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1.
Environ Sci Pollut Res Int ; 30(40): 91853-91873, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37480530

RESUMO

The objective of the study is to extend the existing literature by investigating the effects of foreign direct investment, gross domestic products and per capita and energy diversification on the nitrogen oxide emissions in Brazil, Russia, India, China and South Africa (BRICS) by using annual data during the period 1992-2019. As per our knowledge, the present study is a first of its kind to examine the impact of a new energy diversification index, based on Herfindahl-Hirschman framework on pollution. This study has adopted a new quantile regression augmented method of moments, which is capable of producing the total impacts of the independent variables across the entire distribution of nitrogen oxides emissions. The findings suggest that an increase in foreign direct investment leads to a decrease in nitrogen oxides emissions at the aggregate level and in both manufacturing and service sectors. We observe that foreign direct investment leads to an increase in nitrogen oxides emissions in the agricultural sector in most of the quantiles. Diversification towards renewable energy causes a decrease in nitrogen oxides emissions in most quantiles at aggregate level, agricultural and manufacturing sectors, whilst diversification leads to an increase in nitrogen oxides emissions in the service sector. The findings also suggest that GDP per capita leads to an increase in NOx emissions in all the quantiles. The study suggests the policy to use and attract more clean energy through foreign direct investment for towards the achievement of sustainable development.


Assuntos
Agricultura , Energia Renovável , Brasil , China , Combustíveis Fósseis
3.
Bull Environ Contam Toxicol ; 104(4): 438-443, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32062695

RESUMO

In the city of Rio de Janeiro (Brazil), the districts located in the northern area are considered the most critical regarding ozone levels year-round. In this study, the potential factors that contribute to high levels of ozone in the district of Irajá were investigated. The obtained results clearly showed that, in spite of the high correlation of ozone concentrations with wind speed and temperature, ozone episodes depend on the ratios of volatile organic compounds (VOCs) to nitrogen oxides (NOx) rather than on the individual VOC and NOx levels, as expected for the VOC-controlled condition typical of the urban area of Rio de Janeiro. Moreover, high VOCs/NOx ratios are highly dependent on the transport of air masses. When pollutants are transported from urban areas with heavy vehicular flux and high NOx concentrations, ozone levels are reduced. When air masses are transported from the industrial petrochemical area, NOx levels are relatively low, and ozone episodes are frequent.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Óxidos de Nitrogênio/análise , Indústria de Petróleo e Gás , Ozônio/análise , Compostos Orgânicos Voláteis/análise , Brasil , Cidades , Vento
4.
Environ Sci Pollut Res Int ; 25(4): 3840-3848, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29178001

RESUMO

The emission profile of volatile organic compounds (VOCs) and nitric oxide (NO) in young and mature leaves of Croton floribundus was assessed in plants exposed to filtered air (FA) and ozone-enriched filtered air (FA+O3). After the period of exposure, leaves were enclosed in polyethylene terephthalate bags and VOCs were collected in young and mature leaves. Both young and mature leaves constitutively emitted the same VOC, but the concentrations were higher in young leaves. O3 exposure induced the emission of sesquiterpenes (mainly ß-caryophyllene) known as antioxidant compounds that may scavenge O3. Young leaves were the highest emitters of sesquiterpenes. O3 induced a rapid accumulation of NO in different tissues and leaf developmental stages; this accumulation was marked in palisade and spongy parenchyma cells in young and mature leaves, respectively. O3 altered the levels of the signaling compound methyl salicylate (MeSA). Moreover, our data showed that NO together with VOC emissions, such as geranyl acetate, α-cadiene, trans-farnesol, cis-ß-farnesene, and MeSA, participate of plant defense mechanisms against the oxidative damage caused by O3.


Assuntos
Poluentes Atmosféricos/toxicidade , Croton/química , Óxido Nítrico/análise , Ozônio/toxicidade , Folhas de Planta/química , Compostos Orgânicos Voláteis/análise , Brasil , Croton/efeitos dos fármacos , Croton/crescimento & desenvolvimento , Modelos Teóricos , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Clima Tropical
5.
Environ Technol ; 37(17): 2133-48, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26776458

RESUMO

Speciation and the influence on the ozone formation potential (OFP) from volatile organic compounds (VOCs) have been studied between February June 2013 in Vitória, ES, Brazil. Passive samplers were installed at three air-quality monitoring stations and a total of 96 samplings were collected. A total of 78 VOCs were characterized by gas chromatograph-mass spectrometer. The predominant group was organic acids, followed by alcohols and substituted aromatics and 14 precursor species were quantified. An analysis correlating concentrations with wind direction was conducted to identify possible sources. The OFP was calculated applying the scale of maximum incremental reactivity proposed by Carter.[ 23 ] Ozone precursors with the greatest OFP such as undecane, toluene, ethylbenzene and m, p-xylene compounds were the most abundant with means of 0.855, 0.365, 0.259 and 0.289 µg m(-3), respectively. The benzene, toluene, ethylbenzene and xylene (BTEX) group was found below the limits considered harmful to the health of the population living in Vitória. The OFP calculated for the precursors group was 22.55 µg m(-3) for the rainy season and 32.11 µg m(-3) for the dry season. The VOC/NOx ratio in Vitória is approximately 1.71, indicating that the region has a VOC-limiting condition for the production of ozone.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Ozônio/química , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/química , Brasil , Cidades , Compostos Orgânicos Voláteis/química
6.
Sci Total Environ ; 543(Pt A): 161-170, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26580739

RESUMO

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.

7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;48(12): 1130-1135, Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762911

RESUMO

Exposure to nitrogen oxides (NOx) emitted by burning fossil fuels has been associated with respiratory diseases. We aimed to estimate the effects of NOx exposure on mortality owing to respiratory diseases in residents of Taubaté, São Paulo, Brazil, of all ages and both sexes. This time-series ecological study from August 1, 2011 to July 31, 2012 used information on deaths caused by respiratory diseases obtained from the Health Department of Taubaté. Estimated daily levels of pollutants (NOx, particulate matter, ozone, carbon monoxide) were obtained from the Centro de Previsão de Tempo e Estudos Climáticos Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System. These environmental variables were used to adjust the multipollutant model for apparent temperature. To estimate association between hospitalizations owing to asthma and air pollutants, generalized additive Poisson regression models were developed, with lags as much as 5 days. There were 385 deaths with a daily mean (±SD) of 1.05±1.03 (range: 0-5). Exposure to NOx was significantly associated with mortality owing to respiratory diseases: relative risk (RR)=1.035 (95% confidence interval [CI]: 1.008-1.063) for lag 2, RR=1.064 (95%CI: 1.017-1.112) lag 3, RR=1.055 (95%CI: 1.025-1.085) lag 4, and RR=1.042 (95%CI: 1.010-1.076) lag 5. A 3 µg/m3 reduction in NOx concentration resulted in a decrease of 10-18 percentage points in risk of death caused by respiratory diseases. Even at NOx concentrations below the acceptable standard, there is association with deaths caused by respiratory diseases.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Óxido Nítrico/toxicidade , Transtornos Respiratórios/etiologia , Transtornos Respiratórios/mortalidade , Poluição do Ar/análise , Brasil/epidemiologia , Monóxido de Carbono/toxicidade , Ozônio/toxicidade , Distribuição de Poisson , Material Particulado/toxicidade , Risco , Sensação Térmica
8.
Br J Pharmacol ; 169(7): 1417-29, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23617570

RESUMO

Biological nitrogen oxide signalling and stress is an area of extreme clinical, pharmacological, toxicological, biochemical and chemical research interest. The utility of nitric oxide and derived species as signalling agents is due to their novel and vast chemical interactions with a variety of biological targets. Herein, the chemistry associated with the interaction of the biologically relevant nitrogen oxide species with fundamental biochemical targets is discussed. Specifically, the chemical interactions of nitrogen oxides with nucleophiles (e.g. thiols), metals (e.g. hemeproteins) and paramagnetic species (e.g. dioxygen and superoxide) are addressed. Importantly, the terms associated with the mechanisms by which NO (and derived species) react with their respective biological targets have been defined by numerous past chemical studies. Thus, in order to assist researchers in referring to chemical processes associated with nitrogen oxide biology, the vernacular associated with these chemical interactions is addressed.


Assuntos
Óxido Nítrico/química , S-Nitrosotióis/química , S-Nitrosotióis/metabolismo , Transdução de Sinais , Animais , Hemeproteínas/química , Metaloproteínas/química , Metais/metabolismo , Nitrosação , Espécies Reativas de Nitrogênio/química , Espécies Reativas de Nitrogênio/metabolismo
9.
Environ Pollut ; 183: 159-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23246369

RESUMO

In this work, a recently developed urban-scale atmospheric dispersion model (DAUMOD-GRS) is applied to evaluate the ground-level ozone (O3) concentrations resulting from anthropogenic area sources of NOx and VOC in the Metropolitan Area of Buenos Aires (MABA). The statistical comparison of model results with observations (including new available data from seventeen sites) shows a good model performance. Estimated summer highest diurnal O3 1-h concentrations in the MABA vary between 15 ppb in the most urbanised area and 53 ppb in the suburbs. All values are below the air quality standard. Several runs are performed to evaluate the impact of possible future emission reductions on O3 concentrations. Under all hypothetical scenarios, the maximum diurnal O3 1-h concentration obtained for the area is slightly reduced (up to 4%). However, maximum diurnal O3 concentrations could increase at some less urbanised areas of MABA depending on the relative reductions of the emissions of NOx and VOC.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Modelos Químicos , Ozônio/análise , Poluentes Atmosféricos/normas , Argentina , Cidades , Ozônio/normas , Estações do Ano , Análise Espacial
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