Local and NON-LOCAL source apportionment of black carbon and combustion generated PM2.5.

Current methods for measuring black carbon aerosol (BC) by optical methods apportion BC to fossil fuel and wood combustion. However, these results are aggregated: local and non-local combustion sources are lumped together. The spatial apportioning of carbonaceous aerosol sources is challenging in remote or suburban areas because non-local sources may be significant. Air quality modeling would require highly accurate emission inventories and unbiased dispersion models to quantify such apportionment. We propose FUSTA (FUzzy SpatioTemporal Apportionment) methodology for analyzing aethalometer results for equivalent black carbon coming from fossil fuel (eBCff) and wood combustion (eBCwb). We applied this methodology to ambient measurements at three suburban sites around Santiago, Chile, in the winter season 2021. FUSTA results showed that local sources contributed ∼80% to eBCff and eBCwb in all sites. By using PM2.5 - eBCff and PM2.5 - eBCwb scatterplots for each fuzzy cluster (or source) found by FUSTA, the estimated lower edge lines showed distinctive slopes in each measurement site. These slopes were larger for non-local sources (aged aerosols) than for local ones (fresh emissions) and were used to apportion combustion PM2.5 in each site. In sites Colina, Melipilla and San Jose de Maipo, fossil fuel combustion contributions to PM2.5 were 26 % (15.9 µg m-3), 22 % (9.9 µg m-3), and 22 % (7.8 µg m-3), respectively. Wood burning contributions to PM2.5 were 22 % (13.4 µg m-3), 19 % (8.9 µg m-3) and 22% (7.3 µg m-3), respectively. This methodology generates a joint source apportionment of eBC and PM2.5, which is consistent with available chemical speciation data for PM2.5 in Santiago.

Organic-resistant screen-printed graphitic electrodes: Application to on-site monitoring of liquid fuels.

This work presents the potential application of organic-resistant screen-printed graphitic electrodes (SPGEs) for fuel analysis. The required analysis of the antioxidant 2,6-di-tert-butylphenol (2,6-DTBP) in biodiesel and jet fuel is demonstrated as a proof-of-concept. The screen-printing of graphite, Ag/AgCl and insulator inks on a polyester substrate (250 µm thickness) resulted in SPGEs highly compatible with liquid fuels. SPGEs were placed on a batch-injection analysis (BIA) cell, which was filled with a hydroethanolic solution containing 99% v/v ethanol and 0.1 mol L(-1) HClO4 (electrolyte). An electronic micropipette was connected to the cell to perform injections (100 µL) of sample or standard solutions. Over 200 injections can be injected continuously without replacing electrolyte and SPGE strip. Amperometric detection (+1.1 V vs. Ag/AgCl) of 2,6-DTBP provided fast (around 8 s) and precise (RSD = 0.7%, n = 12) determinations using an external calibration curve. The method was applied for the analysis of biodiesel and aviation jet fuel samples and comparable results with liquid and gas chromatographic analyses, typically required for biodiesel and jet fuel samples, were obtained. Hence, these SPGE strips are completely compatible with organic samples and their combination with the BIA cell shows great promise for routine and portable analysis of fuels and other organic liquid samples without requiring sophisticated sample treatments.

Tendências na literatura científica global sobre o biodiesel: uma análise cienciométrica / Trends in global scientific literature about biodiesel: a scientometrics analysis

O combustível fóssil dá sinais de esgotamento das suas reservas além de afetar o meio ambiente devido à poluição decorrente de sua queima. Surgiu assim um novo desafio: encontrar um combustível substituto que seja renovável e que seja menos poluente. O biodiesel surgiu como potencial substituto do combustível fóssil, por ser oriundo de várias matérias primas, reduzir o impacto ambiental gerado por poluição e ainda trazer vários benefícios sociais. Porém essa tecnologia é nova e ainda precisa ser aperfeiçoada. Vários trabalhos científicos vêm surgindo com o intuito de trazer melhoria para o biodiesel. Por meio da Cienciometria é possível saber a tendência de pesquisa desses trabalhos, sendo este fato importante para a sociedade acadêmica, para que possam ser realizados novos estudos de biodiesel. Sendo assim, objetivou-se neste trabalho fazer uma análise cienciométrica do biodiesel. O banco de dados utilizado foi o "SciVerseScopus". Foi realizada uma busca de todos os trabalhos que possuía no título a palavra biodiesel*. Os trabalhos foram analisados a partir de 1993, primeiro ano de registro para o termo, até 2010. As seguintes informações foram levantadas: a)Ano de publicação, b)Tipo de trabalho, c)Tipo do periódico em que o trabalho foi publicado, d)Nome do periódico em que o trabalho foi publicado, e)Área de concentração, f)Palavras-chave, g)Idioma, h)País de publicação, e i)Matéria prima utilizada para a obtenção do biodiesel estudado em trabalhos brasileiros. De uma forma geral os trabalhos analisados acompanham as tendências mundiais de produção e consumo do biodiesel, mostrando-se importantes para o aperfeiçoamento desta tecnologia.

Fossil fuel is showing signs of depletion of its reserves and affect the environment due to pollution from burning. Thus emerged a new challenge: to find a substitute fuel that is renewable and less polluting. Biodiesel has emerged as a potential substitute for fossil fuel, for it comes from various raw materials, reduce the environmental impact of pollution and also bring many benefits. However this technology is new and still needs to be improved. Several scientific studies have emerged in order to bring about improvement for biodiesel. Through scientometrics is possible to know the trend of research work, which is indeed important for the academic society, that may be new studies of biodiesel. Thus, this study aimed to make a scientometric analysis of biodiesel. The database used was the "SciVerseScopus." We performed a search of all studies that had biodiesel* in the title. The studies were analyzed from 1993, the first year of registration for the term until 2010. The following information was obtained: a) Year of publication, b) type of study, c) Type of the journal where the paper was published, d) name of journal in which the study was published, e) Area of concentration, f) keywords, g) Language, h) Country of publication, i) Raw materials used to obtain biodiesel studied in Brazilian studies. In general the studies analyzed follow world trends in production and consumption of biodiesel, being important for the improvement of technology. New jobs scientometrics of biodiesel can be made taking into account their specific characteristics.

Contaminación del aire de interiores en hogares en situación de pobreza extrema en Colombia / Indoor air pollution in extremely poor Colombian households

Objetivo Caracterizar la exposición a la contaminación del aire interior por uso de combustibles sólidos en hogares en situación de pobreza extrema en Colombia. Métodos A partir de la información gubernamental oficial de hogares en situación de pobreza extrema (encuesta Red Unidos de septiembre 2012, n=1,3 millones de hogares y >5 millones de individuos) se estructuraron dos modelos de regresión logística: (i) Factores asociados al uso de combustibles sólidos para cocinar a nivel hogar, (ii) Asociación entre el uso de combustibles sólidos en el hogar y prevalencia de limitaciones de la salud a nivel individuo. Resultados Un total de 530 mil hogares en situación de pobreza extrema donde habitan 2,1 millones de colombianos, enfrentan el factor de riesgo (uso de combustibles fósiles en el hogar). La presencia del factor de riesgo está asociada a la zona rural (odds ratio-OR=19,4; intervalo de confianza al 95 %-IC95 %: 19,2-19,6), la etnia indígena (OR=2,9; IC95 %:2,9-3,0) y, de manera inversa, a la situación de desplazamiento (OR=0,6;IC95 %:0,6-0,6). La prevalencia de limitación cardiovascular y/o respiratoria, así como de limitación en visión se asociaron con la exposición. Discusión Las iniciativas que busquen mejorar la salud ambiental y calidad de vida de la población rural de mayor vulnerabilidad socio-económica del país cuentan con información de caracterización e impacto para priorizar programas tendientes a disminuir la exposición al uso de combustibles sólidos.

Objective Characterising exposure to indoor air pollution arising from solid-fuel use in extremely poor Colombian households. Methods Data from the September 2012 survey by Red Unidos (literally United Network, the Colombian government's official instrument for identifying extremely poor households: n=1.3 million households and >5 million people) was used for two logistic regression models: factors associated with solid fuel used in cooking within households and an association between exposure to solid fuel use in households and the prevalence of limitations regarding individual health. Results According to the Red Unidos data-based models, 2.1 million people living in 530,000 extremely poor households were exposed to environmental health risk (i.e. household air pollution caused by solid fuel use). Such risk was found to be related to living in rural areas (odds ratio (OR)=19.4 95 % confidence interval (95 %CI): 19.2-19.6 %), having an Indian background (OR=2.9: 2.9-3.0 95 %CI) and, inversely (i.e. when living in towns), internal displacement (OR=0.6: 0.6-0.695 %CI). The prevalence of permanent cardiovascular and respiratory limitations and limited vision were associated with exposure to indoor air pollution arising from solid fuel use. Discussion Initiatives for improving environmental health and the quality of life for extremely poor rural households in Colombia must make full use of the available characterisation data and its impact for prioritising programmes aimed at reducing exposure to solid fuel use.

HUELLA DE CARBONO EN CADENAS PRODUCTIVAS DE CAFÉ (Coffea arabica L) CON DIFERENTES ESTÁNDARES DE CERTIFICACIÓN EN COSTA RICA / CARBON FOOTPRINTS IN THE COFFEE (Coffea arabica L) PRODUCTIVE CHAINS WITH DIFFERENT CERTIFICATION STANDARDS IN COSTA RICA

Se estudió el impacto en la producción de café con diferentes estándares de certificación (producción convencional, producción orgánica -NOP y Unión Europea-, UTZ Kapeh, Comercio Justo, Rainforest Alliance y CAFE Practices) sobre la huella de carbono en Costa Rica. Las emisiones de gases de efecto invernadero (GEI) se estimaron en nueve fincas y ocho empresas procesadoras del grano. Se estimó la fijación de carbono en biomasa total, en árboles de sombra y cafetos, midiendo las plantas, empleando modelos de biomasa y factores de expansión de biomasa, una fracción de carbono de 0,5 e indagando a productores sobre la edad de los componentes del sistema. Se emplearon factores de emisión recomendados por el IPCC (Intergovernmental Panel on Climate Change). Los sistemas de producción fijaron entre 5,0 y 17,6 t CO2e/ha/año, sin un efecto de los estándares de certificación. La actividad que más emite GEI fue la fertilización nitrogenada (63-82% del total de emisiones). Las dos procesadoras con menor emisión de GEI (156 y 187 kg CO2e/t café verde) son aquellas que emplean la energía solar para secar parcialmente el café. La cadena de producción de café en Costa Rica mostró ser amigable con el medio ambiente, al fijar netamente entre 2,4 y 13,0 kg CO2e/kg de grano de café verde (en promedio 7,6 kg CO2e/kg de café verde y 8,1 t CO2e/ha/año). No se encontró impacto de los estándares de certificación pero si de los componentes del sistema en la huella de carbono en la cadena de producción de café.

The impact in coffee production with different certification standards (conventional production, organic production -NOP and European Union-, UTZ Kapeh, Fairtrade, Rainforest Alliance and CAFE Practices) on Carbon Footprint in Costa Rica was studied. The greenhouse gas emissions (GHG) were estimated in nine farms and eight grain processing industries. Carbon fixation was estimated in total biomass in both shade trees and coffee bushes by measuring the plants, using biomass models and biomass expansion factors, a 0.5 fraction of carbon and asking producers about the age of the components in the system. IPCC (Intergovernmental Panel on Climate Change) recommended emission factors were used. The production systems fixed between 5,0 and 17,6 t CO2e/ha/year, without an effect of the certification standards. The activity emitting more GHG was nitrogenated fertilization (63-82% of total emissions). The two grain processing industries with less GEE emissions (156 and 187 CO2e/t green coffee) are those using solar energy for partial coffee drying. The coffee production chain in Costa Rica showed to be friendly with the environment while fixing a net between 2.4 and 13.0 kg CO2e/kg of green coffee grain (7.6 kg CO2e/kg of green coffee average and 8.1 t CO2e/ha/year). Impact on the certification standards was not found but it was found in the system components of the carbon footprint in the coffee production chain.

The cost of connecting poor households to natural gas in Colombia and its impact on health, 2007 / Impacto en la salud y el costo de conexión de gas natural domiciliario en los hogares pobres en Colombia, 2007

Objective Assessing the cost of subsidizing access to household natural gas (HNG) and its impact on the health of about 35,000 poor households (socioeconomic strata 1 and 2) in Colombia, sponsored by a Global Partnership on Output-Based Aid (GPOBA) project. Methods The following studies were combined: an analysis of secondary data and analysis of databases provided by the Promigas foundation, demographic data from the 2005 DANE census and databases regarding Central Bank economic statistical series; an analysis of the burden of disease estimated from parameters identified in previous studies; an analysis of the cost of the burden of illness and the estimated costs which were avoided by implementing the HNG connections program; and an analysis of the cost effectiveness of the program linking homes to HNG services. Results The OBA project led to about 4,000 to 5,000 cases of acute respiratory disease (ARD) and 1,200 to 2,300 outpatient cases of chronic obstructive pulmonary disease (COPD) being avoided during the study period; around 1,200 hospitalizations due to ARD and 500 due to COPD were also avoided. Forty-five to 170 deaths (representing about 45,000 to 90,000 disability-adjusted life years (DALY)) were also avoided. The economic cost of the burden of disease arising from ARI and COPD in such scenario without HNG would have been between 10.7 and 23.6 million dollars, whilst HNG led to costs becoming reduced by about 32 %. Conclusions This study was a good estimator of the potential impact of the poorest and most vulnerable households gaining universal access to HNG.

Objetivo Valorar el impacto sanitario y económico de subsidiar el acceso al Gas Natural Domiciliario (GND) a hogares pobres (estratos socioeconómicos 1 y 2) en Colombia, auspiciado por Global Partnership on Output Based Aid (GPOBA), proyecto OBA. Métodos Se combinaron los siguientes estudios: a) Análisis de bases de datos secundarios tomadas de Fundación Promigas, censo DANE 2005, y series estadísticas del Banco de la República b) Análisis de carga de enfermedad estimada a partir de los parámetros de estudios previos c) Análisis de costos de la carga de enfermedad estimada y de los costos evitados luego de implementado el programa de conexiones de GND d) Análisis de costo efectividad del programa de conexiones de los hogares al servicios de GND. Resultados La presencia del proyecto OBA evitaría, durante el periodo de estudio, cerca de 4 mil y 5 mil casos ambulatorio de IRA y entre 1 200 y 2 300 de EPOC. Además, se evitarían cerca de 1200 hospitalizaciones por IRA y cerca de 500 por EPOC. Igualmente se evitaría entre 45 y 170 muertes que representaría cerca de 45 mil a 90 mil AVAD. Los costos económicos de la carga de enfermedad por IRA y EPOC en el escenario sin GND serían entre 10,7 y 23,6 millones de dólares mientras que con GND los costos se reducirían en cerca de un 32 %. Conclusiones El presente estudio es un buen estimador de los potenciales efectos de la universalización del acceso al GND por parte de los hogares más pobres y vulnerables.