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1.
Burns ; 47(3): 728-732, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33153813

RESUMEN

INTRODUCTION: As recently as 2006, carburetor flash burns comprised as much as 27% of admissions for car-related burns, despite the fact carburetors were last installed in pre-1990 automobiles. The prevalence of this injury pattern is related to the estimated 14 million cars on the road today that were manufactured prior to that year. The aim of this study was to investigate modern sources of automotive burns and describe any new trends in automotive burn-related epidemiology. MATERIALS AND METHODS: A retrospective review was conducted of all burn admissions from the years 2009-2013 to identify patients who suffered automotive-related burns. Pediatric patients (<18 years old) were excluded. Demographic information including age, gender, mechanism of injury, occupation, TBSA, number of operations, and length of hospital stay were recorded. RESULTS: From 2009-2013, the burn center saw 83 admissions for automotive-related burns. 14.5% of patients were mechanics. The most common injury pattern was from radiator burns (47%), followed by gasoline related burns (30%). There were only two carburetor burns (2.4%). 67.4% of patients were treated for less than two hospital days and there was one death (1.2% mortality). CONCLUSION: Despite the removal of carburetors from engines and a decrease in this specific mechanism, a significant morbidity remains with gasoline-inflicted burns. More public awareness is needed for the safe removal of radiator caps and handling of chemicals in overheating engines.


Asunto(s)
Automóviles/estadística & datos numéricos , Quemaduras/etiología , Adulto , Superficie Corporal , Unidades de Quemados/organización & administración , Unidades de Quemados/estadística & datos numéricos , Quemaduras/epidemiología , Femenino , Gasolina/efectos adversos , Gasolina/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
2.
J Environ Sci (China) ; 59: 24-29, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28888235

RESUMEN

The status of energy consumption and air pollution in China is serious. It is important to analyze and predict the different fuel consumption of various types of vehicles under different influence factors. In order to fully describe the relationship between fuel consumption and the impact factors, massive amounts of floating vehicle data were used. The fuel consumption pattern and congestion pattern based on large samples of historical floating vehicle data were explored, drivers' information and vehicles' parameters from different group classification were probed, and the average velocity and average fuel consumption in the temporal dimension and spatial dimension were analyzed respectively. The fuel consumption forecasting model was established by using a Back Propagation Neural Network. Part of the sample set was used to train the forecasting model and the remaining part of the sample set was used as input to the forecasting model.


Asunto(s)
Automóviles/estadística & datos numéricos , Gasolina/estadística & datos numéricos , Emisiones de Vehículos/análisis , China , Monitoreo del Ambiente , Predicción , Redes Neurales de la Computación
3.
Curr Obes Rep ; 6(1): 3-9, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28243840

RESUMEN

PURPOSE OF REVIEW: Traveling by automobile rather than walking or cycling can encourage obesity by eliminating physical activity. As national obesity rates in the USA have reached 37.9% in 2014, understanding the connections between obesity and transportation choices can help policymakers in the public health community propose effective obesity interventions at the national level. RECENT FINDINGS: Following from foundational studies examining associations between the built environment and leisure walking, recent studies consider a diverse set of transportation choices regarding mode (e.g., automobile, walking, public transit) and purpose (e.g., commuting, leisure), along with studies on the effectiveness of several transportation-related interventions for obesity. The reviewed studies point toward potential interventions for obesity; there is emerging evidence that commuting by public transit may be one such intervention. Moreover, new data-gathering tools such as global positioning systems, geographic information systems, and accelerometers may alleviate statistical obstacles in conducting future studies.


Asunto(s)
Conducción de Automóvil/psicología , Obesidad/etiología , Transportes , Adulto , Ciclismo/fisiología , Ciclismo/psicología , Planificación Ambiental , Ejercicio Físico/fisiología , Ejercicio Físico/psicología , Gasolina/estadística & datos numéricos , Humanos , Actividades Recreativas/psicología , Caminata/fisiología , Caminata/psicología , Lugar de Trabajo/psicología
6.
Am J Respir Crit Care Med ; 191(12): 1413-21, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25867003

RESUMEN

RATIONALE: More than 25 million American children breathe polluted air on diesel school buses. Emission reduction policies exist, but the health impacts to individual children have not been evaluated. METHODS: Using a natural experiment, we characterized the exposures and health of 275 school bus riders before, during, and after the adoption of clean technologies and fuels between 2005 and 2009. Air pollution was measured during 597 trips on 188 school buses. Repeated measures of exhaled nitric oxide (FeNO), lung function (FEV1, FVC), and absenteeism were also collected monthly (1,768 visits). Mixed-effects models longitudinally related the adoption of diesel oxidation catalysts (DOCs), closed crankcase ventilation systems (CCVs), ultralow-sulfur diesel (ULSD), or biodiesel with exposures and health. MEASUREMENTS AND MAIN RESULTS: Fine and ultrafine particle concentrations were 10-50% lower on buses using ULSD, DOCs, and/or CCVs. ULSD adoption was also associated with reduced FeNO (-16% [95% confidence interval (CI), -21 to -10%]), greater changes in FVC and FEV1 (0.02 [95% CI, 0.003 to 0.05] and 0.01 [95% CI, -0.006 to 0.03] L/yr, respectively), and lower absenteeism (-8% [95% CI, -16.0 to -0.7%]), with stronger associations among patients with asthma. DOCs, and to a lesser extent CCVs, also were associated with improved FeNO, FVC growth, and absenteeism, but these findings were primarily restricted to patients with persistent asthma and were often sensitive to control for ULSD. No health benefits were noted for biodiesel. Extrapolating to the U.S. population, changed fuel/technologies likely reduced absenteeism by more than 14 million/yr. CONCLUSIONS: National and local diesel policies appear to have reduced children's exposures and improved health.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/prevención & control , Gasolina/estadística & datos numéricos , Estado de Salud , Vehículos a Motor/estadística & datos numéricos , Emisiones de Vehículos/prevención & control , Absentismo , Biocombustibles/estadística & datos numéricos , Niño , Monitoreo del Ambiente/estadística & datos numéricos , Femenino , Humanos , Estudios Longitudinales , Masculino , Óxido Nítrico/metabolismo , Pruebas de Función Respiratoria/estadística & datos numéricos , Washingtón
7.
J Hazard Mater ; 287: 151-61, 2015 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25644031

RESUMEN

To reduce greenhouse gas emissions, which contribute to global warming, production of gasoline blended with ethyl tert-buthyl ether (ETBE) is increasing annually. The flash point of ETBE is higher than that of gasoline, and blending ETBE into gasoline will change the flash point and the vapor pressure. Therefore, it is expected that the fire hazard caused by ETBE-blended gasoline would differ from that caused by normal gasoline. The aim of this study was to acquire the knowledge required for estimating the fire hazard of ETBE-blended gasoline. Supposing that ETBE-blended gasoline was a two-component mixture of gasoline and ETBE, we developed a prediction model that describes the vapor pressure and flash point of ETBE-blended gasoline in an arbitrary ETBE blending ratio. We chose 8-component hydrocarbon mixture as a model gasoline, and defined the relation between molar mass of gasoline and mass loss fraction. We measured the changes in the vapor pressure and flash point of gasoline by blending ETBE and evaporation, and compared the predicted values with the measured values in order to verify the prediction model. The calculated values of vapor pressures and flash points corresponded well to the measured values. Thus, we confirmed that the change in the evaporation characteristics of ETBE-blended gasoline by evaporation could be predicted by the proposed model. Furthermore, the vapor pressure constants of ETBE-blended gasoline were obtained by the model, and then the distillation curves were developed.


Asunto(s)
Éteres de Etila/química , Gasolina/estadística & datos numéricos , Pentanos/química , Tolueno/química , Volatilización
9.
Asian Pac J Cancer Prev ; 15(7): 2959-64, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24815431

RESUMEN

While several reproductive and lifestyle-related factors are already well-known as established risk factors for breast cancer, environmental factors have attracted attention only recently. The objective of the current study was to assess the association between the breast cancer incidences in females, the mortality rate and the number of motor vehicles on the one side and the consumption of gasoline which could work as a major source of air pollution at the other side. The breast cancer incidences and the mortality trends were compared with various indices of westernization like dietary patterns or industrialization with 10 years lag of time. Geographical variations with 10, 15 and 20 years lag of time were assessed between the breast cancer incidence in 2010 and the number of motor vehicles as well as the consumption of gasoline. The upward trend of motor vehicle numbers proved to be comparable to those of breast cancer incidence and mortality. However, the consumption of gasoline started to decrease since the mid-1990s. The geographic distribution of motor vehicle numbers and gasoline consumption in 1990 is in a positive correlation with the breast cancer incidence rates in 2010 and the 20-year lag time (R2 0.379 with the number of motor vehicles and 0.345 with consumption of gasoline). In a linear relationship between the breast cancer incidences in 2010 and the log transformed number of motor vehicles, the log transformed consumption of gasoline in 2000 also showed a positive relationship (R2 0.367 with the number of motor vehicles and 0.329 with consumption of gasoline). The results of the current study indicate that there may be a positive relation between the number of vehicles, gasoline consumption and the incidence of breast cancer from the aspects of long-term trends and geographical variation.


Asunto(s)
Neoplasias de la Mama/epidemiología , Exposición a Riesgos Ambientales , Gasolina/estadística & datos numéricos , Vehículos a Motor/estadística & datos numéricos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/economía , Neoplasias de la Mama/mortalidad , Femenino , Gasolina/economía , Humanos , República de Corea/epidemiología , Factores de Riesgo
10.
Environ Int ; 51: 45-58, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23160083

RESUMEN

Transportation policy measures often aim to change travel behaviour towards more efficient transport. While these policy measures do not necessarily target health, these could have an indirect health effect. We evaluate the health impact of a policy resulting in an increase of car fuel prices by 20% on active travel, outdoor air pollution and risk of road traffic injury. An integrated modelling chain is proposed to evaluate the health impact of this policy measure. An activity-based transport model estimated movements of people, providing whereabouts and travelled kilometres. An emission- and dispersion model provided air quality levels (elemental carbon) and a road safety model provided the number of fatal and non-fatal traffic victims. We used kilometres travelled while walking or cycling to estimate the time in active travel. Differences in health effects between the current and fuel price scenario were expressed in Disability Adjusted Life Years (DALY). A 20% fuel price increase leads to an overall gain of 1650 (1010-2330) DALY. Prevented deaths lead to a total of 1450 (890-2040) Years Life Gained (YLG), with better air quality accounting for 530 (180-880) YLG, fewer road traffic injuries for 750 (590-910) YLG and active travel for 170 (120-250) YLG. Concerning morbidity, mostly road safety led to 200 (120-290) fewer Years Lived with Disability (YLD), while air quality improvement only had a minor effect on cardiovascular hospital admissions. Air quality improvement and increased active travel mainly had an impact at older age, while traffic safety mainly affected younger and middle-aged people. This modelling approach illustrates the feasibility of a comprehensive health impact assessment of changes in travel behaviour. Our results suggest that more is needed than a policy rising car fuel prices by 20% to achieve substantial health gains. While the activity-based model gives an answer on what the effect of a proposed policy is, the focus on health may make policy integration more tangible. The model can therefore add to identifying win-win situations for both transport and health.


Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Gasolina/economía , Evaluación del Impacto en la Salud , Política de Salud , Transportes/economía , Viaje/economía , Adolescente , Adulto , Contaminación del Aire/prevención & control , Política Ambiental , Femenino , Gasolina/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Morbilidad , Medición de Riesgo , Impuestos , Transportes/estadística & datos numéricos , Viaje/psicología , Viaje/estadística & datos numéricos , Caminata/estadística & datos numéricos , Adulto Joven
11.
J Environ Monit ; 14(11): 2893-901, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23032582

RESUMEN

Analyses of lead (Pb) isotopes have been performed in terrestrial and fresh water environments to estimate historical uses of leaded fuel, but so far this method has not been employed in studies of world-wide marine surface sediments. We analyzed Pb and its isotopes in 23 surface sediments from four continents collected during the Galathea 3 expedition in 2006-2007. To enhance the anthropogenic signal, a partial digestion using nitric acid was performed. The concentrations of Pb, Th, U and Al were determined with an ICP-Quadrupole MS, and Pb-isotope ratios with an ICP-multi-collector MS. The samples could be divided into three groups: Harbor areas in larger cities with concentrations of 150 to 265 mg kg(-1) dry weight, smaller towns with concentrations between 20 and 40 mg kg(-1) dry weight, and remotely located sites with concentrations below 15 mg kg(-1) dry weight. Pb-isotope ratios were compared to literature values for gasoline and local or geological background values, and the contribution of leaded-gasoline to total concentrations was calculated for contaminated sites using both a one-dimensional and a novel two-dimensional (vector) method. The North American sites had Pb-isotope ratios corresponding to the US leaded gasoline, with 24-88% of the Pb from leaded gasoline. Samples from Oceania showed Pb-isotope ratios corresponding to Australian gasoline, with 60% attributed to leaded gasoline in Sydney and 21% in Christchurch. Outside Cape Town, 15 to 46% of Pb in sediments was from leaded gasoline.


Asunto(s)
Monitoreo del Ambiente/métodos , Gasolina/estadística & datos numéricos , Sedimentos Geológicos/química , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Isótopos/análisis
12.
Environ Sci Technol ; 46(20): 11408-17, 2012 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-22906224

RESUMEN

The environmental health impacts of transportation depend in part on where and when emissions occur during fuel production and combustion. Here we describe spatially and temporally explicit life cycle inventories (LCI) of air pollutants from gasoline, ethanol derived from corn grain, and ethanol from corn stover. Previous modeling for the U.S. by Argonne National Laboratory (GREET: Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) suggested that life cycle emissions are generally higher for ethanol from corn grain or corn stover than for gasoline. Our results show that for ethanol, emissions are concentrated in the Midwestern "Corn Belt". We find that life cycle emissions from ethanol exhibit different temporal patterns than from gasoline, reflecting seasonal aspects of farming activities. Enhanced chemical speciation beyond current GREET model capabilities is also described. Life cycle fine particulate matter emissions are higher for ethanol from corn grain than for ethanol from corn stover; for black carbon, the reverse holds. Overall, our results add to existing state-of-the-science transportation fuel LCI by providing spatial and temporal disaggregation and enhanced chemical speciation, thereby offering greater understanding of the impacts of transportation fuels on human health and opening the door to advanced air dispersion modeling of fuel life cycles.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Etanol/análisis , Gasolina/análisis , Emisiones de Vehículos/análisis , Ambiente , Monitoreo del Ambiente , Gasolina/estadística & datos numéricos , Humanos , Modelos Químicos , Análisis Espacial , Estados Unidos , Zea mays
13.
Environ Res ; 111(4): 597-602, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21453914

RESUMEN

OBJECTIVES: To assess the temporal and spatial relationship of risk for total leukemia and AML (acute myelogenous leukemia) among community residents of an area in northeastern (NE) Pennsylvania (PA) affected by the Tranguch Gasoline Spill which occurred in the early 1990s. METHODS: Standardized incidence ratios (SIR) were calculated for total leukemia and AML among 625 residents affected by the gasoline spill in relation to both PA and local county cancer incidence rates. The risk of total leukemia and AML among the gasoline exposed population was evaluated for the period prior to the spill, 1985-1989; during the time surrounding the spill, 1990-1994; and for a period subsequent to the spill, 1995-2001. RESULTS: The incidence of total leukemia and AML was significantly elevated subsequent to the spill for the entire period 1990-2001 and was highest for the period 1995-2001, whether comparison was made to PA or local county leukemia rates. Based on comparison to PA rates, the SIRs for total leukemia and AML were 7.69 (95% CI=1.58-22.46) and 11.54 (95% CI=2.38-33.69) for the 1995-2001 period, respectively. Prior to the spill, 1985-1989, and during the period of the spill, 1990-1994, no cases of leukemia were identified among the affected residents. CONCLUSIONS: These results suggest a possible association between chronic low level benzene exposure and increased risk of leukemia among residents of the Tranguch Spill Site in NE PA. Our study provides additional support to the growing body of evidence implicating low level benzene exposure and cancer risk. We recommend that other communities contaminated with gasoline vapor through leaking underground storage vessels be monitored for elevated risk of leukemia.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Gasolina/análisis , Leucemia/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Contaminantes Atmosféricos/toxicidad , Liberación de Peligros Químicos , Exposición a Riesgos Ambientales/análisis , Femenino , Estudios de Seguimiento , Gasolina/estadística & datos numéricos , Gasolina/toxicidad , Humanos , Masculino , Persona de Mediana Edad , Pennsylvania/epidemiología , Medición de Riesgo , Adulto Joven
14.
JEMS ; 36(4): 16, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21481674
15.
Environ Sci Technol ; 45(6): 2406-12, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21322628

RESUMEN

Auto-rickshaws in India use different fuels and engine technologies, with varying emissions and implications for air quality and climate change. Chassis dynamometer emission testing was conducted on 30 in-use auto-rickshaws to quantify the impact of switching from gasoline to compressed natural gas (CNG) in spark-ignition engines. Thirteen test vehicles had two-stroke CNG engines (CNG-2S) and 17 had four-stroke CNG engines (CNG-4S), of which 11 were dual-fuel and operable on a back-up gasoline (petrol) system (PET-4S). Fuel-based emission factors were determined for gaseous pollutants (CO(2), CH(4), NO(X), THC, and CO) and fine particulate matter (PM(2.5)). Intervehicle variability was high, and for most pollutants there was no significant difference (95% confidence level) between "old" (1998-2001) and "new" (2007-2009) age-groups within a given fuel-technology class. Mean fuel-based PM(2.5) emission factor (mean (95% confidence interval)) for CNG-2S (14.2 g kg(-1) (6.2-26.7)) was almost 30 times higher than for CNG-4S (0.5 g kg(-1) (0.3-0.9)) and 12 times higher than for PET-4S (1.2 g kg(-1) (0.8-1.7)). Global warming commitment associated with emissions from CNG-2S was more than twice that from CNG-4S or PET-4S, due mostly to CH(4) emissions. Comprehensive measurements and data should drive policy interventions rather than assumptions about the impacts of clean fuels.


Asunto(s)
Contaminantes Atmosféricos/análisis , Combustibles Fósiles/estadística & datos numéricos , Vehículos a Motor/estadística & datos numéricos , Emisiones de Vehículos/análisis , Cambio Climático , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Combustibles Fósiles/análisis , Gasolina/análisis , Gasolina/estadística & datos numéricos , Calentamiento Global , Humanos , India , Material Particulado/análisis
16.
Environ Sci Technol ; 45(1): 147-53, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-20690777

RESUMEN

Beijing, the capital of China, has experienced rapid motorization since 1990; a trend that is likely to continue. The growth in vehicles and the corresponding emissions create challenges to improving the urban air quality. In an effort to reduce the impact of vehicle emissions on urban air quality, Beijing has adopted a number of vehicle emission control strategies and policies since the mid 1990 s. These are classified into seven categories: (1) emission control on new vehicles; (2) emission control on in-use vehicles; (3) fuel quality improvements; (4) alternative-fuel and advanced vehicles; (5) economic policies; (6) public transport; and (7) temporal traffic control measures. Many have proven to be successful, such as the Euro emission standards, unleaded gasoline and low sulfur fuel, temporal traffic control measures during the Beijing Olympic Games, etc. Some, however, have been failures, such as the gasoline-to-LPG taxi retrofit program. Thanks to the emission standards for new vehicles as well as other controls, the fleet-average emission rates of CO, HC, NO(X), and PM(10) by each major vehicle category are decreasing over time. For example, gasoline cars decreased fleet-average emission factors by 12.5% for CO, 10.0% for HC, 5.8% for NO(X), and 13.0% for PM(10) annually since 1995, and such a trend is likely to continue. Total emissions for Beijing's vehicle fleet increased from 1995 to 1998. However, they show a clear and steady decrease between 1999 and 2009. In 2009, total emissions of CO, HC, NO(X), and PM(10) were 845,000 t, 121,000 t, 84,000 t, and 3700 t, respectively; with reductions of 47%, 49%, 47%, and 42%, relative to 1998. Beijing has been considered a pioneer in controlling vehicle emissions within China, similar to the role of California to the U.S. The continued rapid growth of vehicles, however, is challenging Beijing's policy-makers.


Asunto(s)
Contaminación del Aire/prevención & control , Emisiones de Vehículos/prevención & control , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , China , Ciudades , Política Ambiental , Predicción , Gasolina/estadística & datos numéricos , Vehículos a Motor/estadística & datos numéricos , Mejoramiento de la Calidad , Emisiones de Vehículos/análisis , Emisiones de Vehículos/legislación & jurisprudencia
17.
Prehosp Disaster Med ; 26(5): 394-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22336185

RESUMEN

INTRODUCTION: Emergency medical services (EMS) systems are a central component of the healthcare system, particularly for older patients. As currently configured, EMS transport is fundamentally petroleum dependent. Petroleum scarcity is an emerging public health concern, particularly for patient transport. Little is known regarding EMS fuel use, potential impacts of scarcity on operations, or strategies to minimize these impacts. OBJECTIVE: The objective of this study was to characterize the fuel use of a large, urban, hospital-based, dynamically-deployed EMS system, and to identify broad optimization categories to minimize EMS's petroleum dependence. METHODS: Fuel use was reviewed retrospectively using fuel purchasing and maintenance data from January 2007 through September 2008. Data on unit-hours, call volume, and patient transports also were collected. Data were processed using descriptive statistics. RESULTS: During the study period, a fleet of 35 diesel ambulances operated for 277,849 unit-hours and traveled 1,902,710 miles. Detailed mileage data were available for 66,527 unit-hours, 23.9% of the sample. Overall, vehicles averaged 6.6.89 (6.71, 7.08) miles per gallon (mpg), 11.5 (10.4, 12.6) miles were travelled per call, and 16.2 (14.8, 17.6) miles per transport; 2.7 (2.4, 2.9) gallons of fuel were used per transport. CONCLUSIONS: In this EMS system, operations are fundamentally dependent on petroleum. Mileage estimates can serve as a baseline to evaluate interventions for reducing petroleum dependence and in contingency planning. As cost pressures increase and these interventions become more common, systematic evaluations will be important.


Asunto(s)
Ambulancias , Sistemas de Comunicación entre Servicios de Urgencia/estadística & datos numéricos , Anciano , Gasolina/estadística & datos numéricos , Georgia , Servicios de Salud para Ancianos , Humanos , Estudios Retrospectivos
18.
J Air Waste Manag Assoc ; 59(11): 1339-46, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19947115

RESUMEN

This study investigated the emissions of criteria air pollutants (carbon monoxide [CO], hydrocarbons [HCs], and oxides of nitrogen [NOx]) from motorcycle exhaust at cold- and hot-start driving cycles on a chassis dynamometer. Seven four-stroke carburetors and two fuel-injection motorcycles were tested. As expected, the emission factors (g/km) of CO and HCs increased during cold-start driving. The ratio of emission factors (g/km) for cold- and hot-start driving cycles ranged from 1.1-1.5 (for CO) to 1.2-2.8 (for HCs). However, the difference of NOx emissions between the cold- and hot-start cycles was not pronounced. Further, the cold-/hot-start ratios of CO and HCs from 50-cm3 motorcycles were higher than those of 100- and 125-cm3 motorcycles; however, the carbon dioxide (CO2) emission was the lowest for the four-stroke motorcycles. High engine temperature and poor combustion efficiency of smaller cylinder-capacity motorcycles may contribute a significant amount of exhaust emission. Additionally, the fuel-base emission factor (g/L-fuel) ratios were low compared with the distance-base emission factor (g/km) in cold- and hot-start driving. This indicates that the effect of catalyst efficiency was greater than the effect of fuel combustion in the tested motorcycles. A comparison of emission ratios of motorcycles and passenger cars shows that the warm-up may be more important for cars, especially under low-temperature conditions. However, the motorcycle contributes a large proportion of CO and HC emissions in many Asian counties. The difference between cold- and hot-start emissions may affect inventory


Asunto(s)
Contaminantes Atmosféricos/análisis , Motocicletas , Emisiones de Vehículos/análisis , Frío , Gasolina/estadística & datos numéricos , Calor
19.
Int J Epidemiol ; 38(4): 1137-40, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19377099

RESUMEN

BACKGROUND: The increasing global prevalence of overweight and obesity has serious implications for the environment, as well as for health. We estimate the impact on greenhouse gas emissions of increases in the population distribution of body mass index (BMI). METHODS: We estimated the food energy required to maintain basal metabolic rate in two hypothetical adult populations using the Schofield equations for males and females. Additional greenhouse gas emissions due to higher fuel energy use for transporting a heavier population were estimated. RESULTS: Compared with a normal population distribution of BMI, a population with 40% obese requires 19% more food energy for its total energy expenditure. Greenhouse gas emissions from food production and car travel due to increases in adiposity in a population of 1 billion are estimated to be between 0.4 Giga tonnes (GT) and 1.0 GT of carbon dioxide equivalents per year. CONCLUSIONS: The maintenance of a healthy BMI has important environmental benefits in terms of lower greenhouse gas emissions.


Asunto(s)
Adiposidad/fisiología , Efecto Invernadero , Sobrepeso/epidemiología , Adulto , Conducción de Automóvil/estadística & datos numéricos , Índice de Masa Corporal , Ingestión de Alimentos/fisiología , Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Abastecimiento de Alimentos , Gasolina/estadística & datos numéricos , Humanos , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/fisiopatología , Sobrepeso/fisiopatología
20.
Bioresour Technol ; 99(8): 3244-50, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17697777

RESUMEN

A preliminary evaluation of the feasibility of producing biodiesel using oil extracted from defective coffee beans was conducted as an alternative means of utilizing these beans instead of roasting for consumption of beverage with depreciated quality. Direct transesterifications of triglycerides from refined soybean oil (reference) and from oils extracted from healthy and defective coffee beans were performed. Type of alcohol employed and time were the reaction parameters studied. Sodium methoxide was used as alkaline catalyst. There was optimal phase separation after reactions using both soybean and healthy coffee beans oils when methanol was used. This was not observed when using the oil from defective beans which required further processing to obtain purified alkyl esters. Nevertheless, coffee oil was demonstrated to be a potential feedstock for biodiesel production, both from healthy and defective beans, since the corresponding oils were successfully converted to fatty acid methyl and ethyl esters.


Asunto(s)
Alimentación Animal , Café , Gasolina , Aceites de Plantas , Café/normas , Ésteres/análisis , Etanol , Ácidos Grasos/análisis , Gasolina/estadística & datos numéricos , Cinética , Metanol , Glycine max
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