Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.603
Filtrar
1.
Chemosphere ; 257: 127315, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32535364

RESUMO

The study was conducted to assess the performance of improved and traditional cookstoves using wood as a fuel and three combinations of other fuel mixes - (i) wood and cow dung, (ii) wood and mustard stalks, and (iii) cow dung and mustard stalks). Energy and emission parameters such as specific energy consumption (SEC), emission factors (EFs) of carbon monoxide (CO), particulate matter (PM) and black carbon (BC) were used to compare four different types of cookstoves. These included top-feed forced draft (TF-FD), top-feed natural draft (TF-ND), front-feed natural draft (FF-ND) and front-feed traditional (FF-TR) cookstoves. Controlled cooking test (CCT) was used as the test protocol. The results showed the performance of improved cookstove technologies can vary based on the fuel used for cooking. It was observed that emission factors for PM and CO increased by 67-96% and 45-90% respectively when all three improved cookstoves were tested with three fuel combinations against wood as cooking fuel. Among the tested cookstoves, a marked difference was observed between performance of forced draft and natural draft cookstoves. Forced draft cookstoves emitted higher amount of all pollutant emissions compared to natural draft cookstoves when used with mustard stalks in combination with either wood or cowdung. The results are of critical importance given that forced draft cookstoves have been promoted in geographical regions where fuel mix use is prevalent. Therefore, forced draft cookstove might not be the right choice when the goal is climate mitigation and reduction in impact on human health. It is imperative to study comprehensively the influence of various field variables on performance of cookstoves, which have severe implications on the performance of cookstoves.


Assuntos
Poluentes Atmosféricos/análise , Culinária/métodos , Poluição do Ar em Ambientes Fechados/análise , Monóxido de Carbono/análise , Utensílios Domésticos , Índia , Material Particulado/análise , Fuligem , Tecnologia , Madeira/química
2.
Sci Total Environ ; 736: 139658, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32492613

RESUMO

Since its first appearance in Wuhan, China at the end of 2019, the new coronavirus (COVID-19) has evolved a global pandemic within three months, with more than 4.3 million confirmed cases worldwide until mid-May 2020. As many countries around the world, Malaysia and other southeast Asian (SEA) countries have also enforced lockdown at different degrees to contain the spread of the disease, which has brought some positive effects on natural environment. Therefore, evaluating the reduction in anthropogenic emissions due to COVID-19 and the related governmental measures to restrict its expansion is crucial to assess its impacts on air pollution and economic growth. In this study, we used aerosol optical depth (AOD) observations from Himawari-8 satellite, along with tropospheric NO2 column density from Aura-OMI over SEA, and ground-based pollution measurements at several stations across Malaysia, in order to quantify the changes in aerosol and air pollutants associated with the general shutdown of anthropogenic and industrial activities due to COVID-19. The lockdown has led to a notable decrease in AOD over SEA and in the pollution outflow over the oceanic regions, while a significant decrease (27% - 30%) in tropospheric NO2 was observed over areas not affected by seasonal biomass burning. Especially in Malaysia, PM10, PM2.5, NO2, SO2, and CO concentrations have been decreased by 26-31%, 23-32%, 63-64%, 9-20%, and 25-31%, respectively, in the urban areas during the lockdown phase, compared to the same periods in 2018 and 2019. Notable reductions are also seen at industrial, suburban and rural sites across the country. Quantifying the reductions in major and health harmful air pollutants is crucial for health-related research and for air-quality and climate-change studies.


Assuntos
Poluição do Ar/análise , Infecções por Coronavirus , Monitoramento Ambiental , Pandemias , Pneumonia Viral , Ásia Sudeste , Betacoronavirus , Monóxido de Carbono/análise , Humanos , Malásia , Dióxido de Nitrogênio/análise , Oceanos e Mares , Material Particulado/análise , Dióxido de Enxofre
3.
Chemosphere ; 253: 126668, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278917

RESUMO

BACKGROUND: Congenital heart defects (CHDs) has a multifactorial causation with a strong genetic component and many environmental triggers. Emerging body of empirical studies suggest that air pollution is an important contributor to the development of CHDs, however, there still remains some controversy over the current evidence, and to the authors' knowledge, no studies have reviewed the most recent evidence. OBJECTIVES: We performed a systematic review and meta-analysis of epidemiological literature to investigate the relationship between maternal air pollution exposure and CHDs risk in offspring. The presence of heterogeneity and publication bias across available studies were also examined. METHODS: An extensive literature search of epidemiological studies pertaining to air pollution and CHDs, published in English language, until August 1, 2019 was conducted. Summary risk estimates of pollution-outcome combinations were calculated for i) risk per specific increment of concentration and ii) risk at high versus low exposure level in each study using fixed-effect model or random-effects model. RESULTS: A total of 26 studies were finally included. In the meta-analyses, high versus low carbon monoxide (CO) exposure was associated with an increased risk of tetralogy of Fallot [odds ratio (OR) = 1.21, 95% confidence interval (CI): 1.04-1.41], yet particulate matter ≤ 5 µm (PM2.5) exposure was marginally associated with it. Increased risk of atrial septal defects (ASDs) was found for each 10 µg/m3 and 10 ppb increment in particulate matter ≤ 10 µm (PM10) and ozone (O3) exposure, respectively (OR = 1.04, 95% CI: 1.00-1.09; OR = 1.09, 95% CI: 1.02-1.17). Categorical nitrogen dioxide (NO2) exposure was associated with an increased risk of coarctation of the aorta (OR for high versus low = 1.14, 95% CI: 1.02-1.26). Analyses for other combinations yielded none statistically significant associations. Sensitive analyses showed similar findings. CONCLUSIONS: The summary effect estimates from this study suggest statistically significant associations between increased risk of specific CHDs subtypes and PM2.5, PM10, NO2, CO, and O3 exposures. Further studies, especially conducted in developing countries, with improvements in exposure assessing, outcome harmonizing, and mechanistic understanding are needed to elaborate the suggestive associations.


Assuntos
Poluição do Ar/estatística & dados numéricos , Cardiopatias Congênitas/epidemiologia , Exposição Materna/estatística & dados numéricos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monóxido de Carbono/análise , Exposição Ambiental/análise , Feminino , Cardiopatias Congênitas/induzido quimicamente , Humanos , Dióxido de Nitrogênio/análise , Razão de Chances , Ozônio/análise , Material Particulado/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-32295485

RESUMO

Despite a connection between road traffic and air pollution has been clearly identified, few integrated analyses on air quality and mobility policies are currently available worldwide. Aim of this work is to build a framework for the evaluation of the impact of mobility policies on air quality in 14 major Italian cities, on a long-time scale (2006-2016). Air quality data was collected from all PM10, PM2.5, and NO2 monitoring stations, installed in compliance with the European directive 2008/50/EC. A large dataset was collected, including public transport, environmental, and fuel categorization of the private vehicular fleet, low emissions zones and modal split. In the analyzed time period, both public transportation use and private motorization decreased. Considering the environmental classification standards of vehicles, Northern cities are more readily switching to newer and less polluting cars (e.g. Euro 5 and Euro 6). There has been a general reduction in PM and NO2 concentration. Nevertheless, exceedances are still above the targeted limit value, mainly in some Northern cities who made major investments in sustainable and shared mobility: this highlights a strong influence of climatic conditions and other sources. Dramatic variations in the CO/NO ratio were observed in Turin, while smaller changes are observed in Milan, Rome and Palermo.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Emissões de Veículos/análise , Automóveis , Monóxido de Carbono/análise , Cidades , Itália , Óxido Nítrico/análise
5.
Sud Med Ekspert ; 63(2): 41-46, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32297498

RESUMO

In this article, we consider features of the referral of biological material and assessment of medical and legal chemical researches at emergencies of technogenic character, plane crashes, the fires with the numerous human victims. Practical recommendations on obtaining of biological material for a research on volatile organic compounds, including ethyl alcohol and its metabolites, volatile products of burning, including monoxide of carbon and cyanides are made. Features and the recommended order of conducting judicial and chemical examination at emergencies are designated.


Assuntos
Emergências , Manejo de Espécimes , Monóxido de Carbono/análise , Cianetos/análise , Etanol/análise , Fogo , Humanos , Compostos Orgânicos Voláteis/análise
6.
Medicine (Baltimore) ; 99(7): e19109, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049823

RESUMO

BACKGROUND: Mild hemolysis is difficult to determinate by traditional methods, and its role in Gilbert's syndrome (GS) is unclear. The main aims were to inspect the erythrocyte (RBC) survival in GS by using Levitt's carbon monoxide (CO) breath test and to assess its contribution to unconjugated hyperbilirubinemia. METHODS: Fifty subjects with GS and 1 with type-II Crigler-Najjar syndrome (CN2) received RBC lifespan measurement with Levitt's CO breath test. Mean RBC lifespan was compared with normal referral value. Correlations of serum total bilirubin (TB) with RBC lifespan, blood panel data, demographic factors, and uridine diphosphate glucuronosyltransferase (UGT1A1) mutation load were calculated by Spearman analysis. Susceptibility factors for mild hemolysis were analyzed by multivariate regression analysis. RESULTS: The mean RBC lifespan of the GS subjects was significantly shorter than the normal reference value (95.4 ±â€Š28.9 days vs 126 days; t = -7.504, P < .01), with 30.0% below the lower limit of the normal reference range (75 days). The RBC lifespan of the participant with CN2 was 82 days. Serum TB correlated positively with UGT1A1 mutation load (γ = 0.281, P = .048), hemoglobin (γ = .359, P = .010) and hematocrit (γ = 0.365, P = .010), but negatively with RBC lifespan (γ = -0.336, P = .017). No significant susceptibility factors for mild hemolysis were found. CONCLUSIONS: The results indicate that mild hemolysis indeed, exists in a portion of patients with GS and might serve as an important contributor to unconjugated hyperbilirubinemia in addition to UGT1A1 polymorphism. Further studies on the mechanism and the potential risks in various medical treatments might be wanted.


Assuntos
Monóxido de Carbono/análise , Doença de Gilbert/complicações , Hemólise , Hiperbilirrubinemia/etiologia , Adulto , Testes Respiratórios/instrumentação , Eritrócitos/fisiologia , Feminino , Humanos , Hiperbilirrubinemia/sangue , Masculino , Pessoa de Meia-Idade
7.
PLoS One ; 15(2): e0228535, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32069301

RESUMO

National-scale empirical models for air pollution can include hundreds of geographic variables. The impact of model parsimony (i.e., how model performance differs for a large versus small number of covariates) has not been systematically explored. We aim to (1) build annual-average integrated empirical geographic (IEG) regression models for the contiguous U.S. for six criteria pollutants during 1979-2015; (2) explore systematically the impact on model performance of the number of variables selected for inclusion in a model; and (3) provide publicly available model predictions. We compute annual-average concentrations from regulatory monitoring data for PM10, PM2.5, NO2, SO2, CO, and ozone at all monitoring sites for 1979-2015. We also use ~350 geographic characteristics at each location including measures of traffic, land use, land cover, and satellite-based estimates of air pollution. We then develop IEG models, employing universal kriging and summary factors estimated by partial least squares (PLS) of geographic variables. For all pollutants and years, we compare three approaches for choosing variables to include in the PLS model: (1) no variables, (2) a limited number of variables selected from the full set by forward selection, and (3) all variables. We evaluate model performance using 10-fold cross-validation (CV) using conventional and spatially-clustered test data. Models using 3 to 30 variables selected from the full set generally have the best performance across all pollutants and years (median R2 conventional [clustered] CV: 0.66 [0.47]) compared to models with no (0.37 [0]) or all variables (0.64 [0.27]). Concentration estimates for all Census Blocks reveal generally decreasing concentrations over several decades with local heterogeneity. Our findings suggest that national prediction models can be built by empirically selecting only a small number of important variables to provide robust concentration estimates. Model estimates are freely available online.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/estatística & dados numéricos , Modelos Estatísticos , Poluição do Ar/história , Poluição do Ar/estatística & dados numéricos , Monóxido de Carbono/análise , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental/história , Geografia , História do Século XX , História do Século XXI , Humanos , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Análise de Regressão , Análise Espacial , Dióxido de Enxofre/análise , Fatores de Tempo , Estados Unidos/epidemiologia
8.
Nat Commun ; 11(1): 408, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964865

RESUMO

Biological systems are known to spontaneously adjust the functioning of neurotransmitters, ion channels, and the immune system, being promoted or regulated through allosteric effects or inhibitors, affording non-linear responses to external stimuli. Here we report that an insulated conjugated bimetallopolymer, in which Ru(II) and Pt(II) complexes are mutually connected with insulated conjugations, exhibits phosphorescence in response to CO gas. The net profile corresponds to a sigmoidal response with a dual self-controlling system, where drastic changes were exhibited at two threshold concentrations. The first threshold for activation of the system is triggered by the depolymerization of the non-radiative conjugated polymer to luminescent monomers, while the second one for regulation is triggered by the switch in the rate-determining step of the Ru complex. Such a molecular design with cooperative multiple transition metals would provide routes for the development of higher-ordered artificial molecular systems bearing bioinspired responses with autonomous modulation.


Assuntos
Materiais Biomiméticos/química , Complexos de Coordenação/química , Polímeros/química , Materiais Inteligentes/química , Monóxido de Carbono/análise , Luminescência , Platina/química , Rutênio/química , alfa-Ciclodextrinas/química
9.
Environ Pollut ; 257: 113598, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31753631

RESUMO

Air pollution is one of the most important branches of environmental science as it affects human health, climate and ecosystems. Emissions of air pollutants from transport (vehicles and ships) in port cities strongly affect air quality at local scales, warranting for a combination of theoretical and experimental studies to identify pollution hotspots. The purpose of this paper is to provide a methodology for developing a hybrid emission inventory from transport sector for two port cities located respectively on the Northern Aegean islands of Chios and Lesvos. Emission inventories were constructed for the year 2014 based on top-down and bottom-up approaches. Official data from local authorities and survey results were used for the calculation of emissions. Traffic emissions were spatially allocated to the road network based on population data and hourly traffic counts, and distributed over time (on an hourly basis) with the use of local temporal coefficients. Regarding carbon monoxide road emissions, the highest quantities are mainly emitted by Passenger Cars (43%,32% in Chios and Lesvos respectively) while for PM10 emissions, trucks have the largest share (66% in Chios and 86% in Lesvos). The pollutants that are emitted in greater quantities from the ships at the ports of Mytilene and Chios are NOx, followed by SO2 and CO. Most of the ship emissions in the ports occur by the ships at berth, as they remain berthed for hours whereas maneuvering lasts 15-20 min. As for the daily contribution of the two transport sources to the pollution profile of Mytilene, road emissions are higher for almost all pollutants. However, the contribution of ship emissions is not negligible, especially during the touristic period when marine traffic increases and emissions close to the port area become more important than those from road transport.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Emissões de Veículos/análise , Monóxido de Carbono/análise , Cidades , Ecossistema , Grécia , Veículos Automotores , Navios
10.
Indoor Air ; 30(2): 361-369, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31724228

RESUMO

Lavash is a traditional flatbread commonly baked at home by women in Armenia and other Middle Eastern and Caucasus countries. The baking process follows centuries' old recipes and is done primarily in open fire ovens. Data are limited regarding the impact of baking on indoor air quality and health outcomes. This study aimed at assessing the effects of lavash baking on household air pollution and cardiovascular outcomes among women who bake lavash in rural Armenia. A convenience sample of 98 bakers, all women, never-smokers, representing 36 households were enrolled. Carbon monoxide (CO) concentrations and carboxyhemoglobin (COHb) levels were monitored before, during, and/or after baking. As expected, exposure to concentrations of CO peaking at/or above 35-ppm during baking was more likely to occur in homes with fully enclosed and poorly ventilated baking rooms, compared to those with three or fewer walls and/or one or more windows. Bakers in homes where CO concentrations peaked at/or above 35-ppm were more likely to have an increase in post-baking COHb levels compared to those in homes with lower CO concentrations.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monóxido de Carbono/análise , Carboxihemoglobina/metabolismo , Exposição Ambiental/estatística & dados numéricos , Armênia , Pão , Culinária/métodos , Culinária/estatística & dados numéricos , Feminino , Humanos , População Rural
11.
Artigo em Inglês | MEDLINE | ID: mdl-31674258

RESUMO

Solketal is a promising oxygenate additive that can be chemically derived from bioglycerol. Emulsification by a microwave-irradiating method was used to prepare the micro- and nanoemulsions of solketal dispersed in continuous ultra-low sulfur diesel (ULSD) due to the immiscibility of solketal with ULSD. The emissions from a direct-injection, four-stroke and naturally aspirated diesel engine fueled with each of these emulsions, and with neat ULSD, were analyzed and compared. The experimental results show that the nanoemulsion and microemulsions were successfully produced. In addition, an increasing engine speed resulted in lower NOx, CO and O2 but higher CO2 emissions. The nanoemulsion was found to produce the lowest NOx emission while neat ULSD produced the highest NOx emission among these three test fuels. The lowest CO emission was formed by fueling the micro-emulsion of dispersed solketal-in-ULSD. Moreover, the burning of the nanoemulsion in the diesel engine formed the highest CO2 along with the lowest O2 emissions. Hence, the nanoemulsion had the highest burning efficiency among the three test fuels for the diesel engine.


Assuntos
Dioxolanos/química , Emulsões/química , Gasolina , Emissões de Veículos/análise , Biocombustíveis , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Micro-Ondas , Óxidos de Nitrogênio/análise , Enxofre/química
12.
Chemosphere ; 243: 125357, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31760286

RESUMO

It remains unknown whether ambient air pollution could induce the onset of acute aortic dissection (AAD). This study aimed to investigate the potential association between fine particulate matter (PM2.5) and AAD onset. We collected new episodes of AAD between January 1, 2014 and December 31, 2018 from the emergency department of a major hospital in Shanghai, China. The overdispersed generalized additive model was used to estimate the association between PM2.5 and AAD emergency hospitalizations and was adjusted for time trends and weather conditions. During the study period, we identified a total of 1335 cases of AAD hospitalizations and recorded an average PM2.5 concentration of 45 ±â€¯30 µg/m3. The association was statistically significant on the concurrent day of hospital admission, remained on the lag 1 day. For the average of the two lags, a 10 µg/m3 increase of PM2.5 was associated with 3.38% (95% confidence interval: 1.02%, 5.79%) increase of AAD hospitalizations. The association between PM2.5 and AAD remained when adjusting for the concomitant exposures to coarse particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ozone. The concentration-response curves increased apparently when daily PM2.5 concentration was beyond the China's National Ambient Air Quality Standard (35 µg/m3). In stratified analyses, the significant association was only present among elders and males, and during cool season. This investigation demonstrated a significant and robust association between short-term PM2.5 exposure and increased AAD hospitalizations in Shanghai, China. Our findings have important implications for the prevention of AAD.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Aneurisma Dissecante/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Material Particulado/análise , Idoso , Poluição do Ar/análise , Monóxido de Carbono/análise , China/epidemiologia , Hospitalização , Humanos , Masculino , Dióxido de Nitrogênio/análise , Ozônio/análise , Estações do Ano , Dióxido de Enxofre/análise , Tempo (Meteorologia)
13.
Arch Environ Contam Toxicol ; 78(1): 79-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31832738

RESUMO

Mixing ratios of atmospheric ammonia (NH3), nitric oxide (NO), carbon monoxide (CO), nonmethane hydrocarbons (NMHCs), and methane (CH4) were measured to investigate the vehicular emissions, which are a dominant source of atmospheric NH3 in urban sites of Delhi, India from January 2013 to December 2014. The annual average mixing ratios of NH3, NO, CO, NMHCs, and CH4 were 21.2 ± 2.1 ppb, 21.2 ± 6.1 ppb, 1.89 ± 0.18 ppm, 0.67 ± 0.21 ppm and 3.11 ± 0.53 ppm, respectively. Considering NO as a tracer of vehicular plume, ambient NH3 was correlated with NO during peak traffic hour in the morning (7:00-10:00 h) and evening (17:00-19:00 h) and observed significant positive correlation between them. Result reveals that the mixing ratio of atmospheric NH3 significantly positive correlated with traffic related pollutants (NO, CO, and NHHCs) during all the seasons (winter, summer, and monsoon). During winter, the average mixing ratio of atmospheric NH3 was increased by 1.2-3.5 ppb in the morning peak hour, whereas increased by 0.3-1.6 ppb in the evening peak hour. Similarly, an increase in NH3 mixing ratio was observed during summer (morning: 1.2-2.7 ppb and evening: 1.5-1.6 ppb) and monsoon (morning: 0.4-3.6 ppb and evening: 0.9-1.4 ppb) seasons. The results emphasized that the traffic could be one of the dominant source of ambient NH3 at the urban site of Delhi, as illustrated by positive relationships of NH3 with traffic related co-pollutants (NO, CO and NMHCs).


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Monóxido de Carbono/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Óxidos de Nitrogênio/análise , Emissões de Veículos/análise , Cidades , Índia , Óxido Nítrico/análise , Dióxido de Nitrogênio/análise , Estações do Ano
14.
Artigo em Inglês | MEDLINE | ID: mdl-31717386

RESUMO

This retrospective study evaluates the effect of a telemedicine program developed in the central Catalan region in lowering the environmental footprint by reducing the emission of atmospheric pollutants, thanks to a reduction in the number of hospital visits involving journeys by road. Between January 2018 and June 2019, a total of 12,322 referrals were made to telemedicine services in the primary care centers, avoiding a total of 9034 face-to-face visits. In total, the distance saved was 192,682 km, with a total travel time saving of 3779 h and a total fuel reduction of 11,754 L with an associated cost of €15,664. This represents an average reduction of 3248.3 g of carbon dioxide, 4.05 g of carbon monoxide, 4.86 g of nitric oxide and 3.2 g of sulphur dioxide. This study confirms that telemedicine reduces the environmental impact of atmospheric pollutants emitted by vehicles by reducing the number of journeys made for face-to-face visits, and thus contributing to environmental sustainability.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Telemedicina , Emissões de Veículos/análise , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Humanos , Estudos Retrospectivos , Viagem
15.
Environ Monit Assess ; 191(11): 693, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667634

RESUMO

Exposure to air pollutants and heat stress from traditional cooking fires is the leading cause of mortality and morbidity in low- and middle-income countries globally and have an adverse effect on the environment. According to the World Health Organization, 3.8 million people die annually prematurely from illness related to household air pollution. Families living in poverty are at the highest risk, especially women and children. In this study, exposure to particulate matter (PM2.5 and PM10), carbon monoxide (CO) and nitrogen dioxide (NO2) was measured among resource-poor women cassava processors. The test locations were chosen in the peri-urban settlements of Abeokuta in the Ogun State of Nigeria, where household women entrepreneurs roast garri (granulated cassava) for sale in the local market. The measurements were taken for two types of stoves which are generally existing in the study location. First, a rectangular stove (RS) with two operators and, second, a circular stove (CS) with one operator; both stoves used wood as fuel. The emissions were compared with a modern mechanical liquefied petroleum gas burner-based garri roaster (GS). Hours spent per day in front of garri stoves ranged from 6 to 12 h for both stoves, with a frequency of 1 to 3 days of operation per week. It was found that CS operators were spending significantly more time in producing garri, which is due to the low capacity of the CS. The average PM2.5 concentrations for RS and CS were 381 and 273 µg/m3, respectively, estimated to be 21 and 41 µg/m3 on an annual mean level basis. Similarly, for PM10, the mean concentration levels were 1580 and 594 µg/m3 for RS and CS, respectively. The annual mean levels for PM10 were about 89 µg/m3 for both types of stoves. CO exposure during garri processing was up to five times higher than the recommended concentrations with a 4-h mean of 48 and 50 mg/m3 for RS and CS, respectively. NO2 levels were very low, ~ 0 ppm. This investigative research concluded that wood-fired small-scale garri producers in Nigeria are exposed to very unhealthy levels of PM, CO and thermal stress. The concentration levels of both PM and CO were exceeding the global as well as Nigerian ambient air quality standard regulations. Along with air pollution, thermal stress was a significant issue, which is known to exacerbate the negative effect of air pollution on the human body.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Transtornos de Estresse por Calor/epidemiologia , Resposta ao Choque Térmico , Manihot , Adulto , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monóxido de Carbono/análise , Criança , Culinária , Monitoramento Ambiental , Características da Família , Feminino , Fogo , Indústria Alimentícia , Humanos , Nigéria , Dióxido de Nitrogênio , Material Particulado/análise , Madeira/química
16.
Sensors (Basel) ; 19(21)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683797

RESUMO

While working on fire ground, firefighters risk their well-being in a state where any incident might cause not only injuries, but also fatality. They may be incapacitated by unpredicted falls due to floor cracks, holes, structure failure, gas explosion, exposure to toxic gases, or being stuck in narrow path, etc. Having acknowledged this need, in this study, we focus on developing an efficient portable system to detect firefighter's falls, loss of physical performance, and alert high CO level by using a microcontroller carried by a firefighter with data fusion from a 3-DOF (degrees of freedom) accelerometer, 3-DOF gyroscope, 3-DOF magnetometer, barometer, and a MQ7 sensor using our proposed fall detection, loss of physical performance detection, and CO monitoring algorithms. By the combination of five sensors and highly efficient data fusion algorithms to observe the fall event, loss of physical performance, and detect high CO level, we can distinguish among falling, loss of physical performance, and the other on-duty activities (ODAs) such as standing, walking, running, jogging, crawling, climbing up/down stairs, and moving up/down in elevators. Signals from these sensors are sent to the microcontroller to detect fall, loss of physical performance, and alert high CO level. The proposed algorithms can achieve 100% of accuracy, specificity, and sensitivity in our experimental datasets and 97.96%, 100%, and 95.89% in public datasets in distinguishing between falls and ODAs activities, respectively. Furthermore, the proposed algorithm perfectly distinguishes between loss of physical performance and up/down movement in the elevator based on barometric data fusion. If a firefighter is unconscious following the fall or loss of physical performance, an alert message will be sent to their incident commander (IC) via the nRF224L01 module.


Assuntos
Sistemas Computacionais , Bombeiros , Aceleração , Acidentes por Quedas , Algoritmos , Altitude , Monóxido de Carbono/análise , Carboxihemoglobina/análise , Bases de Dados como Assunto , Humanos , Monitorização Ambulatorial , Processamento de Sinais Assistido por Computador , Estados Unidos
17.
Environ Int ; 133(Pt B): 105233, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31678904

RESUMO

Evidence regarding the association of specific air pollutants with vascular dementia (VaD) risk is limited. In this nested case-control study, we enrolled 831 adults aged >65 years with VaD (International Classification of Diseases, Ninth Revision, Clinical Modification code 290.4x) newly diagnosed during 2005-2013; 3324 controls were age-, sex-, and VaD diagnosis year-matched with the study patients. Both patients with VaD and controls were selected from among a cohort of one million beneficiaries of Taiwan's National Health Insurance program, all of whom were registered in 2005. Exposure to the mean daily air pollutant concentration, derived from 76 fixed air quality monitoring stations, in 3, 5, and 7 years before VaD diagnosis was assessed using the spatial analysis method (i.e., ordinary kriging) on ArcGIS. A logistic regression model was used to calculate covariate-adjusted odds ratios (ORs) of VaD in relation to specific air pollutants. After potential confounders and other air pollutants were controlled for, high concentrations of coarse particulate matter (10 µm or less in diameter) and carbon monoxide (CO) were sporadically associated with higher OR of VaD. The most prominent association was observed for nitrogen dioxide (NO2) exposure within 5 and 7 years before diagnosis. Compared with the <25th percentile of NO2 exposure, the 25th-50th, 50th-75th, and >75th percentiles of NO2 exposure significantly increased ORs (95% confidence intervals): 1.62 (1.28-2.23), 1.61 (1.11-2.33), and 2.22 (1.35-3.65) within 5 years before diagnosis, respectively, and 1.59 (1.20-2.11), 1.65 (1.15-2.37), and 2.05 (1.28-3.28) within 7 years before diagnosis, respectively. We found that higher NO2 exposure in the past was significantly associated with an elevated risk of VaD. Although less consistent, higher exposure to CO was also associated with a higher risk of VaD. Most NO2 in cities originates from motor vehicle exhaust; other sources of NO2 are petrol and metal refining, electricity generation from coal-fired power stations, other manufacturing industries, and food processing. Future studies should investigate associations of VaD with specific sources of NO2.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Demência Vascular/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Monóxido de Carbono/análise , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/análise , Razão de Chances , Material Particulado/análise , Taiwan , Emissões de Veículos/análise
18.
Artigo em Inglês | MEDLINE | ID: mdl-31771182

RESUMO

As a non-invasive method, heart rate variability (HRV) has been widely used to study cardiovascular autonomous control. Environmental epidemiological studies indicated that the increase in an average concentration of particulate matter (PM) would result in a decrease in HRV, which was related to the increase of cardiovascular mortality in patients with myocardial infarction and the general population. With rapid economic and social development in Asia, how air pollutants, such as PM of different sizes and their components, affect the cardiovascular health of older people, still need to be further explored. The current study includes a 72 h personal exposure monitoring of seven healthy older people who lived in the Taipei metropolitan area. Mobile equipment, a portable electrocardiogram recorder, and the generalized additive mixed model (GAMM) were adopted to evaluate how HRV indices were affected by size-fractionated PM, particle-bound polycyclic aromatic hydrocarbons (p-PAHs), black carbon (BC), and carbon monoxide (CO). Other related confounding factors, such as age, sex, body mass index (BMI), temperature, relative humidity (RH), time, and monitoring week were controlled by fixed effects of the GAMM. Statistical analyses of multi-pollutant models showed that PM2.5-10, PM1, and nanoparticle (NP) could cause heart rate (HR), time-domain indices, and frequency-domain indices to rise; PM1-2.5 and BC would cause the frequency-domain index to rise; p-PAHs would cause HR to rise, and CO would cause time-domain index and frequency-domain index to decline. In addition, the moving average time all fell after one hour and might appear at 8 h in HRVs' largest percentage change caused by each pollutant, results of which suggested that size-fractionated PM, p-PAHs, BC, and CO exposures have delayed effects on HRVs. In conclusion, the results of the study showed that the increase in personal pollutant exposure would affect cardiac autonomic control function of healthy older residents in metropolitan areas, and the susceptibility of cardiovascular effects was higher than that of healthy young people. Since the small sample size would limit the generalizability of this study, more studies with larger scale are warranted to better understand the HRV effects of simultaneous PM and other pollution exposures for subpopulation groups.


Assuntos
Carbono/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Nanopartículas/toxicidade , Material Particulado/toxicidade , Adolescente , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono/química , Monóxido de Carbono/análise , Poluentes Ambientais/análise , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Tamanho da Partícula , Hidrocarbonetos Policíclicos Aromáticos/análise , Taiwan
19.
Environ Pollut ; 255(Pt 2): 113260, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31622808

RESUMO

Emissions from ships at berth are small compared to the total ship emissions; however, they are one of the main contributors to pollutants in the air of densely-populated areas, consequently heavily affecting public health. This is due to auxiliary marine engines being used to generate electric power and steam for heating and providing services. The present study has been conducted on an engine representative of a marine auxiliary, which was a heavy duty, six-cylinder, turbocharged and after-cooled engine with a high pressure common rail injection system. Engine performance and emission characterisations during cold start are the focus of this paper, since cold start is significantly influential. Three tested fuels were used, including the reference diesel and two IMO (International Maritime Organization) compliant spiked fuels. The research engine was operated at a constant speed and 25% load condition after 12 h cooled soak. Results show that during cold start, significant heat generated from combustion is used to heat the engine block, coolant and lubricant. During the first minute, compared to the second minute, emissions of particle number (PN), carbon monoxide (CO), particulate matter (PM), and nitrogen oxides (NOx) were approximately 10, 4, 2 and 1.5 times higher, respectively. The engine control unit (ECU) plays a vital role in reducing engine emissions by changing the engine injection strategy based on the engine coolant temperature. IMO-compliant fuels, which were higher viscosity fuels associated with high sulphur content, resulted in an engine emission increase during cold start. It should be taken into account that auxiliary marine diesel engines, working at partial load conditions during cold start, contribute considerably to emissions in coastal areas. It demonstrates a need to implement practical measures, such as engine pre-heating, to obtain both environmental and public health advantages in coastal areas.


Assuntos
Automóveis , Temperatura Baixa , Gasolina/análise , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Óxidos de Nitrogênio/análise , Material Particulado/análise , Navios , Enxofre/análise , Temperatura
20.
Zhonghua Nei Ke Za Zhi ; 58(10): 777-781, 2019 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-31594177

RESUMO

Objective: To detect the red blood cell lifespan in patients with polycythemia vera (PV), and explore the influencing factors. Methods: From February 2017 to December 2018, 27 patients with PV at Blood Diseases Hospital, Chinese Academy of Medical Science and 18 normal controls were recruited. Red blood cell lifespan was detected by endogenous carbon monoxide (CO) breath test. The related factors were analyzed. Results: The average red blood cell lifespan of 27 PV patients was 80 (range, 35-120) days (d), which was significantly shorter than that of the normal controls [110.5(69-166) d, P<0.05], namely 35.3 d shorter. The red blood cell lifespan of ten newly diagnosed patients and 17 patients who were treated with hydroxyurea and/or interferon were 98 (35-117) d and 69 (45-120) d, respectively, which were both shorter than that of the normal control (P=0.010, 0.000). Correlation analysis showed that red blood cell lifespan of patients with newly diagnosed PV was associated with JAK2 mutation allele burden (r=0.900, P=0.037), peripheral blood lymphocyte count (r=-0.742, P=0.014) and the level of serum vitamin B(12) (r=-0.821, P=0.023). Conclusion: The lifespan of red blood cells in patients with PV is about one-third shorter than normal, and is related to JAK2 mutation allele burden, absolute lymphocyte count, and serum vitamin B(12) level.


Assuntos
Testes Respiratórios/métodos , Monóxido de Carbono/análise , Monóxido de Carbono/metabolismo , Eritrócitos/patologia , Policitemia Vera/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Contagem de Eritrócitos , Feminino , Humanos , Janus Quinase 2 , Longevidade , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA