Trypanosoma cruzi: Correlations of Biological Aspects of the Life Cycle in Mice and Triatomines

The infection pattern in Swiss mice and Triatomine bugs (Rhodnius neglectus) of eleven clones and the original stock of a Trypanosoma cruzi isolate, derived from a naturally infected Didelphis marsupialis, were biochemically and biologically characterized. The clones and the original isolate were in the same zymodeme (Z1) except that two clones were found to be in zymodeme 2 when tested with G6PDH. Although infective, neither the original isolate nor the clones were highly virulent for the mice and lesions were only observed in mice infected with the original stock and one of the clones (F8). All clones and the original isolate infected bugs well while only the original isolate and clones E2 and F3 yielded high metacyclogenesis rates. An observed correlation between absence of lesions in the mammal host and high metacyclogenesis rates in the invertebrate host suggest a evolutionary trade off i.e. a fitness increase in one trait which is accompanied by a fitness reduction in a different one. Our results suggest that in a species as heterogeneous as T. cruzi, a cooperation effect among the subpopulations should be considered.

Aspects of the Maintenance of the Life Cycle of Fasciola hepatica in Lymnaea columella in Minas Gerais, Brazil

Fascioliasis is a parasitic disease of domestic ruminants that occurs worldwide. The lymnaeid intermediate hosts of Fasciola hepatica include Lymnaea columella, which is widely distributed in Brazil. A colony of L. columella from Belo Horizonte, MG, was reared in our laboratory to be used in studies of the F. hepatica life cycle, the intermediate host-parasite relationship and development of an anti-helminthic vaccine. In the first experiment 1,180 snails were exposed to miracidia of F. hepatica eggs removed from the biliary tracts of cattle from the State of Rio Grande do Sul. In the second and third experiments the snails were exposed to miracidia that had emerged from F. hepatica eggs from Uruguay, maintained in rabbits. The rates of infection in the first, second and third experiments were 0, 42.1 and 0% respectively. Over 15,806 metacercariae were obtained and stored at 4ºC. Four rabbits weighing 1.5 kg each were infected with 32-44 metacercariae and two with 200. Three rabbits begin to eliminate eggs of the parasite in the feces from 84 days after infection onwards. The biological cycle of F. hepatica in L. columella and the rabbit was completed within 124 days.

Integrating human indoor air pollutant exposure within Life Cycle Impact Assessment.

Neglecting health effects from indoor pollutant emissions and exposure, as currently done in Life Cycle Assessment (LCA), may result in product or process optimizations at the expense of workers' or consumers' health. To close this gap, methods for considering indoor exposure to chemicals are needed to complement the methods for outdoor human exposure assessment already in use. This paper summarizes the work of an international expert group on the integration of human indoor and outdoor exposure in LCA, within the UNEP/ SETAC Life Cycle Initiative. A new methodological framework is proposed for a general procedure to include human-health effects from indoor exposure in LCA. Exposure models from occupational hygiene and household indoor air quality studies and practices are critically reviewed and recommendations are provided on the appropriateness of various model alternatives in the context of LCA. A single-compartment box model is recommended for use as a default in LCA, enabling one to screen occupational and household exposures consistent with the existing models to assess outdoor emission in a multimedia environment. An initial set of model parameter values was collected. The comparison between indoor and outdoor human exposure per unit of emission shows that for many pollutants, intake per unit of indoor emission may be several orders of magnitude higher than for outdoor emissions. It is concluded that indoor exposure should be routinely addressed within LCA.

Inclusion of soil erosion impacts in life cycle assessment on a global scale: application to energy crops in Spain

Purpose: Despite the fundamental role of ecosystem goods and services in sustaining human activities, there is no harmonized and internationally agreed method for including them in life cycle assessment (LCA). The main goal of this study was to develop a globally applicable and spatially resolved method for assessing land-use impacts on the erosion regulation ecosystem service.Methods: Soil erosion depends much on location. Thus, unlike conventional LCA, the endpoint method was regionalized at the grid-cell level (5 arc-minutes, approximately 10×10 km2) to reflect the spatial conditions of the site. Spatially explicit characterization factors were not further aggregated at broader spatial scales. Results and discussion: Life cycle inventory data of topsoil and topsoil organic carbon (SOC) losses were interpreted at the endpoint level in terms of the ultimate damage to soil resources and ecosystem quality. Human health damages were excluded from the assessment. The method was tested on a case study of five three-year agricultural rotations, two of them with energy crops, grown in several locations in Spain. A large variation in soil and SOC losses was recorded in the inventory step, depending on climatic and edaphic conditions. The importance of using a spatially explicit model and characterization factors is shown in the case study.Conclusions and outlook: The regionalized assessment takes into account the differences in soil erosion-related environmental impacts caused by the great variability of soils. Taking this regionalized framework as the starting point, further research should focus on testing the applicability of the method trough the complete life cycle of a product and on determining an appropriate spatial scale at which to aggregate characterization factors, in order to deal with data gaps on location of processes, especially in the background system. Additional research should also focus on improving reliability of the method by quantifying and, insofar as it is possible, reducing uncertainty.

Life cycle analysis and life cyle impact assessment methodologies: a state of the art

Life cycle analysis (LCA) is a comprehensive method for assessing the environmental impact of a product or an activity over its entire life cycle. The purpose of conducting LCA studies varies from one application to another. Different applications use LCA for different purposes. In general, the main aim of using LCA is to reduce the environmental impact of products through guiding the decision making process towards more sustainable solutions. The most critical phase in an LCA study is the Life Cycle Impact Assessment (LCIA) where the life cycle inventory (LCI) results of the considered substances related to the study of a certain system are transformed into understandable impact categories that represent the impact on the environment. In this research work, a general structure clarifying the steps that shall be followed ir order to conduct an LCA study effectively is presented. These steps are based on the ISO 14040 standard framework. In addition, a survey is done on the most widely used LCIA methodologies. Recommendations about possible developments and suggetions for further research work regarding the use of LCA and LCIA methodologies are discussed as well.

Impact of increased environmental awareness on product marketing

This Bachelor thesis studies how companies use a variety of different sustainable marketing approaches to sell their green products. Empirical part is done by researching and interviewing two B2B furniture companies.

Applying life cycle management of colombian cocoa production

The present research aims to evaluate the usefulness of the application of Life Cycle Management in the agricultural sector focusing on the environmental and socio-economic aspects of decision making in the Colombian cocoa production. Such appraisal is based on the application of two methodological tools: Life Cycle Assessment, which considers environmental impacts throughout the life cycle of the cocoa production system, and Taguchi Loss Function, which measures the economic impact of a process' deviation from production targets. Results show that appropriate improvements in farming practices and supply consumption can enhance decision-making in the agricultural cocoa sector towards sustainability. In terms of agri-business purposes, such qualitative shift allows not only meeting consumer demands for environmentally friendly products, but also increasing the productivity and competitiveness of cocoa production, all of which has helped Life Cycle Management gain global acceptance. Since farmers have an important role in improving social and economic indicators at the national level, more attention should be paid to the upgrading of their cropping practices. Finally, one fundamental aspect of national cocoa production is the institutional and governmental support available for farmers in face of socio-economic or technological needs.

Environmental and human health impacts of growing genetically modified herbicide-tolerant sugar beet: a life-cycle assessment

There is ongoing debate concerning the possible environmental and human health impacts of growing genetically modified (GM) crops. Here, we report the results of a life-cycle assessment (LCA) comparing the environmental and human health impacts of conventional sugar beet growing regimes in the UK and Germany with those that might be expected if GM herbicide-tolerant (to glyphosate) sugar beet is commercialized. The results presented for a number of environmental and human health impact categories suggest that growing the GM herbicide-tolerant crop would be less harmful to the environment and human health than growing the conventional crop, largely due to lower emissions from herbicide manufacture, transport and field operations. Emissions contributing to negative environmental impacts, such as global warming, ozone depletion, ecotoxicity of water and acidification and nutrification of soil and water, were much lower for the herbicide-tolerant crop than for the conventional crop. Emissions contributing to summer smog, toxic particulate matter and carcinogenicity, which have negative human health impacts, were also substantially lower for the herbicide-tolerant crop. The environmental and human health impacts of growing GM crops need to be assessed on a case-by-case basis using a holistic approach. LCA is a valuable technique for helping to undertake such assessments.

An application of life-cycle assessment for environmental planning and management: the potential environmental and human health impacts of growing genetically-modified herbicide-tolerant sugar beet

Life-Cycle Assessment (LCA) was used to assess the potential environmental and human health impacts of growing genetically-modified (GM), herbicide-tolerant sugar beet in the UK and Germany compared with conventional sugar beet varieties. The GM variety results in lower potential environmental impacts on global warming, airborne nutrification, ecotoxicity (of soil and water) and watercourse enrichment, and lower potential human health impacts in terms of production of toxic particulates, summer smog, carcinogens and ozone depletion. Although the overall contribution of GM sugar beet to reducing harmful emissions to the environment would be relatively small, the potential for GM crops to reduce pollution from agriculture, including diffuse water pollution, is highlighted.

The use of life cycle assessment to compare the environmental impact of production and feeding of conventional and genetically modified maize for broiler production in Argentina

The paper presents the methods and results of a life-cycle assessment (LCA) applied to the production of maize grain from a conventional variety compared with maize grain from a variety genetically modified to be herbicide tolerant and insect protected and to contain an enhanced oil and lysine content, and its impact when fed to broiler chickens. The findings show that there are both environmental and human health benefits of growing GM maize including lower impacts on global warming, ozone depletion, freshwater ecotoxicity and human toxicity. However, when considered in terms of the use of maize as a feed input to broiler chicken production, the benefits of the GM alternative become negligible compared to the use of conventional maize.

The use of life-cycle assessment to evaluate the environmental impacts of growing genetically modified, nitrogen use-efficient canola

Agriculture, particularly intensive crop production, makes a significant contribution to environmental pollution. A variety of canola (Brassica napus) has been genetically modified to enhance nitrogen use efficiency, effectively reducing the amount of fertilizer required for crop production. A partial life-cycle assessment adapted to crop production was used to assess the potential environmental impacts of growing genetically modified, nitrogen use-efficient (GMNUE) canola in North Dakota and Minnesota compared with a conventionally bred control variety. The analysis took into account the entire production system used to produce 1 tonne of canola. This comprised raw material extraction, processing and transportation, as well as all agricultural field operations. All emissions associated with the production of 1 tonne of canola were listed, aggregated and weighted in order to calculate the level of environmental impact. The findings show that there are a range of potential environmental benefits associated with growing GMNUE canola. These include reduced impacts on global warming, freshwater ecotoxicity, eutrophication and acidification. Given the large areas of canola grown in North America and, in particular, Canada, as well as the wide acceptance of genetically modified varieties in this area, there is the potential for GMNUE canola to reduce pollution from agriculture, with the largest reductions predicted to be in greenhouse gases and diffuse water pollution.