Autor(es): Kurt Ziegler Rodríguez, Ian Vázquez Rowe, Ramzy Kahhat Abedrabbo y otros
Waste remains a serious environmental and human health hazard in developing nations, including those in Latin America and the Caribbean (LA&C). Despite important breakthroughs in waste management in LA&C, the region still faces many challenges that require special attention, such as the existence of uncontrolled open dumpsters (33%) or the low recovery rates of waste fractions (below 4%). Moreover, the adoption of sophisticated waste management technologies, such as incineration or anaerobic digestion, is still lagging. This review paper provides environmentally-sound and relevant policy support for municipal solid waste management stakeholders through a critical review of the current situation of the waste management sector in LA&C from an environmental perspective. Thereafter, Life Cycle Assessment (LCA) bibliography linked to waste management, namely collection, sorting, recycling and landfilling applications and technologies worldwide, is used in order to understand potential alternative waste management strategies in LA&C, as well as the potential environmental benefits that could be attained. Finally, based on the holistic review and analysis, the adoption of more sophisticated technologies in landfill sites (e.g. landfill gas flaring), waste-to-energy, as well as higher recycling rates, would enhance waste management in the region and mitigate environmental impacts. A holistic view to support policy formulations, including climate action, for the adoption of integrated waste management strategies in LA&C is imperative.
Ir al enlaceAutor(es): Ian Vázquez Rowe y otros
Purpose: The main purpose of this article is to assess the nutritional and economic efficiency of food loss and waste (FLW) along the supply of 13 food categories included in the Spanish food basket by means of the definition of a new method which combines two indexes. Methods: The nutrient-rich foods index and the economic food loss and waste (EFLW) index were combined by means of linear programming to obtain the nutritional cost footprint (NCF) indicator under a life cycle perspective. The functional unit used was the daily supply of food for a Spanish citizen in year 2015. Results and discussion: Results showed that vegetables and cereals were the food categories most affected by the inefficiencies in the food supply chain under a nutritional perspective, being agricultural production and household consumption the main stages in which the nutritional content of food is lost or wasted. Moreover, according to the NCF index, vegetables represented 27% of total nutritional-economic wastage throughout the entire Spanish agri-food chain. They are followed by fruits, which add up to 19%. Hence, specific food waste management strategies should be established for these specific products and supply stages. Finally, the sensitivity analysis performed highlighted that results were mostly independent from the importance attributed to either nutritional or economic variables. Conclusions: The methodology described in this study proposes an indicator quantifying the nutritional-economic cost of different food categories in the Spanish food basket. This NCF indicator makes it possible to define reduction strategies to promote the use of food waste fractions for waste-to-energy valorization approaches or the extraction of different types of pharmacological, chemical, or cosmetic compounds.
Ir al enlaceAutor(es): Ian Vázquez Rowe y otros
Food losses and waste (FLW) tend to be referred to in terms of mass, occasionally in economic terms, disregarding the nutritional-cost nexus of such losses. This work aims to estimate the nutritional food losses and waste (NFLW) of the Spanish agri-food system in terms of energy, macronutrients, fibre, and vitamins and minerals along the entire supply chain. Nutritional food losses (NFL) occurring prior to the distribution level, and nutritional food waste (NFW) at the retail and consumption stages, were distinguished, and 48 representative food commodities and 32 nutrients were characterised. To provide insight into the extent of these values, the results are compared to the equivalent recommended daily intake. In addition, the NFLW for an average Spanish citizen is compared to that for other representative diets: Mediterranean, lacto-ovo-vegetarian, and vegan along with the Spanish recommended guidelines. Finally, a nutritional cost footprint (NCF) indicator combining nutritional and economic variables is proposed to define recovery strategies. The results suggest that 4251 kj (1016 kcal), 70.7 g proteins, 22 g dietary fibre, 975 μg vitamin A, 117 mg vitamin C and 332 mg calcium daily per capita are embedded within Spanish FLW. Agricultural production accounts for 40% of NFLW, and fruits and vegetables are the categories with the largest potential for nutritional and economic food wastage mitigation. Results from this paper provide NFLW data and analysis to strengthen and simplify the decision-making process of FLW management strategies.
Ir al enlaceAutor(es): Ian Vázquez Rowe y otros
The management of vineyards depends on the use of plant protection agents. Regardless of the numerous environmental impacts that these pesticides generate during their production, their dosage as pest control agents in vineyards causes an important toxic effect that must be monitored. Copper-based inorganic pesticides are the most widely used agents to control fungal diseases in humid wine-growing regions. It is, however, significant that the environmental analysis of their use through the Life Cycle Assessment (LCA) methodology does not provide detailed information on the potential toxicity of this type of pesticides. Hence, most studies report average values for copper characterization factors (CFs), excluding local soil characteristics. The objective of the study was the spatial characterization of the ecotoxicity factors of copper soil emissions as a function of the chemical characteristics of vineyard soils located in Portugal and Galicia (NW Spain). A multiple linear regression model was applied to calculate the comparative toxic potential. Subsequently, CFs for copper were calculated based on spatial differentiation considering the variable properties of the soil within each wine appellation. The CFs obtained for the area evaluated ranged from 141 to 5937 PAF·m3·day/kgCu emitted, for fibric histosols (HSf) and dystic cambisols (CMd), respectively. Moreover, the average values obtained for Galician and Portuguese soils were 1145 and 2274 PAF·m3·day/kgCu emitted, respectively. The results obtained illustrate the high variability of CF values as a function of the chemical characteristics of each type of soil. For example, Cu soil mobility was linked to organic carbon content and pH. Finally, to validate the representativeness of the calculated CFs, these were applied to the results of 12 literature life cycle inventories of grape production in the area evaluated, revealing that impact scores associated with Cu emissions can considerably vary when spatially-differentiated CFs are implemented.
Ir al enlaceAutor(es): Kurt Ziegler Rodríguez, Ian Vázquez Rowe, Ramzy Kahhat Abedrabbo y otros
The Peruvian waste management sector is steadily transitioning from a mostly informal and underdeveloped system based on the use of open dumpsters to a landfill-based system. The environmental consequences of these policies must be evaluated with environmental management tools such as Life Cycle Assessment (LCA). Therefore, the main goal of the study is to analyze the life-cycle environmental performance of waste disposition in three different landfills located in three distinct geographical areas of Peru: i) the hyper-arid coast; ii) the Andean highlands; and, iii) the Amazon Rainforest. With this aim in mind, a comparative analysis is provided regarding the waste treatment process as compared to other landfill technologies (i.e., biogas combustion or energy recovery) and open dumpsters. The modelling of these systems was performed with the EASETECH waste LCA tool, including a sensitivity analysis in terms of waste composition and waste decay rates. Results show that landfill gas (LFG) treatment reduces greenhouse gas (GHG) emissions considerably. However, these remain higher in the Amazon as compared to the Andean Highlands (+105%) and the hyper-arid coast (+17%). Most of the decomposition in the Amazon basin occurs within 5 years after disposition (80%) due to heat and humidity, whereas in the other regions values were below 55%. LFG treatment or recovery is necessary for these emissions to be lower than in open dumpsters. The implementation of these technologies would strengthen the country's action plan regarding the Paris Agreement in the waste sector. In other impact categories, the transitioning from dumpsters to landfills is most visible in the soil and water compartments.
Ir al enlaceAutor(es): Ramzy Kahhat Abedrabbo, Eduardo Parodi Gonzales Prada, Gustavo Larrea Gallegos, Carlos Mesta Cornetero, Ian Vázquez Rowe
Alluvial gold mining activities in the Peruvian Amazon rainforest are responsible for mercury emissions and deforestation. To understand related environmental impacts, specifically toxicity and climate change, this study uses Life Cycle Assessment methodology. Four predominant extraction systems were selected and modelled and three scenarios that reflect currently available gold recovery systems were modelled: amalgamation, amalgamation with mercury recovery through retort system and gravimetric tables. The USEtox and IPCC life cycle impact assessment methods were used to assess the environmental impacts in term of human toxicity, freshwater ecotoxicity and climate change. Results show that for all systems, human toxicity values are governed by mercury emissions in gold recovery activities (ca. 80%). However, the use of retort significantly lowers these impacts (ca. 90%). Machines and diesel use for ore extraction and freighting activities drive freshwater ecotoxicity. Moreover, deforestation has a major contribution on the environmental impacts related to climate change. However, these impacts are dependent on the type of extraction system. Although human toxicity, freshwater ecotoxicity and climate change are frequently studied separately, a direct relationship between them has been identified in this system. Finally, beyond the environmental burdens related to alluvial gold mining, there are impacts affecting the social, cultural, and economic dimensions that will need to be analyzed to ensure a comprehensive understanding of the system.
Ir al enlaceAutor(es): Daniel Verán Leigh, Ian Vázquez Rowe
Purpose: Low-carbon emissions are usually related to hydropower energy, making it an attractive option for nations with hydropower potential as it enables them to meet increasing electricity demand without relying on burning fossil fuels. In fact, the new wave of hydropower plant construction is occurring mainly in tropical areas where an additional environmental impact must be considered: biogenic greenhouse gas (GHG) emissions due to the degradation of biogenic carbon in reservoirs. Peru is planning to install up to 2000 MW in hydropower until 2021, but the input and output flows, as well as the environmental impacts that these generate, have not been explored. Hence, a set of three hydropower plants built in the past decade located in the Peruvian Andes were analyzed from a life cycle perspective. The main objective of the study is to generate detailed life cycle inventories for each of these three hydropower plants with the aim of obtaining specific information for current conditions in Peru. Methods: The life cycle assessment methodology was applied to compute the environmental impacts. Data collection was based mainly on primary data obtained directly from the hydropower companies, although biogenic emissions were modeled considering local net primary productivity conditions and other site-specific conditions. Although the calculation of GHG emissions related to hydropower plants was a priority, considering the important policy implications of decarbonizing the Peruvian electricity grid, other environmental categories, such as eutrophication or the depletion of abiotic resources, were also considered. The IPCC method was used to calculate GHG emissions, whereas a set of eight additional impact categories were computed using the ReCiPe 2016 method. Results and discussion: Results show that GHG emissions per unit of electricity generated were in the lower range of emissions observed in the literature, in all three cases below 3 g CO2eq/kWh. Biogenic emissions represented less than 5% of the total GHG emissions despite their location in a tropical nation, due to the arid conditions of the landscape in the Andean Highlands, as well as the mild temperatures that are present in the reservoirs. In terms of stratospheric ozone depletion, a GHG with ozone depletion properties, N2O, was the main source of impact. Conclusions: The results are intended to be of utility for an array of applications, including relevance in decision-making in the energy sector and policy-making at a national level, considering the implications in terms of meeting the nationally determined contributions to mitigate climate change in the frame of the Treaty of Paris.
Ir al enlaceAutor(es): Daniel Verán Leigh, Gustavo Larrea Gallegos, Ian Vázquez Rowe
Purpose: Road construction and transportation generate significant environmental impacts. Hence, it is increasingly important to understand the environmental burdens produced throughout the different stages of road development: construction, maintenance, traffic, and end-of-life. In this study, life cycle assessment (LCA) was used as an environmental management methodology to determine the impacts associated with a 22.4 km stretch of the South Pan-American (PS) highway in the province of Lima, Peru, one of the main access routes for traffic and goods entering Lima, located in a hyper-arid area parallel to the Pacific Ocean. Methods: Life cycle modeling included the site-specific estimation of particulate matter emissions due to tire abrasion, brake lining, and road surface dust. In addition, different modeling options for combustion emissions for vehicles were considered. For this, sensitivity and uncertainty analysis were undertaken considering different emission standards and current vehicle fleet characteristics. The impact assessment stage included the calculation of climate change emissions, as well as air quality and abiotic depletion impact categories. Results and discussion: Results demonstrate that environmental impacts are mainly attributable to traffic, representing in all impact categories assessed over 97% of burdens. The sensitivity analysis suggests that the use of secondary data from commonly used life cycle databases is a good proxy for the estimation of global warming potential impacts in the transport sector. However, for air quality categories, important variability was detected based on modeling assumptions. Conclusions: This study intends to serve as a reference for the life cycle modeling of controlled access highways in developing countries, particularly in hyper-arid or desert areas.
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