrogen dioxide, ozone, sulphur dioxide and carbon monoxide. Indoor air contains a variety of noxious compounds derived from multiple sources, being cigarette smoking, heating and cooking appliances, and biological agents and its sub-products the principal ones. Exposure to air pollutants can increase not only morbidity but also mortality rate as well as increasing the number of hospital admissions for patients with respiratory or cardiovascular symptoms. Air pollution is important in determining the quality of life particularly in infants, ageing persons and patients affected by respiratory and cardiovascular diseases. Health professionals should advocate for a cleaner outdoor and indoor atmosphere through the dissemination of our knowledge about the respiratory and non-respiratory effects of air contamination.

El término contaminación del aire incluye una amplia variedad de componentes químicos y biológicos de la atmósfera intra y extradomiciliaria. Este artículo intenta realizar una revisión crítica de los efectos de la contaminación intra y extradomiciliaria sobre la salud humana, poniendo especial énfasis en la situación de los habitantes de ciudades chilenas con niveles críticamente altos de contaminación atmosférica. Los contaminantes atmosféricos riesgosos para la salud humana son el material particulado inhalable (PM10; PM2,5 y PM0,1) y compuestos químicos gaseosos tales como dióxido de nitrógeno, ozono, dióxido de azufre y monóxido de carbono. El aire intradomiciliario contiene una variedad de compuestos nocivos que derivan de múltiples fuentes. Las más importantes son el humo de cigarrillo, artefactos de calefacción y para cocción de alimentos y los agentes biológicos y sus sub-productos. La exposición a contaminantes del aire no solo puede aumentar la tasa de morbilidad sino la tasa de mortalidad como también puede aumentar el número de ingresos hospitalarios de pacientes con síntomas respiratorios y cardiovasculares. La contaminación del aire es importante en la determinación de la calidad de vida de niños menores, ancianos y en pacientes con enfermedades respiratorias y cardiovasculares. Los profesionales de la salud deberían abogar por una atmósfera intra y extradomiciliaria más limpia a través de la difusión del conocimiento que disponemos sobre los efectos respiratorios y no respiratorios de la contaminación del aire.

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