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1.
Sci Total Environ ; 946: 174164, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38909798

RESUMO

The global interest in edible insects as sustainable protein sources raises concerns about the bioaccumulation of contaminants, including polycyclic aromatic hydrocarbons (PAHs), to problematic levels. Understanding the accumulation dynamics of PAHs in edible insects is highly relevant due to the widespread sources and toxicological profiles; however, the bioaccumulative potential of PAHs in edible insects is unexplored. This study examined the uptake and elimination dynamics of benzo(a)pyrene (B(a)P), a representative and carcinogenic PAH, in yellow mealworm larvae (YMW, Tenebrio molitor). Larvae were exposed to feeding substrate with varying B(a)P concentrations (0.03, 0.3, and 3 mg kg-1), and uptake (21 days in B(a)P-contaminated substrate) and elimination (21 days in B(a)P-free substrate) kinetics were subsequently assessed. The results showed that YMW can eliminate B(a)P, revealing dose-dependent B(a)P bioaccumulation in these insects. Larvae fed on a substrate with 0.03 mg kg-1 accumulated B(a)P over 21 days, presenting values of 0.049 (Standard deviation - 0.011) mg kg-1 and a kinetic-based (BAFkinetic) of 1.93 g substrate g organism-1, exceeding the EU regulatory limits for food. However, with a B(a)P half-life (DT50) of 4.19 days in the larvae, an EU legislation safety criterion was met after a 13-day depuration period in clean substrate. Larvae exposed to substrates with 0.3 and 3 mg kg-1 showed B(a)P accumulation, with BAFkinetic values of 3.27 and 2.09 g substrate g organism-1, respectively, not meeting the current legal standards for food consumption at the end of the exposure to B(a)P. Although the B(a)P half-life values after 35 days were 4.30 and 10.22 days (DT50s), the larvae retained B(a)P levels exceeding permitted food safety limits. These findings highlight a significant oversight in regulating PAHs in animal feed and the need for comprehensive safety evaluations of PAH hazards in edible insects for improved PAH feeding guidelines.


Assuntos
Benzo(a)pireno , Larva , Tenebrio , Animais , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidade , Larva/efeitos dos fármacos , Toxicocinética , Insetos Comestíveis , Bioacumulação , Contaminação de Alimentos
2.
Environ Pollut ; 342: 123121, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086505

RESUMO

Exposure to atmospheric particulate matter (PM) has been associated with heightened risks of lung cancer, cardiovascular and respiratory diseases. PM exposure also affects the immune system, leading to an increased susceptibility to infections, exacerbating pre-existent inflammatory and allergic lung diseases. Atmospheric PM can primarily impact human health through the generation of reactive oxygen species (ROS) that subsequently induce or exacerbate inflammation. These cytotoxic effects have been related with PM concentration, and its chemical constituents, including metals, solvent extractable organics (e.g., polycyclic aromatic hydrocarbons), and water-soluble ions. Although not receiving much attention, the fine aerosol water-soluble organic matter (WSOM) can account for a substantial portion of the overall fine PM mass and has been shown to present strong oxidative and immunomodulatory effects. Thus, the objective of this review is to provide a comprehensive analysis of the role of the water-soluble fraction of PM, with a specific focus on the contribution of the WSOM component to the cytotoxic properties of atmospheric PM. The chemical properties of the water-soluble PM fraction are briefly discussed, while emphasis is put on how PM size, composition, and temporal variations (e.g., seasonality) can impact the pro-oxidative activity, the modulation of inflammatory response, and the cytotoxicity of the water-soluble PM extracts.


Assuntos
Poluentes Atmosféricos , Humanos , Poluentes Atmosféricos/análise , Água/análise , Aerossóis e Gotículas Respiratórios , Material Particulado/análise , Estresse Oxidativo , Aerossóis/análise , Tamanho da Partícula
3.
Hist. ciênc. saúde-Manguinhos ; 31: e2024013, 2024.
Artigo em Português | LILACS | ID: biblio-1557930

RESUMO

O livro de Garfield transita entre vários campos da história, com contribuições à história da Amazônia, dos povos indígenas, das commodities, da comida e alimentação, do consumo, da ciência, da medicina, do meio ambiente. Seu diálogo com a antropologia é fundamental, denso e profícuo. Maneja fontes variegadas com criatividade e vigor metodológico. Temos nas mãos um trabalho de fôlego. Ao final, somos apresentados aos desafios contemporâneos dos sateré-mawé, sua resiliência e criatividade, numa narrativa disruptiva em relação a estereótipos centenários sobre os indígenas.


Assuntos
Fatores Culturais , Paullinia , Fatores Sociológicos , Povos Indígenas , Brasil
4.
J Chromatogr A ; 1706: 464288, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37573757

RESUMO

Analysis of complex environmental matrices poses an extreme challenge for analytical chemists due to the vast number of known and unknown compounds, with very diverse chemical and physical properties. The need for a holistic characterisation of this complexity has sparked the development of effective tools to unravel the chemical composition of such environmental samples. Multidimensional chromatographic methods, namely comprehensive two-dimensional (2D) gas and liquid chromatography (GC × GC and LC × LC, respectively), coupled to different detection systems have emerged as powerful tools with the capability to address this challenge. While GC × GC has steadily gained popularity in environmental analysis, LC × LC is surprisingly less attractive in this research field. This critical review article explores the potential reasons why LC × LC is not the dominant technique used in environmental analysis as compared to GC × GC, while simultaneously highlighting the quite unique role of LC × LC for the target and untargeted analysis of complex environmental matrices. The possible combinations of stationary phases, the important role of the interfacing valve as the heart of an LC × LC assembly, the existing optimization strategies for improving the separation power in the 2D chromatographic space, and the need for user-friendly mathematical tools for multidimensional data handling are also discussed. Finally, a set of practical measures are suggested to increase the use and secure the success of LC × LC in environmental analysis.


Assuntos
Cromatografia Líquida , Cromatografia Líquida/métodos , Cromatografia Gasosa/métodos
5.
Sci Total Environ ; 900: 165744, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37487894

RESUMO

Source apportionment (SA) for indoor air pollution is challenging due to the multiplicity and high variability of indoor sources, the complex physical and chemical processes that act as primary sources, sinks and sources of precursors that lead to secondary formation, and the interconnection with the outdoor environment. While the major indoor sources have been recognized, there is still a need for understanding the contribution of indoor versus outdoor-generated pollutants penetrating indoors, and how SA is influenced by the complex processes that occur in indoor environments. This paper reviews our current understanding of SA, through reviewing information on the SA techniques used, the targeted pollutants that have been studied to date, and their source apportionment, along with limitations or knowledge gaps in this research field. The majority (78 %) of SA studies to date focused on PM chemical composition/size distribution, with fewer studies covering organic compounds such as ketones, carbonyls and aldehydes. Regarding the SA method used, the majority of studies have used Positive Matrix Factorization (31 %), Principal Component Analysis (26 %) and Chemical Mass Balance (7 %) receptor models. The indoor PM sources identified to date include building materials and furniture emissions, indoor combustion-related sources, cooking-related sources, resuspension, cleaning and consumer products emissions, secondary-generated pollutants indoors and other products and activity-related emissions. The outdoor environment contribution to the measured pollutant indoors varies considerably (<10 %- 90 %) among the studies. Future challenges for this research area include the need for optimization of indoor air quality monitoring and data selection as well as the incorporation of physical and chemical processes in indoor air into source apportionment methodology.

6.
Allergo J Int ; : 1-9, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37359419

RESUMO

Airborne pollen allergens-a relevant component of bioaerosols and, therefore, of airborne particulate matter-are considered an important metric in air quality assessments. Although the measurement of airborne pollen allergen concentrations in outdoor environments (namely, in urban areas) has been recognized as a key environmental health indicator, no such obligation exists for indoor environments (dwellings or occupational settings). However, people spend most of their daily time (80-90%) indoors, where the majority of their exposure to air pollution, including pollen allergens, occurs. Nonetheless, the relative importance of airborne pollen allergen exposure indoors differs from outdoors because of differences in pollen loads, sources, dispersion, and degree of penetration from the outdoor surroundings, as well as the differences in the allergenic pollen profiles. In this brief review, we mined the literature over the last 10 years to summarize what existing measurements reveal about the relevance of airborne allergenic pollen in indoor environments. The research priorities on this topic are presented, highlighting the challenges and the motivations for obtaining pollen data in built environments which are key to understand the extent and mechanisms of human exposure to airborne pollen allergens. Thus, we provide a comprehensive assessment of the relevance of airborne allergenic pollen in indoor environments, highlighting knowledge gaps and research needs related to their health effects.

9.
Environ Sci Technol ; 54(2): 1082-1091, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31710482

RESUMO

The impact of inhalable fine particulate matter (PM2.5, aerodynamic diameter <2.5 µm) on public health is of great concern worldwide. Knowledge on their harmful effects are mainly due to studies carried out with whole air particles, with the contribution of their different fractions remaining largely unknown. Herein, a set of urban PM2.5 samples were collected during daytime and nighttime periods in autumn and spring, aiming to address the seasonal and day-night variability of water-soluble organic matter (WSOM) composition. In vitro analysis of the oxidative and pro-inflammatory potential of WSOM samples was carried out in both acute (24 h) and chronic (3 weeks) exposure setups using Raw264.7 macrophages as cell model. Findings revealed that the structural composition of WSOM samples differs between seasons and in a day-night cycle. Cell exposure resulted in an increase in the transcription of the cytoprotective Hmox1 and pro-inflammatory genes Il1b and Nos2, leading to a moderate pro-inflammatory status. These macrophages showed an impaired capacity to subsequently respond to a strong pro-inflammatory stimulus such as bacterial lipopolysaccharide, which may implicate a compromised capacity to manage harmful pathogens. Further investigation on aerosol WSOM could help to constrain the mechanisms of WSOM-induced respiratory diseases and contribute to PM2.5 regulations.


Assuntos
Poluentes Atmosféricos , Aerossóis , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado , Estações do Ano , Água
10.
Clin Genet ; 96(4): 341-353, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31268554

RESUMO

Limb-girdle muscular dystrophies (LGMD) are a group of genetically heterogeneous disorders characterized by predominantly proximal muscle weakness. We aimed to characterize epidemiological, clinical and molecular data of patients with autosomal recessive LGMD2/LGMD-R in Brazil. A multicenter historical cohort study was performed at 13 centers, in which index cases and their affected relatives' data from consecutive families with genetic or pathological diagnosis of LGMD2/LGMD-R were reviewed from July 2017 to August 2018. Survival curves to major handicap for LGMD2A/LGMD-R1-calpain3-related, LGMD2B/LGMD-R2-dysferlin-related and sarcoglycanopathies were built and progressions according to sex and genotype were estimated. In 370 patients (305 families) with LGMD2/LGMD-R, most frequent subtypes were LGMD2A/LGMD-R1-calpain3-related and LGMD2B/LGMD-R2-dysferlin-related, each representing around 30% of families. Sarcoglycanopathies were the most frequent childhood-onset subtype, representing 21% of families. Five percent of families had LGMD2G/LGMD-R7-telethonin-related, an ultra-rare subtype worldwide. Females with LGMD2B/LGMD-R2-dysferlin-related had less severe progression to handicap than males and LGMD2A/LGMD-R1-calpain3-related patients with truncating variants had earlier disease onset and more severe progression to handicap than patients without truncating variants. We have provided paramount epidemiological data of LGMD2/LGMD-R in Brazil that might help on differential diagnosis, better patient care and guiding future collaborative clinical trials and natural history studies in the field.


Assuntos
Genes Recessivos , Estudos de Associação Genética , Predisposição Genética para Doença , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/genética , Idade de Início , Alelos , Biomarcadores , Brasil , Progressão da Doença , Feminino , Frequência do Gene , Estudos de Associação Genética/métodos , Genótipo , Geografia Médica , Humanos , Masculino , Debilidade Muscular , Distrofia Muscular do Cíngulo dos Membros/epidemiologia , Fenótipo , Fatores Sexuais
11.
Pediatr Infect Dis J ; 38(4): 416-418, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30882736

RESUMO

Although bacterial meningitis is a rare presentation of a congenital immunodeficiency, invasive meningococcal disease is classically associated with complement deficiencies. We report a patient from a consanguineous kindred presenting with an invasive meningococcal disease caused by serogroup B meningococcus that revealed an underlying C5 deficiency caused by a novel mutation in the C5 gene.


Assuntos
Complemento C5/deficiência , Saúde da Família , Predisposição Genética para Doença , Meningite Meningocócica/genética , Meningite Meningocócica/patologia , Criança , Complemento C5/genética , Feminino , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Neisseria meningitidis Sorogrupo B/isolamento & purificação , Portugal
12.
Environ Sci Technol ; 53(9): 4959-4967, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30920811

RESUMO

The objectives of this research were to quantify the impact of organic matter content, soil pH and moisture content on the dissolution rate and solubility of copper oxide nanoparticles (CuO NPs) in soil, and to develop an empirical model to predict the dissolution kinetics of CuO NPs in soil. CuO NPs were dosed into standard LUFA soils with various moisture content, pH and organic carbon content. Chemical extractions were applied to measure the CuO NP dissolution kinetics. Doubling the reactive organic carbon content in LUFA 2.1 soil increased the solubility of CuO NP 2.7-fold but did not change the dissolution rate constant. Increasing the soil pH from 5.9 to 6.8 in LUFA 2.2 soil decreased the dissolution rate constant from 0.56 mol1/3·kg1/3·s-1 to 0.17 mol1/3·kg1/3·s-1 without changing the solubility of CuO NP in soil. For six soils, the solubility of CuO NP correlated well with soil organic matter content ( R2 = 0.89) independent of soil pH. In contrast, the dissolution rate constant correlated with pH for pH < 6.3 ( R2 = 0.89), independent of soil organic matter content. These relationships predicted the solubility and dissolution rate constants of CuO NP in two test soils (pH 5.0 and pH 7.6). Moisture content showed negligible impact on the dissolution kinetics of CuO NPs. Our study suggests that soil pH and organic matter content affect the dissolution behavior of CuO NP in soil in a predictable manner.


Assuntos
Nanopartículas , Solo , Cobre , Concentração de Íons de Hidrogênio , Solubilidade
13.
Sci Total Environ ; 648: 430-441, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30121042

RESUMO

This study investigates the structural composition and major sources of water-soluble organic matter (WSOM) from PM2.5 collected, in parallel, during summer and winter, in two contrasting suburban sites at Iberian Peninsula Coast: Aveiro (Portugal) and Coruña (Spain). PM10 samples were also collected at Coruña for comparison. Ambient concentrations of PM2.5, total nitrogen (TN), and WSOM were higher in Aveiro than in Coruña, with the highest levels found in winter at both locations. In Coruña, concentrations of PM10, TN, and WSOM were higher than those from PM2.5. Regardless of the season, stable isotopic δ13C and δ15N in PM2.5 suggested important contributions of anthropogenic fresh organic aerosols (OAs) at Aveiro. In Coruña, δ13C and δ15N of PM2.5 and PM10 suggests decreased anthropogenic input during summer. Although excitation-emission fluorescence profiles were similar for all WSOM samples, multi-dimensional nuclear magnetic resonance (NMR) spectroscopy confirmed differences in their structural composition, reflecting differences in aging processes and/or local sources between the two locations. In PM2.5 WSOM in Aveiro, the relative distribution of non-exchangeable proton functional groups was in the order: HC (40-43%) > HCC (31-39%) > HCO (12-15%) > Ar-H (5.0-13%). However, in PM2.5 and PM10 WSOM in Coruña, the relative contribution of HCO groups (24-30% and 23-29%, respectively) equals and/or surpasses that of HCC (25-26% and 25-29%, respectively), being also higher than those of Aveiro. In both locations, the highest aromatic contents were observed during winter due to biomass burning emissions. The structural composition of PM2.5 and PM10 WSOM in Coruña is dominated by oxygenated aliphatic compounds, reflecting the contribution of secondary OAs from biogenic, soil dust, and minor influence of anthropogenic emissions. In contrast, the composition of PM2.5 WSOM in Aveiro appears to be significantly impacted by fresh and secondary anthropogenic OAs. Marine and biomass burning OAs are important contributors, common to both sites.

14.
Plast Reconstr Surg Glob Open ; 6(2): e1635, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29616161

RESUMO

BACKGROUND: Orofacial clefts are among the most common congenital craniofacial malformations and may be associated with other birth defects. However, the proportion and type of additional anomalies vary greatly between studies. This study assessed the prevalence and type of associated congenital malformations in children with orofacial clefts, who attended the largest cleft lip and palate tertiary referral center in Portugal. METHODS: Consecutive children with orofacial clefts who attended at least 1 consultation in our Clefts Unit between 1981 and 2012 were studied. Demographic and clinical data regarding the number and type of associated malformations were retrospectively collected and analyzed. RESULTS: Of the 701 patients studied, 219 (31.2%) had associated congenital malformations. These malformations were more frequent in children with cleft palate (43.4%) than in children with cleft lip and palate (27.5%) or with cleft lip only (19.4%). Within the group with associated anomalies, 73 cases (33.3%) had conditions related with known chromosomal defects, monogenic syndromes or sequences, and 146 cases (66.7%) had multiple congenital anomalies of unknown origin. From those, head and neck malformations were the most common (60.3%), followed by malformations in the cardiovascular (28.3%) and musculoskeletal systems (26%). CONCLUSIONS: The overall prevalence of associated malformations of nearly 1 in 3 children with orofacial clefts stressed the need for a comprehensive evaluation of these patients by a multidisciplinary cleft team. Moreover, one-third of the children had multiple congenital anomalies of known origins. Thus, early routine screening for other malformations and genetic counseling might be valuable for orofacial clefts management.

16.
Molecules ; 23(5)2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29695037

RESUMO

Myrcia bella Cambess., Myrcia fallax (Rich.) DC. and Myrcia guianensis (Aubl.) DC. (Myrtaceae) are trees found in Brazilian Cerrado. They have been widely used in folk medicine for the treatment of gastrointestinal disorders, hemorrhagic and infectious diseases. Few reports have been found in the literature connecting their phenolic composition and biological activities. In this regard, we have profiled the main phenolic constituents of Myrcia spp. leaves extracts by ESI(−)Q-TOF-MS. The main constituents found were ellagic acid (M. bella), galloyl glucose isomers (M. guianensis) and hexahydroxydiphenic (HHDP) acid derivatives (M. fallax). In addition, quercetin and myricetin derivatives were also found in all Myrcia spp. extracts. The most promising antioxidant activity, measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, was found for M. fallax extracts (EC50 8.61 ± 0.22 µg·mL−1), being slightly less active than quercetin and gallic acid (EC50 2.96 ± 0.17 and 2.03 ± 0.02 µg·mL−1, respectively). For in vitro antiproliferative activity, M. guianensis showed good activity against leukemia (K562 TGI = 7.45 µg·mL−1). The best antimicrobial activity was observed for M. bella and M. fallax to Escherichia coli (300 and 250 µg·mL−1, respectively). In conclusion, the activities found are closely related to the phenolic composition of these plants.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Myrtaceae/química , Extratos Vegetais/farmacologia , Anti-Infecciosos/química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Linhagem Celular Tumoral , Sinergismo Farmacológico , Flavonóis/química , Flavonóis/farmacologia , Humanos , Redes e Vias Metabólicas , Testes de Sensibilidade Microbiana , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
17.
Environ Pollut ; 231(Pt 1): 281-290, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28806693

RESUMO

Organic Aerosols (OAs) are typically defined as highly complex matrices whose composition changes in time and space. Focusing on time vector, this work uses two-dimensional nuclear magnetic resonance (2D NMR) techniques to examine the structural features of water-soluble (WSOM) and alkaline-soluble organic matter (ASOM) sequentially extracted from fine atmospheric aerosols collected in an urban setting during cold and warm seasons. This study reveals molecular signatures not previously decoded in NMR-related studies of OAs as meaningful source markers. Although the ASOM is less hydrophilic and structurally diverse than its WSOM counterpart, both fractions feature a core with heteroatom-rich branched aliphatics from both primary (natural and anthropogenic) and secondary origin, aromatic secondary organics originated from anthropogenic aromatic precursors, as well as primary saccharides and amino sugar derivatives from biogenic emissions. These common structures represent those 2D NMR spectral signatures that are present in both seasons and can thus be seen as an "annual background" profile of the structural composition of OAs at the urban location. Lignin-derived structures, nitroaromatics, disaccharides, and anhydrosaccharides signatures were also identified in the WSOM samples only from periods identified as smoke impacted, which reflects the influence of biomass-burning sources. The NMR dataset on the H-C molecules backbone was also used to propose a semi-quantitative structural model of urban WSOM, which will aid efforts for more realistic studies relating the chemical properties of OAs with their atmospheric behavior.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Biomassa , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética/métodos , Material Particulado/análise , Estações do Ano , Fumaça , Água/química
18.
Environ Pollut ; 227: 513-525, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28499261

RESUMO

This study describes and compares the key structural units present in water-soluble organic carbon (WSOC) fraction of atmospheric aerosols collected in different South American (Colombia - Medellín and Bogotá, Peru - Lima, Argentina - Buenos Aires, and Brazil - Rio de Janeiro, São Paulo, and Porto Velho, during moderate (MBB) and intense (IBB) biomass burning) and Western European (Portugal - Aveiro and Lisbon) locations. Proton nuclear magnetic resonance (1H NMR) spectroscopy was employed to assess the relative distribution of non-exchangeable proton functional groups in aerosol WSOC of diverse origin, for the first time to the authors' knowledge in South America. The relative contribution of the proton functional groups was in the order H-C > H-C-C= > H-C-O > Ar-H, except in Porto Velho during MBB, Medellín, Bogotá, and Buenos Aires, for which the relative contribution of H-C-O was higher than that of H-C-C=. The 1H NMR source attribution confirmed differences in aging processes or regional sources between the two geographic regions, allowing the differentiation between urban combustion-related aerosol and biological particles. The aerosol WSOC in Aveiro, Lisbon, and Rio de Janeiro during summer are more oxidized than those from the remaining locations, indicating the predominance of secondary organic aerosols. Fresh emissions, namely of smoke particles, becomes important during winter in Aveiro and São Paulo, and in Porto Velho during IBB. The biosphere is an important source altering the chemical composition of aerosol WSOC in South America locations. The source attribution in Medellín, Bogotá, Buenos Aires, and Lima confirmed the mixed contributions of biological material, secondary formation, as well as urban and biomass burning emissions. Overall, the information and knowledge acquired in this study provide important diagnostic tools for future studies aiming at understanding the water-soluble organic aerosol problem, their sources and impact at a wider geographic scale.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Argentina , Biomassa , Brasil , Europa (Continente) , Espectroscopia de Ressonância Magnética/métodos , Material Particulado/análise , Peru , Portugal , Estações do Ano , América do Sul
19.
Environ Sci Pollut Res Int ; 24(12): 11006-11016, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27726076

RESUMO

In the framework of two national research projects (ORGANOSOL and CN-linkAIR), fine particulate matter (PM2.5) was sampled for 17 months at an urban location in the Western European Coast. The PM2.5 samples were analyzed for organic carbon (OC), water-soluble organic carbon (WSOC), elemental carbon (EC), major water-soluble inorganic ions, mineralogical, and for the first time in this region, strontium isotope (87Sr/86Sr) composition. Organic matter dominates the identifiable urban PM2.5 mass, followed by secondary inorganic aerosols. The acquired data resulted also in a seasonal overview of the carbonaceous and inorganic aerosol composition, with an important contribution from primary biomass burning and secondary formation processes in colder and warmer periods, respectively. The fossil-related primary EC seems to be continually present throughout the sampling period. The 87Sr/86Sr ratios were measured on both the labile and residual PM2.5 fractions as well as on the bulk PM2.5 samples. Regardless of the air mass origin, the residual fractions are more radiogenic (representative of a natural crustal dust source) than the labile fractions, whose 87Sr/86Sr ratios are comparable to that of seawater. The 87Sr/86Sr ratios and the mineralogical composition data further suggest that sea salt and mineral dust are important primary natural sources of fine aerosols throughout the sampling period.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Isótopos de Estrôncio/análise , Carbono/análise , Cidades , Material Particulado , Portugal
20.
Chemosphere ; 145: 215-23, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26688258

RESUMO

The chemical and light-absorption dynamics of organic aerosols (OAs), a master variable in the atmosphere, have yet to be resolved. This study uses a comprehensive multidimensional analysis approach for exploiting simultaneously the compositional changes over a molecular size continuum and associated light-absorption (ultraviolet absorbance and fluorescence) properties of two chemically distinct pools of urban OAs chromophores. Up to 45% of aerosol organic carbon (OC) is soluble in water and consists of a complex mixture of fluorescent and UV-absorbing constituents, with diverse relative abundances, hydrophobic, and molecular weight (Mw) characteristics between warm and cold periods. In contrast, the refractory alkaline-soluble OC pool (up to 18%) is represented along a similar Mw and light-absorption continuum throughout the different seasons. Results suggest that these alkaline-soluble chromophores may actually originate from primary OAs sources in the urban site. This work shows that the comprehensive multidimensional analysis method is a powerful and complementary tool for the characterization of OAs fractions. The great diversity in the chemical composition and optical properties of OAs chromophores, including both water-soluble and alkaline-soluble OC, may be an important contribution to explain the contrasting photo-reactivity and atmospheric behavior of OAs.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Compostos Orgânicos/análise , Aerossóis/química , Poluentes Atmosféricos/química , Cidades , Interações Hidrofóbicas e Hidrofílicas , Luz , Peso Molecular , Compostos Orgânicos/química , Estações do Ano , Água/química
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