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In this chapter, the life cycle impact assessment (LCIA) phase will be addressed, which is fundamental in quantifying environmental impacts according to the goal and scope of each study, as we saw in Chap. 3: Life Cycle Assessment (LCA)—Definition of Goals and Scope.

The main aim of this research is to perform a sensitivity analysis of a Life Cycle Assessment (LCA) case study to understand if the use of different Life Cycle Impact Assessment (LCIA) methods may lead to different conclusions by decision makers and stakeholders. A complete LCA was applied to non-load-bearing external climate walls for comparative purposes. The LCIA phase of the case study was performed using five different Impact Assessment Methods: EDIP 97/2003 (midpoint), CML 2001 (midpoint), Impact 2002+ (endpoint and midpoint), ReCiPe (endpoint and midpoint) and the ILCD recommended practices for LCIA (midpoint). The endpoint results were compared aggregately, and the midpoint categories concerning similar potential impacts were compared individually for the analysis of possible deviations. The observations and comparisons involved mostly the decision maker's point of view and not the differences among the characterization models. The endpoint LCIA showed that the only two methods which applied such an approach (Impact 2002+ and ReCiPe) provided different results and led to different conclusions. For midpoint LCIA, the results were completely consistent for the following impact categories: General Eutrophication, Aquatic and Freshwater Ecotoxicity, Ionizing Radiation, Particulate Matter Formation, and Resources Depletion. Global Warming, Terrestrial Ecotoxicity, Human Toxicity (except for the Non-carcinogens impact category) and Land Use (except for Natural Land Transformation) showed partially consistent results and pointed out to the same worst environmental alternative, but with a slightly different impact profile among the other alternatives. Ozone Layer depletion and Photochemical Oxidant Formation categories showed discrepant results and the impact profile differences between the older and newer methods were notable. Acidification, Terrestrial and Aquatic Eutrophication, Marine Ecotoxicity and Water Depletion showed substantially inconsistent results. (C) 2015 Elsevier Ltd. All rights reserved.

Sugarcane bagasse is one of the main agro-industrial residues which can be used to produce wood-based panels. However, more investigations related to its environmental performance assessment are needed, focusing on questions such as: Does it provide environmental benefits? What are its main environmental impacts? Could it substitute wood as raw material? Accordingly, this paper presents a life cycle assessment (LCA) study of particle board manufactured with sugarcane bagasse residues. The cradle-to-gate assessment of 1 m3 of particle board made with sugarcane bagasse (PSB) considered three main subsystems: bagasse generation, bagasse distribution, and PSB production. For the inventory of PSB, dataset from two previous LCA studies related to the conventional particle board production and the ethanol life cycle for the Brazilian context were used. The allocation criterion for the bagasse generation subsystem was 9.08 % (economic base). The potential environmental impact phase was assessed by applying the CML and USEtox methods. PSB was compared with the conventional particle board manufactured in Brazil by the categories of the CML and USETox, and including land use indicators. Finally, two scenarios were analyzed to evaluate the influence of the allocation criteria and the consumption of sugarcane bagasse. All hotspots identified by CML and USETox methods are mainly related to the PSB production subsystem (24–100 % of impacts) due to heavy fuel oil, electricity, and urea-formaldehyde resin supply chain. The bagasse generation subsystem was more relevant to the eutrophication category (75 % of impacts). The bagasse distribution subsystem was not relevant because the impacts on all categories were lower than 1 %. PSB can substitute the conventional particle board mainly because of its lower contribution to abiotic depletion and ecotoxicity. Regarding land use impacts, PSB showed lower values according to all indicators (38–40 % of all impacts), which is explained by the lower demand for land occupation in comparison to that of the traditional particle board. PSB can replace the traditional particle board due to its better environmental performance. The analysis of the economic allocation criterion was relevant only for the EP category, being important to reduce diesel and N-based fertilizers use during sugarcane cultivation. Regarding the influence of the sugarcane bagasse consumption, it is suggested that the sugarcane bagasse be mixed up to 75 % during particle board manufacturing so that good quality properties and environmental performance of panels can be provided.

Resumo Avaliação de Impacto do Ciclo de Vida (AICV) é a terceira fase da Avaliação do Ciclo de Vida (ACV) e tem como finalidade avaliar a significância ambiental dos resultados do inventário por meio de modelos e fatores de caracterização contidos nos métodos de AICV. Nesse contexto, este trabalho tem como objetivo identificar os principais métodos de AICV e descrever suas características. Por meio de uma revisão da literatura foram identificados 13 métodos de AICV, desenvolvidos majoritariamente em países da Europa e utilizados em todo o mundo, inclusive no Brasil. Dentre esses métodos foram reconhecidos aqueles que apresentam escopo de aplicação global, sendo recomendados para uso no Brasil. Cada método de AICV avalia as diferentes categorias de impacto por meio de uma série de modelos de caracterização, assim, concluiu-se ser necessário analisarem-se os procedimentos de cálculos utilizados por cada modelo, a fim de fornecer subsídios para aplicação desses métodos e modelos nas diferentes regiões do mundo. Abstract Life Cycle Impact Assessment (LCIA) is the third phase of Life Cycle Assessment (LCA). It involves assessing the environmental significance of inventory results by using characterization models and factors contained in LCIA methods. This paper identifies the main LCIA methods and describes their characteristics. Through a literature review, 13 LCIA methods were identified. Most of them were developed in Europe and have been used throughout the world, including Brazil. Among these methods have been identified those with a global scope of application, being recommended for the use in Brazil. Each LCIA method evaluates different impact categories by means of a number of different characterization models, so it was concluded that there is a need to analyze the calculation procedures used by each model to provide support for the application of these methods and models in different regions of the world.

This paper presents a Life Cycle Assessment comparison using CML (2001), EDIP (1997) and USETox (2008) methods for the impact assessment of urea formaldehyde resin (UF) used in the production of wood panels in Brazil. The impact results were focused just on toxicological categories like human toxicity and ecotoxicity. The main hotspots of UF resin were free formaldehyde air emissions to aquatic and terrestrial ecotoxicity and for human toxicity category, the results showed that emissions to air of nitrogen oxides from urea (raw material) are also very important and not just free formaldehyde air emissions like previously checked in literature.