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Husks of rice (RH), coffee (CH), and cholupa (CLH) were used to produce natural adsorbents. The natural adsorbents were used to remove pharmaceuticals such as diclofenac, ciprofloxacin, and acetaminophen in a mixture of distilled water. However, CH stood out for its efficiency in removing ciprofloxacin (74%) due to the higher concentration of acidic groups, as indicated by the Boehm method. In addition, CH removed 86% of ciprofloxacin individually. Therefore, CH was selected and used to remove other fluoroquinolones, such as levofloxacin and Norfloxacin. Although electrostatic interactions favored removals, better removal was observed for ciprofloxacin due to its smaller molecular volume. Then, ciprofloxacin was selected, and the effect of pH, matrix, and adsorbent doses were evaluated. In this way, using a pH of 6.2 in urine with a dose of 1.5 g L-1, it is possible to adsorb CIP concentrations in the range (0.0050-0.42 mmol L-1). Subsequently, the high R2 values and low percentages of APE and Δq indicated better fits for pseudo-second-order kinetics, suggesting a two-stage adsorption. At the same time, the Langmuir isotherm recommends a monolayer adsorption with a Qm of 25.2 mg g-1. In addition, a cost of 0.373 USD/g CIP was estimated for the process, where the material can be reused up to 4 times with a CIP removal in the urine of 51%. Consequently, thermodynamics analysis showed an exothermic and spontaneous process with high disorder. Furthermore, changes in FTIR analysis after adsorption suggest that CH in removing CIP in urine involves electrostatic attractions, hydrogen bonds and π-π interactions. In addition, the life cycle analysis presents, for the 11 categories evaluated, a lower environmental impact of the CIP removal in urine with CH than for the preparation of adsorbent, confirming that the adsorption process is more environmentally friendly than materials synthesis or other alternatives of treatments. Furthermore, future directions of the study based on real applications were proposed.

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In order to analyze the environmental performance of Smallholder Dairy Farms (SHDFs) located in the State of Mexico, a Life Cycle Analysis (LCA) was carried out using two methodological approaches (A1 and A2) to estimate and interpret environmental impacts. A1 consisted in obtaining the average inputs and outputs of 15 SHDFs to generate a representative farm life cycle inventory, while A2 included an individual environmental impact analysis per SHDF to obtain average values of the contributions per analyzed midpoint impact category. The feed production subsystem generated the highest contributions to environmental impacts per liter of raw milk produced. Estimated emissions based on A2 approach, resulted in higher environmental impacts compared to results obtained with A1. The estimated values for the midpoint impact categories obtained with A2: Climate change, Fossil depletion, Terrestrial acidification, and Agricultural land occupation, were 8.73%, 30.77%, 100%, and 20.49% higher compared to A1 approach, respectively. While A2 provides more accurate results, it requires more time and resources compared to the integration of a panel of representative dairy farms.

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Brazil is the second-largest ethanol producer in the world, primarily using sugar cane as feedstock. To foster biofuel production, the Brazilian government implemented a national biofuel policy, known as RenovaBio, in which greenhouse gas (GHG) emission reduction credits are provided to biofuel producers based on the carbon intensities (CI) of the fuels they produce. In this study, we configured the GREET model to evaluate life cycle GHG emissions of Brazilian sugar cane ethanol, using data from 67 individual sugar cane mills submitted to RenovaBio in 2019/2020. The average CI per megajoule of sugar cane ethanol produced in Brazil for use in the U.S. was estimated to be 35.2 g of CO2 equivalent, a 62% reduction from U.S. petroleum gasoline blendstock without considering the impacts of land use change. The three major GHG sources were on-field N2O emissions (24.3%), sugar cane farming energy use (24.2%), and sugar cane ethanol transport (19.3%). With the probability density functions for key input parameters derived from individual mill data, we performed stochastic simulations with the GREET model to estimate the variations in sugar cane ethanol CI and confirmed that despite the larger variations in sugar cane ethanol CI, the fuel provided a robust GHG reduction benefit compared to gasoline blendstock.

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The textile industry is known for its large consumption of water, energy, and chemical products, making it one of the most environmentally impactful activities. To measure these environmental impacts, life cycle analysis (LCA) is a powerful tool that considers the entire process, from the extraction of raw materials to the finalization of textile products. In this context, this work aimed to present a systematic study on the use of the LCA methodology in the environmental assessment of effluents from the textile industry. The survey for data was carried out using the Scopus and Web of Science databases, and the PRISMA method was utilized for organizing and selecting of articles. During the meta-analysis phase bibliometric and specific data were extracted from selected publications. For the bibliometric analysis, a quali-quantitative approach was adopted, and the VOSviewer software was employed. The review encompasses a total of 29 articles, which were published between 1996 and 2023.The majority of the reviewed articles have shown the use of the LCA as a supportive tool for optimization focusing on sustainability, comparing the environmental, economic, and technical aspects through different approaches. The findings revel that China has the highest number of authors among the selected articles, while researchers from France and Italy had the highest number of international collaborations. The ReCiPe and CML methods were the most frequently used for evaluating life cycle inventories, with global warming, terrestrial acidification, ecotoxicity, and ozone depletion being the main impact categories. The use of activated carbon in textile effluents treatment has shown to be promising since it is environmentally friendly.

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Despite the structural and electrochemical advantages of LiFePO4 (LFP) as a cathode material, the solid-state reaction commonly used as a method to produce it at the industrial level has known disadvantages associated with high energy and fossil fuel consumption. On the other hand, solution-based synthesis methods present a more efficient way to produce LFP and have advantages such as controlled crystal growth, homogeneous morphology, and better control of pollutant emissions because the reaction occurs within a closed system. From an environmental point of view, different impacts associated with each synthesis method have not been studied extensively. The use of less polluting precursors during synthesis, as well as efficient use of energy and water, can provide new insights into the advantages of each cathode material for more environmentally friendly batteries. In this work, a solvothermal method is compared to a solid-state synthesis method commonly used to elaborate LFPs at the commercial level in order to evaluate differences in the environmental impacts of both processes. The solvothermal method used was developed considering the reutilization of solvent, water reflux, and a low thermal treatment to reduce pollutant emissions. As a result, a single high crystallinity olivine phase LFP was successfully synthesized. The use of ethylene glycol (EG) as a reaction medium enabled the formation of crystalline LFP at a low temperature (600 °C) with a nano-plate-like shape. The developed synthesis method was evaluated using life cycle analysis (LCA) to compare its environmental impact against the conventional production method. LCA demonstrated that the alternative green synthesis process represents 60% and 45% of the Resource Depletion impact category (water and fossil fuels, respectively) of the conventional method. At the same time, in the Climate change and Particular matter impact categories, the values correspond to 49 and 38% of the conventional method, respectively.

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Avocado consumption and trade are increasing worldwide, with North America and Europe being the main importing regions. Spain is the major European avocado producer (90% of the production), yet it only supplies 10% of the market. Consequently, more than 90% of the avocados consumed in Europe are imported from overseas, mainly from Chile and Peru. In this work, the Life Cycle Assessment (LCA) impact associated with the transport of two avocado supply chains (short (Spanish) and long (Chilean)) and the effect of the fruit origin and distance of both chains on primary and secondary metabolites from harvest to edible ripeness were evaluated using a gas chromatography-mass spectrometry (GC-MS) and liquid chromatography coupled to diode array detection (LC-DAD) based metabolite analysis. The LCA transport impact of the fresh supply chain from production centers in Chile (Quillota) and Spain (Malaga), and then the distribution to several cities in Europe, suggested road export from Spain to European capitals to have the lowest impact (0.14 to 0.22 kg CO2 eq/kg of avocado). When export from Chile was considered, the option of oceanic freight to European ports closer to final destinations was clearly a better option (0.21 to 0.26 kg CO2 eq/kg) than via the Algeciras port in Spain followed by road transport to final destinations in European capitals (0.34 to 0.43 kg CO2 eq/kg), although the situation could be somewhat different if the avocados are transported from the destination ports in northern Europe to long-distance capitals in other European countries. Fruit origin had a significant impact on avocado primary and secondary metabolites. The conditions of the supply chain itself (10 d in cold storage in regular conditions vs. 30 d cold storage + controlled atmosphere conditions) largely influence the fate of some metabolites that certainly affect the pool of metabolites at edible ripeness. The long-assumed hypothesis that the longer the supply chain the more negative impact on nutritional and functional compounds might not hold in this case, as long as transport conditions are adequate in terms of temperature, atmosphere conditions, and time considering distance from origin to destination.

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In the present research work, the use of agro-industrial waste such as agave bagasse from the tequila industry was carried out. The agave bagasse was treated to obtain biosorbent and hydrochar materials. Direct Blue 86 was used as an adsorbate model to evaluate the performance of both materials. The adsorption studies showed an adsorption capacity of 6.49 mg g−1 in static and 17.7 mg g−1 in dynamic, associated with a physisorption process between functional groups of the material and the dye. The characterization of the biosorbent showed that the material was mainly composed of macroporous fibers with a surface area <5.0 m2 g−1. Elemental analysis showed a majority composition of C (57.19 wt%) and O (37.49 wt%). FTIR and XPS analyses showed that the material had C-O, C=O, -OH, O-C=O, and -NH2 surface groups. RAMAN and TGA were used to evaluate the composition, being cellulose (40.94%), lignin (20.15%), and hemicellulose (3.35%). Finally, the life-cycle assessment at a laboratory scale showed that the proposed biosorbent presents a 17% reduction in several environmental aspects compared to hydrochar, showing promise as an eco-friendly and highly efficient method for the remediation of water contaminated with dye, as well as being a promising alternative for the responsible management of solid waste generated by the tequila industry.

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Food consumption and production plays a major role on human health and environmental sustainability. In addition, socio-economic status (SES) could be an important determinant on these impacts. Here we investigated the quality and environmental footprints of diets of different SES in Argentina. Dietary data was obtained from a recent national-wide representative survey (21,547 households), and individual intake was estimated by applying the Adult-Male Equivalent (AME) approach. Dietary quality was assessed by comparing the apparent consumption of foods and nutrients with the level of intake associated with the lowest risk of mortality, and applying the Alternate Healthy Eating Index 2010 (AHEI-2010). The environmental footprints were assessed with a set of six environmental indicators: greenhouse gas (GHG) emissions, total land occupation, cropland demand, fossil energy use, freshwater consumption and eutrophying emissions. Per capita total expenditure was utilized as an indicator of SES. We found a suboptimal intake of healthy and excess of unhealthy foods and nutrients in all SES, as well as a low AHEI-2010 score (34.7 ± 3.56 over 100). Regarding environmental footprints per AME, we estimated 8.91 ± 2.49 kg CO2-eq/day for GHG emissions, 9.30 ± 2.93 MJ/day for fossil energy use, 54.2 ± 14.8 m2/day for total land occupation, 7.07 ± 1.90 m2/day for cropland demand, 205 ± 65.3 L/day for freshwater consumption and 19.8 ± 6.43 g PO4-eq/day for eutrophying emissions. The Argentinian diet was found to be both unhealthy and unsustainable in all socio-economic levels.

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Nanotechnology is one of the most relevant scientific areas today due to its multiple applications in fields such as medicine, environmental remediation, information technology and energy conversion. This importance has led to the need to advance in the development of environmentally sustainable and safe nanomaterials by incorporating the principles of green chemistry during their synthesis and in their applications. However, this qualitative framework of thought does not offer minimum criteria for the use of the term "green", and therefore, this adjective is commonly used to refer to bio-based or nanotechnological processes without taking into account their net ecological impact. In this context, environmental sustainability metrics can be applied to nanotechnology to compare, optimize and quantify the environmental sustainability of synthesis procedures. This review provides an overview of green chemistry and its application in nanotechnology, but also an analysis of the use of green chemistry principles in the development of bio-based nanobiotechnology and nanosynthesis, with special emphasis on the use of sustainability's metrics for the quantitative analysis of nanomaterial synthesis protocols. These include: Atom Economy, E-factor, Process Mass Intensity, Energy Intensity, and Life Cycle Analysis.

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This study reports on a Life Cycle Assessment (LCA) comparison between two different Construction and Demolition Waste (CDW) management strategies to produce Recycled Coarse Aggregate (RCA): the current recycling strategy (RCA-C) versus air jig strategy (RCA-PR). Additionally, RCAs are compared to natural aggregate production. Air jig is proposed as a recycling strategy for CDW sustainable reuse and recycling. In contrast to RCA-C, air jig allows better CDW segregation, providing recycled materials with better quality. The results point out that recycling strategies differ in segregation efficiency, the quality of recycled material produced, and environmental performance. Both recycling strategies provided environmental benefits when compared to natural aggregate. RCA-PR presents better environmental performance due to the larger number of by-products generated as a result of using air jig and it is able to reduce the environmental impacts related to its management based on the benefits of its by-products. The results suggest that the production and transport of RCA are viable from an environmental point of view in larger urban centers. This study provides a better understanding of CDW management, enhancing knowledge on the environmental performance of the current practice and a future proposal recycling strategy. Moreover, it opens up a new perspective on the multifunctionality associated with recycling strategies of CDW and understanding about air jig environmental impacts.

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In Ecuador, the net energy contribution of biofuels is unknown or unnoticed. To address this issue, we determined the Energy Return on Investment (EROI) for bioethanol and biodiesel. The selection of raw materials relied on their productive capacity, export and import records, and historical yields. Consequently, the scope included three raw materials for ethanol (sugar cane, corn, and forest residues) and four for biodiesel (African palm, pinion, bovine fat, and swine fat). Using a method based on the Life Cycle Analysis (LCA) of each biofuel, we assessed the entire production chain through statistical processing of primary and secondary information. Then we calculated the calorific values in the laboratory, compared energy inputs/outputs, and finally obtained the energetic returns. EROIs for bioethanol were: 1.797 for sugarcane, 1.040 for corn, and 0.739 for wood. The results for biodiesel were: 3.052 for African palm, 2.743 for pinion, 2.187 for bovine fat, and 2.891 for swine fat. These values suggest feasibility only for sugarcane in the case of ethanol. In contrast, biodiesel has better prospects because all the feedstocks analyzed had EROIs higher than two. Nevertheless, biodiesel is not available for trading in Ecuador because energy policy has overlooked systems based on higher energy return. Future studies should consider more comprehensive variables such as climate change, land use, and water management.

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A life-cycle assessment was conducted during semi-intensive and super-intensive commercial cultivation of marine shrimp from December 2011 to June 2012, considering all phases from the preparation of the nursery to harvesting of the shrimp, to determine the carbon footprints of each process. Inputs and outputs associated to the production of 1 kg of shrimp were evaluated using the CML-1A baseline method, V3.01 EU25, with Software SimaPro® 8.0.2, to identify the factors of impact that are most relevant to the category global warming, measured in kg of CO2 eq. The grow-out phase contributed the most to the final results in super-intensive culture, which had a higher carbon footprint, 47.9967 kg of CO2 eq., which was 1.0042 kg of CO2 eq. in the semi-intensive culture. The most important impacting factor is the use of electrical energy, which is required to maintain dissolved oxygen and the biofloc particles in suspension in the super-intensive culture and for movement of large volumes of water in the semi-intensive system.(AU)

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Dioecy has a demographic disadvantage compared with hermaphroditism: only about half of reproductive adults produce seeds. Dioecious species must therefore have fitness advantages to compensate for this cost through increased survival, growth, and/or reproduction. We used a full life cycle approach to quantify the demographic costs and benefits associated with dioecy while controlling for demographic differences between dioecious and hermaphroditic species related to other functional traits. The advantage of this novel approach is that we can focus on the effect of breeding system across a diverse tree community. We built a composite integral projection model for hermaphroditic and dioecious tree populations from Barro Colorado Island, Panama, using long-term demographic and newly collected reproductive data. Integration of all costs and benefits showed that compensation was realized through increased seed production, resulting in no net costs of dioecy. Compensation was also facilitated by the low contribution of reproduction to population growth. Estimated positive effects of dioecy on tree growth and survival were small and insignificant for population growth rates. Our model revealed that, for long-lived organisms, the cost of having males is smaller than generally expected. Hence, little compensation is required for dioecious species to maintain population growth rates similar to those of hermaphroditic species.

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We evaluated the productive chain of fish consumed in the State of Bahia using Life Cycle Analysis (LCA). We estimated the inputs and outputs from logistics and fish processing. For every kg of processed and transported fish we calculated the Global Warming Potential (GWP) based on the amount of Greenhouse Gases (GHG) given in kg of CO2eq, as follows: 0.020 electricity; 0.003 water consumption; 0.002 wastewater; 0.160 and 1.495 waste from the gutted and filleted fish, respectively; 0.871 and 1.007 refrigerated transportation of gutted and filleted fish, respectively. The sum of GHG emissions were 1.058 and 2.592 kg of CO2eq per kg of gutted and filleted fish, respectively. LCA results indicate that it is possible to reduce the GWP associated with refrigerated transportation by increasing local fish production and decreasing importation, especially given the available water potential of Bahia. However, to achieve a sustainable production it is imperative to adopt and also develop technologies that promote environmental impact reduction from solid residues.

Avaliamos a cadeia produtiva do pescado consumido no Estado da Bahia utilizando a Análise de Ciclo de Vida (ACV). Estimamos os consumos e emissões associados à logística e ao processamento do peixe. O Potencial de Aquecimento Global (PAG) foi calculado com base na quantidade de Gases Efeito Estufa (GEE) indicadas por kg de CO2eq para cada kg de peixe processado foram: 0,020 - eletricidade; 0,003 consumo de água; 0,0029 efluentes; 0,160 e 1,495 resíduos sólidos para os peixes eviscerados e filetados, respectivamente, e 0,871 e 1,007 transporte refrigerado dos peixes eviscerados e filetados, respectivamente. O somatório do impacto das emissões de GEE foram 1,058 e 2,529 kg de CO2eq por kg de peixe eviscerado e filetado, respectivamente. Os resultados indicaram que é possível reduzir o PAG do transporte refrigerado com o aumento da produção local de peixe e redução das importações, especialmente considerando o potencial hídrico da Bahia. Entretanto, a produção sustentável requer a adoção e desenvolvimento de tecnologias para reduzir os impactos ambientais do tratamento dos resíduos sólidos da etapa de processamento.

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We evaluated the productive chain of fish consumed in the State of Bahia using Life Cycle Analysis (LCA). We estimated the inputs and outputs from logistics and fish processing. For every kg of processed and transported fish we calculated the Global Warming Potential (GWP) based on the amount of Greenhouse Gases (GHG) given in kg of CO2eq, as follows: 0.020 electricity; 0.003 water consumption; 0.002 wastewater; 0.160 and 1.495 waste from the gutted and filleted fish, respectively; 0.871 and 1.007 refrigerated transportation of gutted and filleted fish, respectively. The sum of GHG emissions were 1.058 and 2.592 kg of CO2eq per kg of gutted and filleted fish, respectively. LCA results indicate that it is possible to reduce the GWP associated with refrigerated transportation by increasing local fish production and decreasing importation, especially given the available water potential of Bahia. However, to achieve a sustainable production it is imperative to adopt and also develop technologies that promote environmental impact reduction from solid residues.(AU)

Avaliamos a cadeia produtiva do pescado consumido no Estado da Bahia utilizando a Análise de Ciclo de Vida (ACV). Estimamos os consumos e emissões associados à logística e ao processamento do peixe. O Potencial de Aquecimento Global (PAG) foi calculado com base na quantidade de Gases Efeito Estufa (GEE) indicadas por kg de CO2eq para cada kg de peixe processado foram: 0,020 - eletricidade; 0,003 consumo de água; 0,0029 efluentes; 0,160 e 1,495 resíduos sólidos para os peixes eviscerados e filetados, respectivamente, e 0,871 e 1,007 transporte refrigerado dos peixes eviscerados e filetados, respectivamente. O somatório do impacto das emissões de GEE foram 1,058 e 2,529 kg de CO2eq por kg de peixe eviscerado e filetado, respectivamente. Os resultados indicaram que é possível reduzir o PAG do transporte refrigerado com o aumento da produção local de peixe e redução das importações, especialmente considerando o potencial hídrico da Bahia. Entretanto, a produção sustentável requer a adoção e desenvolvimento de tecnologias para reduzir os impactos ambientais do tratamento dos resíduos sólidos da etapa de processamento.(AU)

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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.

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