RESUMEN
A Life Cycle Impact Assessment method was developed to evaluate the environmental impact associated with salinity on biodiversity in a Spanish coastal wetland. The developed characterization factor consists of a fate and an effect factor and equals 3.16 × 10(-1) ± 1.84 × 10(-1) PAF · m(3) · yr · m(-3) (PAF: Potentially Affected Fraction of species) indicating a "potential loss of 0.32 m(3) ecosystem" for a water consumption rate of 1 m(3) · yr(-1). As a result of groundwater consumption with a rate of 1 m(3) · yr(-1), the PAF in the lost cubic meter of ecosystem equals 0.05, which has been proposed as the maximum tolerable effect to keep the ecosystem intact. The fate factor was calculated from seasonal water balances of the wetland Albufera de Adra. The effect factor was obtained from the fitted curve of the potentially affected fraction of native wetland species due to salinity and can be applied to other wetlands with similar species composition. In order to test the applicability of the characterization factor, an assessment of water consumption of greenhouse crops in the area was conducted as a case study. Results converted into ecosystem quality damage using the ReCiPe method were compared to other categories. While tomatoes are responsible for up to 30% of the impact of increased salinity due to water consumption on ecosystem quality in the studied area, melons have the largest impact per tonne produced.
Asunto(s)
Monitoreo del Ambiente/métodos , Humedales , Biodiversidad , Ecosistema , SalinidadRESUMEN
Milk is a very important part of our diet, which is why there is a wide variety of packaging alternatives with considerable local variants on the market. This study assesses the environmental impact of the commonest packaging options on the Spanish market and evaluates (from the point of view of global warming and acidification) the production of the various packaging materials and sizes and their final disposal (landfilling, incineration and recycling). For the two indicators studied (global warming and acidification) larger aseptic carton packages and recycling disposal have the best environmental impact. The global warming and acidification potential of the milk life cycle were also studied: milk production, transport (local conditions), packaging production and packaging disposal. Of the two indicators studied, the milk production stage has the largest impact on the milk life cycle. It should be taken into account that the impact of the milk production stage can vary considerably and has a significant influence on the global warming and acidification potential of the milk life cycle.
Asunto(s)
Ambiente , Leche , Animales , Productos Lácteos , Calentamiento Global , Embalaje de Productos , Administración de ResiduosRESUMEN
The main function of a Wastewater Treatment Plant is to minimize the environmental impact of discharging untreated water into natural water systems. Also a Wastewater Treatment Plant may get a resource from wastewater carrying out a tertiary treatment on the treated wastewater which can be reused in non-potable applications. Water reuse strategies are intended to address the problem of water scarcity without aggravating other environmental problems, thus reflecting the need of their environmental assessment. In this paper we used Life Cycle Assessment to evaluate different disinfection treatments (chlorination plus ultraviolet treatment, ozonation and ozonation plus hydrogen peroxide) and to assess the environmental advantages and drawbacks of urban wastewater reuse in non-potable applications. To do so, we compared the environmental impacts of producing 1m(3) of water for non-potable uses from reclaimed water, potable water and desalinated water sources. The calculation has used current operating data from a Wastewater Treatment Plant located in the Mediterranean area, although the results can be applied to any other plant with similar technology. The ozonation and ozonation plus hydrogen peroxide disinfection treatment technologies have similar environmental profiles. However most of the indicators are about 50% higher than the ultraviolet disinfection except for the acidification (100% higher) and photochemical oxidation (less than 5%). Non-potable uses (both agricultural and urban uses) of reclaimed water have environmental and economical advantages. Reuse of treated wastewater is particularly beneficial when it can replace desalinated water. Consequently, reclaimed water should be promoted for non-potable uses, when there is scarcity of freshwater.
Asunto(s)
Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Ciudades , Conservación de los Recursos Naturales/métodos , Desinfección/métodos , Nitrógeno/análisis , Contaminantes del Agua/análisisRESUMEN
The main objective of this paper is to study and quantify the differences in energy consumption and environmental impacts of two dwellings during the full building life cycle: one in Spain, a developed country, and one in Colombia, a country under development. In both scenarios, we assessed the construction, use and end-of-life phases. Results show that the use phase in the Pamplona house (Colombia) represents a lower percentage for all impacts in the total than in the Barcelona house (Spain). The findings of this study showed that the difference in consumption in Colombia and Spanish dwellings analysed is not only due to the variation in results for bio-climatic differences but also because of the consumption habits in each country. The importance of consumption habits of citizens and the need to decouple socio-economic development from energy consumption are sought for achieving sustainability from a life cycle perspective. There is a crucial necessity to provide satisfaction to basic needs and comfort requirements of population with reasonable and sustainable energy consumption. Then, the type of standard dwelling varies substantially depending on the geographic location where it is built. Climate, technological, cultural, socio-economical differences clearly define the standard of a building in any context and in any region. However, the function is always the same, to provide protection and housing for its habitants.
Asunto(s)
Países Desarrollados , Países en Desarrollo , Monitoreo del Ambiente , Vivienda/clasificación , Colombia , Conservación de los Recursos Energéticos , Materiales de Construcción/estadística & datos numéricos , Fuentes Generadoras de Energía/estadística & datos numéricos , España , Remodelación UrbanaRESUMEN
Life cycle assessment (LCA) methodology is used to evaluate the environmental profile of a product or process from its origin to its final destination. In this paper we used LCA to evaluate the current situation of a wastewater treatment plant and identify improvement alternatives. Currently, the highest environmental impacts are caused by the stages of the plant with the highest energy consumption, the use of biogas from anaerobic digestion (95% burned in torch) and the final destination of the sludge (98.6% for agricultural use and 1.4% for compost). We propose four alternatives for biogas applications and five alternatives for sludge applications and compare them to the current situation. The alternatives were incorporated in a decision support system to identify and prioritize the most positive environmental option. Using biogas to produce electricity or a combination of electricity and heat provided the best environmental options since the energy produced would be enough to supply all the stages of the plant, thus reducing their environmental impact. The best environmental option for the final destination of the sludge is to combine the current situation (fertilizer replacement) with use of the sludge in a cement plant (as a replacement for fuel and raw material).
Asunto(s)
Ciudades , Técnicas de Apoyo para la Decisión , Ambiente , Eliminación de Residuos Líquidos , Purificación del Agua , Anaerobiosis , Biodegradación Ambiental , Fuentes de Energía Bioeléctrica , Aguas del Alcantarillado/microbiología , EspañaRESUMEN
Management of municipal solid waste (MSW) has become a significant environmental problem, especially in fast-growing cities. The amount of waste generated increases each year and this makes it difficult to create solutions which due to the increase in waste generation year after year and having to identify a solution that will have minimum impact on the environment. To determine the most sustainable waste management strategy for Chihuahua, it is first necessary to identify the nature and composition of the city's urban waste. The MSW composition varied considerably depending on many factors, the time of year is one of them. Therefore, as part of our attempt to implement an integral waste management system in the city of Chihuahua, we conducted a study of the characteristics of MSW composition for the different seasons. This paper analyzes and compares the findings of the study of the characterization and the generation of solid waste from households at three different socio-economic levels in the city over three periods (April and August, 2006 and January, 2007). The average weight of waste generated in Chihuahua, taking into account all three seasons, was 0.592 kg capita(-1) day(-1). Our results show that the lowest income groups generated the least amount of waste. We also found that less waste was generated during the winter season. The breakdown for the composition of the waste shows that organic waste accounts for the largest proportion (45%), followed by paper (17%) and others (16%).
Asunto(s)
Residuos/estadística & datos numéricos , México , Estaciones del Año , Factores Socioeconómicos , Población UrbanaRESUMEN
The uptake and persistence behaviour of the insecticide imidacloprid in tomato plants treated by (i) foliar spray application and (ii) soil irrigation was studied using two plant uptake models. In addition to a pesticide deposition model, a dynamic root uptake and translocation model was developed, and both models predict residual concentrations of pesticides in or on fruits. The model results were experimentally validated. The fraction of imidacloprid ingested by the human population is on average 10(-2) to 10(-6), depending on the time between pesticide application and ingestion, the processing step, and the application method. Model and experimentally derived intake fractions deviated by less than a factor of 2 for both application techniques. Total imidacloprid residues were up to five times higher in plants treated by foliar spray application than by soil irrigation. However, peeling tomatoes treated by spray application reduces the human intake fraction by up to three orders of magnitude. Model calculations suggest that drip-irrigation in a closed hydroponic system minimizes worker and consumer exposure to pesticides and prevents runoff of pesticide by spray drift and leaching into the environment.
Asunto(s)
Imidazoles/farmacocinética , Nitrocompuestos/farmacocinética , Plaguicidas/farmacocinética , Plantas/metabolismo , Ingestión de Alimentos , Contaminación de Alimentos , Humanos , Solanum lycopersicum/metabolismo , Modelos Biológicos , Neonicotinoides , Raíces de Plantas/metabolismoRESUMEN
The characterization of urban solid waste generation is fundamental for adequate decision making in the management strategy of urban solid waste in a city. The objective of this study is to characterize the waste generated in the households of Chihuahua city, and to compare the results obtained in areas of the city with three different socioeconomic levels. In order to identify the different socioeconomic trends in waste generation and characterization, 560 samples of solid waste were collected during 1 week from 80 households in Chihuahua and were hand sorted and classified into 15 weighted fractions. The average waste generation in Chihuahua calculated in this study was 0.676 kg per capita per day in April 2006. The main fractions were: organic (48%), paper (16%) and plastic (12%). Results show an increased waste generation associated with the socioeconomic level. The characterization in amount and composition of urban waste is the first step needed for the successful implementation of an integral waste management system.
Asunto(s)
Eliminación de Residuos , Residuos/clasificación , Ciudades , Conservación de los Recursos Naturales , Americanos Mexicanos , Factores SocioeconómicosRESUMEN
Degradation half-lives in/on vegetation are needed in environmental risk assessment of pesticides, but these data are often not available for most active ingredients. To address this, we first correlated experimental soil degradation half-life data of 41 pesticides obtained from the reviewed literature with the corresponding experimental half-lives on plant surface. Degradation half-lives in soil were found to be four times slower compared with half-lives on plant surfaces. In a second step, we explored measured plant surface half-lives directly with those in vegetation. The results were validated by comparing computed values with results obtained from an experimental set-up. The uptake and dissipation of alpha-cypermethrin (insecticide) and bromopropylate (acaricide) was studied by detecting pesticide residues in whole and peeled tomato fruits using gas chromatography. Half-lives within vegetation were found to be four times faster compared with plant surface half-lives. Using this experimental based approach, it is concluded that the estimation of degradation half-lives of pesticides in/on vegetation to be used as input data in environmental mass balance models can be directly correlated from the more abundant ready experimental degradation half-life data for soil.
Asunto(s)
Bencilatos/metabolismo , Modelos Biológicos , Residuos de Plaguicidas/metabolismo , Piretrinas/metabolismo , Solanum lycopersicum/metabolismo , Frutas/metabolismo , SemividaRESUMEN
A chemical ranking and scoring method entitled PestScreen has been developed as a screening tool to provide a relative assessment of pesticide hazards to human health and the environment. The method was developed to serve as an analytical tool in screening and identification of pesticides of environmental concern used in agriculture. PestScreen incorporates both the toxic effects of pesticides and their fate and exposure characteristics in different compartments of the environment. This is done by combining measures of chemical toxicity pertaining to both human health and the environment with chemical release amounts and information on overall environmental persistence, long-range transport potential and human population intake fractions. Each hazard measure is scored and weighted and finally combined with the pesticide application dose to provide a single final indicator of relative concern (PestScore). Results for 217 pesticides are presented and the practical implementation is illustrated on behalf of three practical case studies.
Asunto(s)
Contaminantes Ambientales/toxicidad , Plaguicidas/toxicidad , Pruebas de Toxicidad/métodos , Animales , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/farmacocinética , Contaminación Ambiental/prevención & control , Humanos , Medición de RiesgoRESUMEN
The estimation of damage estimates due to air emissions gives important basic knowledge for decision-making on the level of environmental politics and business strategies. Nowadays, a frequently applied method to estimate environmental damages is the Impact Pathway Analysis (IPA), which can be easily carried out using models such as EcoSense or PathWays. These models produce results in a relatively short term. However, there is a lack of reliability in the results. As in many other environmental software tools, the uncertainty is the key problem that makes it difficult to convince decision-makers by the outcomes of a study. Therefore, a framework that allows assessing the uncertainties within studies in which the IPA is applied on a local scale has been developed. In this assessment framework, the uncertainties of the used parameters, including their spatial and temporal variability, are taken into account. As the model is processing a huge quantity of data, one step of the assessment consists of a screening procedure to determine the parameters that are supposed to be fixed. For the other data, probability distributions have to be selected and classified into two groups: extensively available data for which average and standard deviation can be calculated and data based on little information. A quantification of the uncertainty can be completed by a stochastic model in the form of Monte Carlo (MC) simulation on the basis of the framework. As an illustration of the framework, we have applied it to a study on the installation of an advanced gas treatment in the municipal waste incinerator of Tarragona. It can be shown that the presented stochastic approach gives a lower geometric deviation than the analytical one and that the new gas treatment reduces the environmental damages without any doubt.