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1.
Sci Total Environ ; 692: 1165-1174, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539948

RESUMO

The management system of soils and nitrogen application can cause impacts on the N2O emissions produced by the agricultural sector. In the establishment of practices of greenhouse gas mitigation for this sector, the objective of this study was to evaluate the effect of soil tillage, with and without N fertilization, on N2O emissions from Oxisols under rainfed maize in the Brazilian Cerrado region. The managements were of monoculture maize under conventional tillage (CT) and no-tillage (NT), with (1) and without (0) application of N fertilizer (0 and 257 kg N ha-1). From November 2014 to October 2015, gas emissions were measured. The soil and climate variables were measured and related to the N2O fluxes. In the N-fertilized treatments, N2O fluxes were higher (P < 0.01), ranging from -21 µg m-2 h-1 to 548 µg m-2 h-1 N2O under conventional tillage and from -21 µg m-2 h-1 to 380 µg m-2 h-1 N2O under no-tillage, compared with -6 to 93 µg m-2 h-1 N2O from systems without N application. There was a combined effect of mineral N and water-filled pore space for most N2O fluxes. The emission factors of N2O during maize cultivation were lower than the standard factor (1%) established by the International Panel of Climate Change. During the plant crop cycle, 30% less N2O was emitted from the N-fertilized no-tillage than from the conventional tillage. For the total cumulative N2O (crop cycle + fallow), the N2O emissions from NT1 and CT1 were not different, but 10× higher than those from the respective crops without N fertilization. To the emissions per unit of grain yield, CT1 and NT1 emitted 769 and 391 mg N2O kg-1 grain produced, respectively, and NT1 was most efficient in fertilizer-into-product conversion. Under maize cultivation, the soil acted as N2O source, regardless of the management.


Assuntos
Agricultura/métodos , Poluição do Ar/prevenção & controle , Fertilizantes , Gases de Efeito Estufa/análise , Dióxido de Nitrogênio/análise , Zea mays/crescimento & desenvolvimento , Poluição do Ar/estatística & dados numéricos , Brasil , Solo
2.
Sci Total Environ ; 685: 1075-1086, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390698

RESUMO

Biochar applications have been proposed for mitigating some soil greenhouse gas (GHG) emissions. However, results can range from mitigation to no effects. To explain these differences, mechanisms have been proposed but their reliability depends on biochar type, soil and climatic conditions. Furthermore, it is found that the mitigation capacity is dependent on how the biochar is aging under field conditions. The effects on N2O, CH4 and CO2 emission rates of a gasification pine biochar (applied as 0, 5, and 30 t ha-1) were studied between 8 and 21 months of the application in an alkaline soil cropped to barley under Mediterranean climate. Together with GHG, soil chemical and biological properties were assessed, namely, changes in labile organic matter content and nutrient status, and pH, as well as microbial abundance, activity, and functional composition. During the 2 years of the application, significant changes were observed at the highest rate of biochar application such as higher contents of water, K+, Mg2+, SO42-, higher basal respiration, and with non-significant changes in microbial community, though with some temporal effects. Regarding GHG, N2O decreases coupled with CH4 increases in the summer sampling were measured, although only for the highest application rate scenario. Such effects were unrelated to pH, bioavailable nitrogen status, or bulk soil microbial community shifts. We hypothesized that the key is the porous structure of our wood biochar, which is able to provide more and diversified microbial microhabitats in comparison to bulk soil. At higher temperatures in summer, biologically-induced anoxic conditions in biochar pores acting as microsites may be promoted, where total denitrification to N2 occurs which leads to N2O uptake, while CH4 production is promoted.


Assuntos
Carvão Vegetal , Metano/análise , Dióxido de Nitrogênio/análise , Temperatura Ambiente , Agricultura , Ecossistema , Região do Mediterrâneo
3.
Environ Monit Assess ; 191(8): 484, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31280377

RESUMO

Epidemiological research requires accurate prediction of the concentrations of air pollutants. In this study, satellite-based estimates (OMI NO2), distance-weighted models (DWMs), and universal kriging (UK) are applied to land use regression (LUR) to predict annually and monthly averaged NO2 concentrations in the continental United States. In addition, to assess environmental risk, the relationship between NO2 concentrations and people potentially exposed to NO2 within urban areas is explored in 377 metropolitan statistical areas (MSAs). The results of this study show that the application of a combination of OMI NO2, UK, and DWMs to LUR yielded the highest cross-validated (CV) R2 values and the lowest root mean square error of prediction (RMSEP): 82.9% and 0.392 on a square root scale of ppb in the annual model and 70.4-83.5% and 0.408-0.518 on square root scale of ppb in the monthly models, respectively. Moreover, the model presented a spatially unbiased distribution of CV error terms. Models based on LUR provided more accurate NO2 predictions with lower RMSEP in urban areas than in rural areas. In addition, this study finds that the people living in the urban areas of MSAs, with larger populations and a higher percentage of children under 18 years of age, are likely to be exposed to higher NO2 concentrations. By contrast, people living in the urban areas of MSAs with a higher percentage of the elderly over 65 years of age are likely to be exposed to lower NO2 concentrations.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Dióxido de Nitrogênio/análise , Adolescente , Idoso , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Criança , Pré-Escolar , Monitoramento Ambiental/métodos , Humanos , Análise Espacial , Estados Unidos
4.
Environ Pollut ; 252(Pt B): 1235-1245, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252121

RESUMO

Previous meta-analyses on associations between air pollution (AP) and type 2 diabetes mellitus (T2DM) were mainly focused on studies conducted in high-income countries. Evidence should be updated by including more recent studies, especially those conducted in low- and middle-income countries. We therefore conducted a systematic review and meta-analysis of epidemiological studies to conclude an updated pooled effect estimates between long-term AP exposure and the prevalence and incidence of T2DM. We searched PubMed, Embase, and Web of Science to identify studies regarding associations of AP with T2DM prevalence and incidence prior to January 2019. A random-effects model was employed to analyze the overall effects. A total of 30 articles were finally included in this meta-analysis. The pooled results showed that higher levels of AP exposure were significantly associated with higher prevalence of T2DM (per 10 µg/m3 increase in concentrations of particles with aerodynamic diameter < 2.5 µm (PM2.5): odds ratio (OR) = 1.09, 95% confidence interval (95%CI): 1.05, 1.13; particles with aerodynamic diameter < 10 µm (PM10): OR = 1.12, 95%CI: 1.06, 1.19; nitrogen dioxide (NO2): OR = 1.05, 95%CI:1.03, 1.08). Besides, higher level of PM2.5 exposure was associated with higher T2DM incidence (per 10 µg/m3 increase in concentration of PM2.5: hazard ratio (HR) = 1.10, 95%CI:1.04, 1.16), while the associations between PM10, NO2 and T2DM incidence were not statistically significant. The associations between AP exposure and T2DM prevalence showed no significant difference between high-income countries and low- and middle-incomes countries. However, different associations were identified between PM2.5 exposure and T2DM prevalence in different geographic areas. No significant differences were found in associations of AP and T2DM prevalence/incidence between females and males, except for the effect of NO2 on T2DM incidence. Overall, AP exposure was positively associated with T2DM. There still remains a need for evidence from low- and middle-income countries on the relationships between AP and T2DM.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Diabetes Mellitus Tipo 2/epidemiologia , Exposição Ambiental/análise , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Diabetes Mellitus Tipo 2/induzido quimicamente , Feminino , Humanos , Incidência , Masculino , Dióxido de Nitrogênio/análise , Razão de Chances , Material Particulado/toxicidade , Prevalência
5.
Water Sci Technol ; 79(8): 1616-1625, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31169520

RESUMO

To be able to fulfill the Paris agreement regarding anthropogenic greenhouse gases, all potential emissions must be mitigated. Wastewater treatment plants should aim to eliminate emissions of the most potent greenhouse gas, nitrous oxide (N2O). In this study, these emissions were measured at a full-scale reject water treatment tank during two different operation modes: nitrification/denitrification (N/DN) operating as a sequencing batch reactor (SBR), and deammonification (nitritation/anammox) as a moving bed biofilm reactor (MBBR). The treatment process emitted significantly less nitrous oxide in deammonification mode 0.14-0.7%, compared to 10% of total nitrogen in N/DN mode. The decrease can be linked to the changed feeding strategy, the lower concentrations of nitrite, a lower load of ammonia oxidized, a shorter aeration time, the absence of non-optimized ethanol dosage or periodic lack of oxygen as well as the introduction of biofilm. Further, evaluation was done how the operational pH set point influenced the emissions in deammonification mode. Lower concentrations of nitrous oxide were measured in water phase at higher pH (7.5-7.6) than at lower pH (6.6-7.1). This is believed to be mainly because of the lower aeration ratio and increased complete denitrification at the higher pH set point.


Assuntos
Reatores Biológicos , Desnitrificação , Nitrificação , Dióxido de Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos , Biofilmes , Concentração de Íons de Hidrogênio , Óxido Nitroso , Paris , Águas Residuárias , Água
6.
Environ Sci Pollut Res Int ; 26(23): 23524-23541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203549

RESUMO

The densely populated Greater Cairo (GC) region suffers from severe air quality issues caused by high levels of anthropogenic activities, such as motorized traffic, industries, and agricultural biomass burning events, along with natural sources of particulate matter, such as wind erosion of arid surfaces. Surface-measured concentrations of particulate matter (PM10), sulfur dioxide (SO2), and ozone (O3) and its precursor's gases (nitrogen dioxide, NO2; carbon monoxide, CO) were obtained for the GC region. The PM10 concentrations were found to exceed remarkably the Egyptian guidelines (150 µg/m3). These high levels of PM10 were recorded throughout 68% of the period of measurement in some industrial areas (El-Kolaly). The measured data of pollutants were used for both the evaluation of environmental pollution levels and the validation of the online-integrated regional climate chemistry model "RegCM-CHEM4." Calculation of the bias between the model results and the measured data was used to evaluate the model performance in order to assess its ability in reproducing the chemical species over the area. The model was found to reproduce the seasonal cycle of the pollutants successfully, but with a large underestimation of the PM10 values. Validation of the RegCM-CHEM4 indicated that the emission inventories of mobile sources and anthropogenic activities need to be improved especially with respect to local and regional activities in order to enhance air quality simulations over the GC region.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Modelos Químicos , Poluição do Ar/análise , Monóxido de Carbono/análise , Cidades , Egito , Indústrias , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Dióxido de Enxofre/análise , Vento
7.
Environ Monit Assess ; 191(7): 470, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31250261

RESUMO

Particulate and gaseous emissions from intensive poultry facilities are major public and environmental health concern. The present study was aimed at exploratively monitoring particulate matter (PM) and gaseous concentrations in controlled-environment facilities using low-cost sensors in Lahore, Pakistan. The indoors and outdoors of 18 broiler houses, grouped into three categories based on the age of birds: group I (1-20 days), group II (21-30 days) and group III (31-40 days), were examined. Low-cost sensors Dylos 1700 and Aeroqual 500 series with different gas sensor heads were used to monitor PM and different gases such as nitrogen dioxide (NO2), hydrogen sulphide (H2S), carbon dioxide (CO2) and methane (CH4), respectively. Overall, the mean PM and gaseous concentrations increased with the age and activity of birds as compared with the non-activity time of birds. Statistically significant differences were observed in all measured parameters among the groups. The negative correlation between indoor and outdoor environments for PM and gas concentrations at some broiler houses demonstrates the contribution of additional sources to emissions in outdoor environments. The findings contribute to our knowledge of temporal characteristics of particulate and gaseous concentrations from poultry facilities particularly in Pakistan and generally to the capability of using low-cost sensors to evaluate emissions from such facilities.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Gases/análise , Material Particulado/análise , Animais , Dióxido de Carbono/análise , Galinhas , Poeira/análise , Sulfeto de Hidrogênio/análise , Metano/análise , Dióxido de Nitrogênio/análise , Paquistão , Aves Domésticas
8.
Environ Pollut ; 251: 885-891, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31234254

RESUMO

Guangdong Province, which is located in southern China, has a tropical climate with high temperatures and humidity, making it extremely unfavourable for the corrosion resistance of various materials. Meanwhile, as a quickly developing region in China, Guangdong Province is also facing multi-pollutant conditions, which seriously affect the atmospheric degradation of the materials in this region. It is therefore necessary to identify the key air pollutants that affect the atmospheric corrosivity of Guangdong Province and to propose targets of air pollutant control. An analysis of the environmental data and corrosion rates in Guangdong Province showed that the atmospheric corrosivity of the entire region is closely related to the presence of sulfur dioxide (SO2) and ozone (O3). In addition, a superposition model was utilised to reflect the synergistic effect of SO2 and O3, and a superimposed map of both pollutants was drawn to demonstrate their amount. To control the corrosion rate of carbon steel and avoid exceeding the C2 classification in ISO 9223, the following targets of air pollutant control are proposed: an SO2 concentration of lower than 10 µg m-3 and an O3 level of lower than 85 µg m-3.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Ozônio/análise , Dióxido de Enxofre/análise , China , Corrosão , Temperatura Alta , Umidade , Dióxido de Nitrogênio/análise , Material Particulado/análise
10.
JAMA ; 321(19): 1906-1915, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31112259

RESUMO

Importance: Exposure to air pollutants is a well-established cause of asthma exacerbation in children; whether air pollutants play a role in the development of childhood asthma, however, remains uncertain. Objective: To examine whether decreasing regional air pollutants were associated with reduced incidence of childhood asthma. Design, Setting, and Participants: A multilevel longitudinal cohort drawn from 3 waves of the Southern California Children's Health Study over a period of air pollution decline. Each cohort was followed up from 4th to 12th grade (8 years): 1993-2001, 1996-2004, and 2006-2014. Final follow-up for these data was June 2014. Population-based recruitment was from public elementary schools. A total of 4140 children with no history of asthma and residing in 1 of 9 Children's Health Study communities at baseline were included. Exposures: Annual mean community-level ozone, nitrogen dioxide, and particulate matter less than 10 µm (PM10) and less than 2.5 µm (PM2.5) in the baseline year for each of 3 cohorts. Main Outcomes and Measures: Prospectively identified incident asthma, collected via questionnaires during follow-up. Results: Among the 4140 children included in this study (mean [SD] age at baseline, 9.5 [0.6] years; 52.6% female [n = 2 179]; 58.6% white [n = 2273]; and 42.2% Hispanic [n = 1686]), 525 incident asthma cases were identified. For nitrogen dioxide, the incidence rate ratio (IRR) for asthma was 0.80 (95% CI, 0.71-0.90) for a median reduction of 4.3 parts per billion, with an absolute incidence rate decrease of 0.83 cases per 100 person-years. For PM2.5, the IRR was 0.81 (95% CI, 0.67-0.98) for a median reduction of 8.1 µg/m3, with an absolute incidence rate decrease of 1.53 cases per 100 person-years. For ozone, the IRR for asthma was 0.85 (95% CI, 0.71-1.02) for a median reduction of 8.9 parts per billion, with an absolute incidence rate decrease of 0.78 cases per 100 person-years. For PM10, the IRR was 0.93 (95% CI, 0.82-1.07) for a median reduction of 4.0 µg/m3, with an absolute incidence rate decrease of 0.46 cases per 100 person-years. Conclusions and Relevance: Among children in Southern California, decreases in ambient nitrogen dioxide and PM2.5 between 1993 and 2014 were significantly associated with lower asthma incidence. There were no statistically significant associations for ozone or PM10.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Asma/epidemiologia , Dióxido de Nitrogênio/efeitos adversos , Material Particulado/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Asma/etiologia , California/epidemiologia , Criança , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Dióxido de Nitrogênio/análise , Ozônio/efeitos adversos , Ozônio/análise , Material Particulado/análise
11.
Artigo em Inglês | MEDLINE | ID: mdl-31060269

RESUMO

Spatial saturation studies using source-specific chemical tracers are commonly used to examine intra-urban variation in exposures and source impacts, for epidemiology and policy purposes. Most such studies, however, has been performed in North America and Europe, with substantial regional combustion-source contributions. In contrast, Auckland, New Zealand, a large western city, is relatively isolated in the south Pacific, with minimal impact from long-range combustion sources. However, fluctuating wind patterns, complex terrain, and an adjacent major port complicate pollution patterns within the central business district (CBD). We monitored multiple pollutants (fine particulate matter (PM2.5), black carbon (BC), elemental composition, organic diesel tracers (polycyclic aromatic hydrocarbons (PAHs), hopanes, steranes), and nitrogen dioxide (NO2)) at 12 sites across the ~5 km2 CBD during autumn 2014, to capture spatial variation in traffic, diesel, and proximity to the port. PM2.5 concentrations varied 2.5-fold and NO2 concentrations 2.9-fold across the CBD, though constituents varied more dramatically. The highest-concentration constituent was sodium (Na), a distinct non-combustion-related tracer for sea salt (µ = 197.8 ng/m3 (SD = 163.1 ng/m3)). BC, often used as a diesel-emissions tracer, varied more than five-fold across sites. Vanadium (V), higher near the ports, varied more than 40-fold across sites. Concentrations of most combustion-related constituents were higher near heavy traffic, truck, or bus activity, and near the port. Wind speed modified absolute concentrations, and wind direction modified spatial patterns in concentrations (i.e., ports impacts were more notable with winds from the northeast).


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Emissões de Veículos/análise , Cidades , Nova Zelândia , Dióxido de Nitrogênio/análise , Estações do Ano , Fuligem/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-31035528

RESUMO

China's rapid urbanization and industrialization have affected the spatiotemporal patterns of nitrogen dioxide (NO2) pollution, which has led to greater environmental pressures. In order to mitigate the environmental pressures caused by NO2 pollution, it is of vital importance to investigate the influencing factors. We first obtained data for NO2 pollution at the city level using satellite observation techniques and analyzed its spatial distribution. Next, we introduced a theoretical framework, an extended stochastic impacts by regression on population, affluence, and technology (STIRPAT) model, to quantify the relationship between NO2 pollution and its contributing natural and socio-economic factors. The results are as follows. Cities with high NO2 pollution are mainly concentrated in the North China Plain. On the contrary, southwestern cities are characterized by low NO2 pollution. In addition, we find that population, per capita gross domestic product, the share of the secondary industry, ambient air pressures, total nighttime light data, and urban road area have a positive impact on NO2 pollution. In contrast, increases in the normalized difference vegetation index (NDVI), relative humidity, temperature, and wind speed may reduce NO2 pollution. These empirical results should help the government to effectively and efficiently implement further emission reductions and energy saving policies in Chinese cities in a bid to mitigate the environmental pressures.


Assuntos
Poluentes Atmosféricos/análise , Modelos Teóricos , Dióxido de Nitrogênio/análise , Poluição do Ar , China , Cidades , Comunicações Via Satélite , Urbanização , Tempo (Meteorologia)
13.
BMC Public Health ; 19(1): 620, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117980

RESUMO

BACKGROUND: There has been growing global concern about air pollution due to its great risk to public health. In Japan, although industrial- and traffic-related air pollution has been decreasing, concerns about particulate matter air pollution has been growing in recent years. In this study, we examined the effects of air pollution on symptoms and the health status of healthy subjects in Japan. METHODS: Participants (n = 2887) who visited healthcare centers in Kumamoto or Niigata prefectures in February from 2010 to 2015 were asked to fill out a questionnaire, which was a self-completed booklet containing questions on the characteristics of participants, their respiratory symptoms, and questionnaires on their health status in February, May, and July. Generalized estimating equation analyses were performed to predict the factors associated with the symptoms and health status using two-week averages of air quality parameters obtained from 49 monitoring stations as independent variables. RESULTS: Only allergy was associated with air quality in both areas. Prevalence of the other respiratory symptoms were correlated with air quality only in Kumamoto. The health statuses including the 'physical fitness', 'daily activities', and 'social activities' domains were related only to time spent outdoors. The 'overall health' was associated with time spent outdoors and concentrations of nitrogen dioxide and suspended particulate matters (SPM) in Kumamoto, and with temperatures and SPM in Niigata. The 'pain' score was correlated with temperature and carbon monoxide concentration only in Kumamoto. In Kumamoto, the 'quality of life (QoL)' was worse in those who spent shorter hours outdoors, were exposed to lower humidity, higher concentrations of oxidants, SPM, and PM2.5, and who experienced more Asian sand dust (ASD) events. In Niigata, a worsened 'QoL' was associated with time spent outdoors, temperature, and SPM. CONCLUSIONS: The associations between air quality and the health status was found mainly in the comprehensive domain of the health status such as 'overall health' and 'QoL'. The effect of short-term exposure to larger particles, such as SPM, on health status was observed when compared to smaller particles such as PM2.5 and gaseous pollutants.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Autoavaliação Diagnóstica , Exposição Ambiental/estatística & dados numéricos , Adulto , Monóxido de Carbono/análise , Poeira/análise , Feminino , Nível de Saúde , Humanos , Umidade , Hipersensibilidade/epidemiologia , Japão/epidemiologia , Masculino , Dióxido de Nitrogênio/análise , Material Particulado/análise , Qualidade de Vida , Doenças Respiratórias/epidemiologia , Inquéritos e Questionários , Temperatura Ambiente , Fatores de Tempo
14.
Ecotoxicol Environ Saf ; 180: 542-548, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31128552

RESUMO

The primary objective of the present study was to evaluate the concentrations and short and long-term excess mortality attributed to PM2.5, NO2, and O3 observed in ambient air of Ahvaz during March 2014 to March 2017 period using the AirQ + software developed by the World Health Organization (WHO), which is updated in 2016 by WHO European Centre for Environment and Health. The hourly concentrations of PM2.5, O3, and NO2 measured at different regulatory monitoring network stations in Ahvaz city were obtained from the Department of Environment (DOE) of the city. Then, for various air quality monitoring stations, the 24-h average concentration of PM2.5, 1-h average of NO2 concentration, and maximum daily 8-h O3 concentrations were calculated using Excel 2010 software. When the maximum daily 8-h ozone means exceeding the value of 35, it was subtracted from 35 to calculate SOMO35 indicator for modeling. Validation of air quality data was performed according to the Aphekom and WHO's methodologies for health impact assessment of air pollution. Year-specific city population and baseline incidence of the health outcomes were obtained. The three-year averages of PM2.5, NO2, and O3 concentrations were 68.95 (±39.86) µg/m3, 135.90 (±47.82) µg/m3, and 38.63 (±12.83) parts-per-billion-volume (ppbv), respectively. SOMO35 values of ozone were 6596.66, 3411.78, and 470.88 ppbv in 2014-2015, 2015-2016, and 2016-2017 years, respectively. The AP and number of natural deaths due to NO2 were higher than PM2.5 except the last year (2016-2017), causing about 39.18%, 40.73%, and 14.39% of deaths within the first, the second, and the third year, respectively. However, for the last year, the natural mortality for PM2.5 was higher than NO2 (34.46% versus 14.39%). The total number of natural mortality caused by PM2.5 and NO2 in all years was 4061 and 4391, respectively. A significant number of deaths was estimated to be attributed to the given air pollutants. It can be concluded that by designing and implementing air pollution control strategies and actions, both health effects and economic losses will be prevented.


Assuntos
Poluentes Atmosféricos/toxicidade , Dióxido de Nitrogênio/toxicidade , Ozônio/toxicidade , Material Particulado/toxicidade , Adulto , Poluentes Atmosféricos/análise , Pré-Escolar , Cidades , Exposição Ambiental , Avaliação do Impacto na Saúde , Humanos , Irã (Geográfico) , Mortalidade , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise
15.
Environ Int ; 127: 317-323, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30953814

RESUMO

RATIONALE: A link is established between air pollution and respiratory diseases. Very few studies evaluated this link with primary spontaneous pneumothorax (PSP). Contrasted results, low statistical power and methodological limits of these studies brought us to evaluate in a more thorough way this link. OBJECTIVES: (1) to estimate the relation between PSP and air pollutants namely nitrogen dioxide (NO2), ozone (O3) and particulate matter with a diameter ≤ 10 µm (PM10); (2) to investigate a time lag effect between these pollutants and occurrence of PSP. METHODS: This study has a case-crossover design. Subjects aged ≥18 years admitted from 1st June 2009 to 31st May 2013, in 14 Emergency Departments centers on the French territory. Were excluded: patients with traumatic, secondary, recurrent or history of previous pneumothorax. NO2, O3 and PM10 data were collected hourly in monitoring stations. Three exposure assessments were retained: quantitative values, fast increase concentration of air pollutants and peak of pollution. These assessments were calculated for the entire exposure period and for each of the four days of all case and control periods. RESULTS: 948 subjects included. Whatever the pollutant considered, no differences were observed between case and control periods, regardless of whether the quantitative values of air pollutants exposure (p > 0.09), fast increase concentration (p > 0.46) and peak of pollution (p > 0.20). CONCLUSIONS: We failed to show a relation between PSP and short-term air pollution exposure to low levels of NO2 and PM10. An association between O3 exposure and PSP cannot be ruled out. An impact at higher exposure level, and/or a potentiating effect of different meteorological factors remain to be demonstrated.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Pneumotórax/induzido quimicamente , Adulto , Poluição do Ar/análise , Estudos Cross-Over , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/análise , Ozônio/análise
16.
J Environ Sci (China) ; 80: 186-196, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30952336

RESUMO

Ground-basedMulti-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements were performed at Shangdianzi (SDZ) regional atmospheric background station in northern China from March 2009 to February 2011. The tropospheric NO2 vertical column densities (VCDs) were retrieved to investigate the background condition of the Beijing-Tianjin-Hebei developed economic circle in China. The seasonal variation of mean NO2 tropospheric VCDs (VCDTrop) at SDZ is apparent, with the maximum (1.3 × 1016 molec/cm2) in February and the minimum (3.5 × 1015 molec/cm2) in August, much lower than those observed at the Beijing city center. The average daytime diurnal variations of NO2 VCDTrop are rather consistent for all four seasons, presenting the minimum at noon and the higher values in the morning and evening. The largest and lowest amplitudes of NO2 VCDTrop diurnal variation appear in winter and in summer, respectively. The diurnal pattern at SDZ station is similar to those at other less polluted stations, but distinct from the ones at the urban or polluted stations. Tropospheric NO2 VCDs at SDZ are strongly dependent on the wind, with the higher values being associated with the pollution plumes from Beijing city. Tropospheric NO2 VCDs derived from ground-based MAX-DOAS at SDZ show to be well correlated with corresponding OMI (Ozone Monitoring Instrument) satellite products with a correlation coefficient R = 0.88. However, the OMI observations are on average higher than MAX-DOAS NO2 VCDs by a factor of 28%, probably due to the OMI grid cell partly covering the south of SDZ which is influenced more by the pollution plumes from the urban areas.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Dióxido de Nitrogênio/análise , Atmosfera/química , Pequim , Cidades , Ozônio/análise , Estações do Ano
17.
J Environ Sci (China) ; 80: 316-326, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30952349

RESUMO

The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net photosynthetic rate (NPR) of the excised branches and branches in situ were measured simultaneously by using two photosynthetic instruments to characterize the activity of the excised branches of Phyllostachys nigra. The ratio of normalized NPR of excised branches to NPR in situ was used to assess the photosynthetic activity of detached branches. Based on photosynthetic activity, an optimal hydroponics protocol for maintaining activity of excised P. nigra branches was presented: 1/8 times the concentration of Gamborg B5 vitamin mixture with pH = 6. Under the best cultivation protocol, photosynthetic activity of excised P. nigra branches could be maintained more than 90% within 6 hr in the light intensity range of 200-2000 µmol/(m2·sec) and temperature range of 13.4-28.7°C. The nitrogen dioxide (NO2) flux differences between in situ and in vitro branches and the atmosphere were compared using double dynamic chambers. Based on the maintenance method of excised branches, the NO2 exchange flux between the excised P. nigra branches and the atmosphere (from -1.01 to -2.72 nmol/(m2·sec) was basically consistent with between the branches in situ and the atmosphere (from -1.12 to -3.16 nmol/(m2 sec)) within 6 hr. Therefore, this study provided a feasible protocol for in vitro measurement of gas exchange between tall trees and the atmosphere for a period of time.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Dióxido de Nitrogênio/análise , Prunus/fisiologia , Atmosfera/química , Fotossíntese , Árvores
18.
Chemosphere ; 226: 616-624, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30954896

RESUMO

BACKGROUND: On July 1st, 2015, Hong Kong became the first city in Asia to implement a policy regulating sulfur dioxide (SO2) in shipping emissions. We conducted an accountability study assessing the improvement in ambient air quality and estimating the effect on health outcomes of the policy. METHOD: We used interrupted time series (ITS) with segmented regression to identify any change in ambient concentrations of SO2 in contrast to other ambient pollutants (particulate matter <10 µm in diameter (PM10), nitrogen dioxide (NO2) and ozone (O3)) at 10 monitoring stations in Hong Kong from 2010 to 2017. We validated these findings using cumulative sum control (CUSUM) charts. We used a validated risk assessment model to estimate effects of changes in air quality on death for natural causes, cardiovascular and respiratory diseases. RESULTS: Mean monthly concentrations of SO2 fell abruptly at the monitoring station closest to the main shipping port (Kwai Chung (KC)) by -10.0 µgm3 p-value = 0.0004, but not elsewhere. No such changes were evident for the other pollutants (PM10, NO2, O3). CUSUM charts confirmed a change in July 2015. Estimated deaths avoided per year as a result of the policy were 379, 72, 30 for all natural causes, respiratory and cardiovascular diseases respectively. CONCLUSION: Implementation of the shipping emission policy in Hong Kong successfully reduced ambient SO2, with the potential to reduce mortality. However, to gain full benefits, restrictions on shipping emissions need to be implemented throughout the region.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/legislação & jurisprudência , Comércio/legislação & jurisprudência , Monitoramento Ambiental/métodos , Material Particulado/análise , Dióxido de Enxofre/análise , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Hong Kong/epidemiologia , Humanos , Pneumopatias/epidemiologia , Pneumopatias/mortalidade , Dióxido de Nitrogênio/análise , Ozônio/análise , Responsabilidade Social
19.
Environ Pollut ; 250: 14-22, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30981931

RESUMO

While exposure to places with higher greenness shows health benefits, evidence is scarce on its lipidemic effects. We assessed the associations between residential greenness and blood lipids and effect mediations by air pollution, physical activity, and adiposity in China. Our study included 15,477 adults from the population-based 33 Communities Chinese Health Study, conducted between April and December 2009, in Northeastern China. We measured total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Residential greenness was estimated using two satellite-derived vegetation indices - the Normalized Difference Vegetation Index (NDVI) and the Soil Adjusted Vegetation Index (SAVI). We used both nitrogen dioxide (NO2) and particles ≤2.5 µm in aerodynamic diameter (PM2.5) as proxies of outdoor air pollution. Associations were assessed using linear mixed effects regression models and logistic mixed effects regression models, and mediation analyses were also performed. Living in higher greenness areas was consistently associated with lower TC, TG, and LDL-C levels and higher HDL-C levels (e.g., change in TC, TG, LDL-C, and HDL-C per 0.1-unit increase in NDVI500-m was -1.52%, -3.05%, -1.91%, and 0.52%, respectively). Similar results were obtained for the corresponding dyslipidemias. These associations were generally stronger in women and older adults. While educational levels showed effect modifications, the effect pattern was inconsistent. Both outdoor air pollution and body mass index mediated 9.1-62.3% and 5.6-40.1% of the associations for greenness and blood lipids, respectively, however, physical activity did not. Our results suggest beneficial associations between residing in places with higher greenness and blood lipid levels, especially in women and the elder individuals. The associations were partly mediated by lower air pollution and adiposity.


Assuntos
Poluição do Ar/análise , Ambiente Construído , Exposição Ambiental/análise , Lipídeos/sangue , População Urbana , Adiposidade , Idoso , Poluição do Ar/efeitos adversos , Índice de Massa Corporal , China , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Obesidade/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-31022858

RESUMO

Crop straw burning frequently occurs in Central China, where agriculture is highly productive. We carried out a two-month observation on straw burning in Hubei Province from September 1 to October 31, 2015 to track the variations of air pollutants and comprehensively quantify their influence on regional air quality. Results showed that the concentration of suspended particles (particles smaller than 2.5 or 10 µm, i.e., PM2.5/PM10) and gas pollutants including ozone (O3), sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO) was significantly enhanced with the increasing number of fire spots. The average daily concentrations of PM10, PM2.5 and O3 during the intensive burning period (from October 12 to 25) exceeded the daily limits published by the World Health Organization (WHO) by 101.8, 72.7 and 59.1 µg/m3, respectively. In the hourly distribution of pollutant concentration, PM10, PM2.5, O3, SO2, NO2 and CO were 63.49%, 46.29%, 65.56%, 64.40%, 48.57% and 13.49% higher during burning periods than during non-burning periods. Statistical results based on the air quality index (AQI) indicated that biomass burning was the key factor for the deterioration of local air quality, with a contribution ratio exceeding 41%. Additionally, the pollutants were more spatially homogeneous during the burning period than during the non-burning period. Straw burning not only worsened the local air quality but also raised the pollution level of surrounding regions due to the transport of air mass.


Assuntos
Agricultura/métodos , Poluição do Ar/análise , Fogo , Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , China , Monitoramento Ambiental , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Dióxido de Enxofre/análise
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