RESUMEN
BACKGROUND@#Early studies show e-reading to be better in some impact assessment indicators. However, newer studies on Information and Communication Technology (ICT) devices shows various role of user behavior, device properties, and media properties in calculated environmental impacts. There is a need to study scenarios of media use such as printed media and its digitized forms to determine use scenarios that would minimize environmental impacts.@*OBJECTIVES@#The objectives of the study are the following: to model the life cycle from cradle to use phase of reading one textbook in both print and e-book format and to compare the impact of reading textbooks in print with impact of reading textbooks in E-book format.@*METHODS@#A functional unit of 280-page textbook read in 1 year was the basis for modelling life cycle from cradle to use phase of both print and e-book formats of a textbook. Processes related to paper production, printing and manufacture are based on United States Life Cycle Inventory Database. Processes related to E-book reading are taken from the Life Cycle Analysis of Sony Z5 mobile Phone. Normalized outputs on impact assessments were compared using Tools for Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI 2.1).@*RESULTS@#Use of Mobile Phone to read e-books is better in 4 out of 7 impact categories (Acidification Potential, Human Health-Cancer, Human Health – non-Cancer and Ozone Depletion) than reading using traditional textbooks. Reading traditional books is better in 2 out of 7 impact categories (Eutrophication and Freshwater Ecotoxicity). Global warming potential has comparable values between reading in print and in soft copy. @*CONCLUSION@#Depending on impact assessment of concern, either reading using mobile phone or thru printed textbook would give a better impact. It is also suggested to create hybrid activities that could model scenarios using both printed and soft copies of textbooks.
RESUMEN
Background: Bioethanol is produced mainly from sugar cane and corn. In the last years it has been subject of debate due to the effects in food prices and land use change. The use of lignocellulosic materials for bioethanol production, such as agroindustry, forestry and municipal residues, wood or dendroenergetic species, has been proposed as a sustainable way for producing this biofuel. The design of a sustainable process for producing bioethanol requires a methodological approach whereby economical, environmental and social criteria are systematically integrated from the early stages of process design. Results: Until now a methodology for guiding the design of a sustainable process for bioethanol production is not available, and there are just a few studies on this subject. Moreover, with the recent global concerns on climate change, developed technologies have been confronted with additional requirements to validate their sustainability. In this sense, the inclusion of sustainability criteria on process design becomes necessary for defining a systematic methodology to select the most appropriate operations in the process stages to achieve a sustainable bioethanol production. Conclusions: A description of the stages for the production of bioethanol from lignocellulosic materials is provided in this review and the main findings in relation to the more important sustainability indicators are presented.