Resumen Introducción. La valorización de los subproductos alimentarios en la alimentación animal se ha convertido en una estrategia fundamental. Este enfoque innovador no solo aborda el desafío de la gestión del desperdicio de alimentos, sino que también contribuye a la optimización de los recursos en la nutrición animal. Objetivo. Caracterizar los residuos alimentarios (residuos de melaza de algarroba, semillas de algarroba, cáscaras de naranja amarga y cáscaras de huevo de gallina color marrón) con vistas a su utilización como complemento alimenticio de valor añadido para animales, sobre la base de sus compuestos biológicamente activos. Materiales y métodos. En este estudio se utilizaron algunos subproductos alimentarios, como residuos de melaza de algarroba, cáscaras de naranja y cáscaras de huevo. El material biológico se recogió en Boumerdés, Argelia, durante el 2021, según el periodo de maduración del material vegetal (agosto para algarrobas y diciembre para naranjas). Para la caracterización de los diferentes componentes del material biológico, se utilizaron pruebas fitoquímicas basadas en reacciones colorantes, cromatografía líquida de alta resolución (HPLC, por sus siglas en inglés), espectrofotometría de absorción atómica y solubilidad en disolventes. Resultados. Se encontró que los subproductos eran bajos en grasas y proteínas, y moderadamente altos en azúcar. La piel de naranja constituye un reservorio de vitamina C, carotenoides y compuestos fenólicos. El estudio mineralógico mostró un predominio de calcio, magnesio y fósforo en la cáscara de huevo. La comparación de los subproductos mostró que las semillas de algarroba son las menos ricas en fibra bruta y, por lo tanto, aportan más carbohidratos disponibles y brindan más energía asimilable en comparación con otros subproductos. Conclusiones. Estos subproductos alimentarios proporcionan compuestos bioactivos, que incluyen vitamina C, carotenoides, compuestos fenólicos y algunos minerales, y proporcionan más energía disponible. La combinación de estos subproductos constituye un complemento alimenticio de valor añadido para la alimentación del ganado.

Abstract Introduction. The valorization of food by-products in animal feed has emerged as a pivotal strategy. This innovative approach not only addresses the challenge of food waste management but also contributes to the optimization of resources in animal nutrition. Objective. To characterize food waste (carob molasses residue, carob seeds, bitter orange peels and brown chicken eggshells) with a view to their use as a value-added food supplement for animals based on their biologically active compounds. Materials and methods. In this study, several food by-products were utilized, including carob molasses residue, orange peels and eggshells. The biological material was collected in Boumerdès, Algeria, during 2021, according to the ripening period of the plant material (August for carob and December for oranges). For the characterization of the different components of the biological material, phytochemical tests based on color reactions, high-performance liquid chromatography (HPLC), atomic absorption spectrophotometry and solubility in solvents were employed. Results. The by-products were found to be low in fat and protein, and moderately high in sugar. Orange peel constitutes a reservoir of vitamin C, carotenoids and phenolic compounds. The mineralogical study showed a predominance of calcium, magnesium and phosphorus in the eggshells. The comparison of by-products shows that carob seeds are the least rich in crude fiber and therefore supply more available carbohydrates, providing more assimilable energy compared to other by-products. Conclusions. These food by-products provide bioactive compounds, including vitamin C, carotenoids, phenolic compounds, as well as some minerals, and offer more available energy. The combination of these by-products constitutes a value-added food supplement for livestock feed.

Resumen (Introducción): El agua es esencial para todos los seres vivos, ya que facilita el transporte de nutrientes, la eliminación de desechos y la regulación de la temperatura corporal. El agua subterránea es la principal fuente para el consumo de ganado bovino y la falta de aquella de buena calidad puede impactar negativamente en su salud, reproducción y productividad. En Argentina, la ganadería bovina para la producción de carne y leche es una actividad económica clave, por lo que resulta crucial garantizar un suministro de agua adecuado en cantidad y calidad. (Objetivo): Evaluar la calidad del agua subterránea para el ganado en la cuenca lechera de Santa Fe, Argentina, utilizando un índice de calidad de agua adaptado para bovinos. (Metodología): Durante el periodo 2023-2024, se recolectaron muestras de agua subterránea en una de las principales cuencas lecheras del país. Se analizaron parámetros significativos para la calidad del agua destinada al consumo bovino, tales como pH, sólidos disueltos totales, sulfato, cloruro, nitrato y arsénico. Cada parámetro recibió una valoración basada en sus efectos perjudiciales para los animales y, mediante una ecuación matemática, se clasificó la calidad del agua desde muy buena hasta extremadamente pobre. (Resultados): El estudio reveló que un alto porcentaje de las muestras de la cuenca lechera presentan una calidad buena o muy buena, aunque también se identificaron pozos con calidad deficiente. (Conclusiones): Los resultados subrayan la importancia de monitorear y gestionar la calidad del agua subterránea, para asegurar una ganadería bovina sostenible en la cuenca lechera de Santa Fe.

Abstract (Introduction): Water is essential for all living beings as it facilitates nutrient transfer, waste elimination, and body temperature regulation. Groundwater is the primary source for bovine livestock consumption, and poor-quality water can negatively affect their health, reproduction, and productivity. In Argentina, bovine farming for meat and milk production is a significant economic activity, making it crucial to ensure an adequate supply of water in both quantity and quality. (Objective): This study aims to evaluate groundwater quality for cattle in the Santa Fe dairy basin, Argentina, using a water quality index adapted for bovines. (Methodology): During the 2023-2024 period, groundwater samples were collected from one of the main dairy basins in the country. Parameters significant to water quality for bovine consumption, such as pH, total dissolved solids, sulfate, chloride, nitrate, and arsenic, were analyzed at each monitored well. Each parameter was assigned a score based on its harmful effects on livestock, and a mathematical equation was applied to classify water quality from very good to extremely poor. (Results): The study revealed that a high percentage of samples in the dairy basin are of good or very good quality, although wells with poor water quality were also identified. (Conclusions): The findings highlight the importance of monitoring and managing groundwater quality to ensure sustainable bovine farming in the Santa Fe dairy basin.

Resumen (Introducción): La farmacontaminación es un tema que preocupa de modo creciente en el nivel mundial, y Latinoamérica no es la excepción. Sin embargo, los datos sobre este fenómeno en la región siguen siendo limitados. Este estudio aborda una de las aristas del problema: la generación y gestión de residuos de medicamentos en el ámbito sanitario. (Objetivo): Caracterizar la generación y gestión de residuos de medicamentos provenientes de instituciones sanitarias, incluyendo farmacias comunitarias, establecimientos sanitarios con y sin internación, droguerías y veterinarias. Adicionalmente, analizar la operatoria y normativa asociada a estos residuos en los entes de control de la ciudad de Neuquén, Argentina (2023). (Metodología): Estudio observacional, transversal y prospectivo. La información fue recolectada mediante encuestas validadas, aplicadas a una muestra estratificada proporcional de 114 establecimientos sanitarios, y a través de entrevistas con representantes de los entes de control. (Resultados): Todos los establecimientos cumplen con las normativas ambientales vigentes. Las droguerías presentan una mejor gestión, así que destacan en trazabilidad, estandarización y capacitación. Aunque se utiliza el control de stock, se aplican pocas estrategias secundarias para reducir residuos y existe una insuficiente valorización de materiales. Si bien hay una actitud municipal proactiva para el control del fenómeno, esta no cuenta con un respaldo efectivo de otros niveles gubernamentales. (Conclusiones): La gestión de residuos en las instituciones sanitarias estudiadas presenta oportunidades de mejora. Según las variables evaluadas, el uso de herramientas y estrategias recomendadas para la gestión de calidad es limitado. Existe un compromiso positivo en el nivel municipal, pero no se replica en todas las instancias de gobierno. Además, la percepción y visibilidad de la farmacontaminación y sus riesgos es baja entre las personas involucradas en la cadena de uso de medicamentos.

Abstract (Introduction): Pharmaceutic contamination is a growing global concern, and Latin America is no exception. However, information specific to this phenomenon in the region remains scarce. This study addresses one aspect of the problem: the generation and management of pharmaceutical waste in healthcare settings. (Objective): To characterize the generation and management of pharmaceutical waste produced by healthcare institutions, including community pharmacies, healthcare facilities with and without inpatient services, pharmaceutical distributors, and veterinary clinics. Additionally, to analyze the operations and regulations governing this waste in regulatory entities within the city of Neuquén, Argentina (2023). (Methodology): Observational, cross-sectional, and prospective study. Data collection involved validated surveys applied to a proportional stratified sample of 114 healthcare establishments and interviews with representatives of regulatory entities. (Results): All establishments comply with current environmental regulations. Pharmaceutical distributors demonstrate superior management, excelling in traceability, standardization, and training. While stock control is utilized, there are few secondary strategies to reduce waste and insufficient material recovery. Municipal initiatives and attitudes towards controlling this phenomenon are positive but lack support from higher levels of government. (Conclusions): The management of pharmaceutical waste in the healthcare institutions studied shows room for improvement. According to the variables analyzed, the use of recommended tools and strategies for quality management is limited. A positive municipal commitment to addressing the issue was identified, but this is not reflected at all governmental levels. Furthermore, the perception and awareness of pharmaceutical contamination and its risks remain low among stakeholders in the pharmaceutical use chain.

Abstract The growing generation of solid waste and the technical, operational and economic incapacity to manage it represent a challenge and a concern for local governments in Mexico, especially for the Municipality of Cuetzalan in Puebla state. This article explains the recent incorporation, in the Cuetzalan’s public agenda, of the proposal for a solid waste composting centre promoted by a group of experts linked to the National Waste Research and Advocacy Project. Findings from interviews with key informants and press releases suggest, from a public action approach, that this technical and accompaniment proposal has not materialised due to the absence of actual spaces for participation and the political-administrative interests of authorities and collectives around the proposal. The project’s decision-making process was vertical and did not promote consultation. The City Council saw society's political skills and organisational capacities as an obstacle rather than a resource.

Resumen La creciente generación de residuos sólidos y la incapacidad técnica, operativa y económica para su manejo, representan un desafío y una preocupación para los gobiernos locales en México, en especial para el Ayuntamiento de Cuetzalan, en el estado de Puebla. Este artículo explica la incorporación en la agenda pública reciente de Cuetzalan, la propuesta de un centro de compostaje de residuos sólidos promovido por un grupo de expertos vinculados al Proyecto Nacional de Investigación e Incidencia Residuos. Los hallazgos de entrevistas a informantes clave y notas de prensa sugieren que esta propuesta técnica y de acompañamiento, desde del enfoque de la acción pública, no logra concretarse debido a la ausencia de espacios reales de participación e intereses políticos-administrativos de las autoridades y colectivos alrededor de la propuesta. El proceso de toma de decisiones del proyecto fue vertical no promovió la concertación. La sociedad, con su madurez política y organizativa, fue vista por el Ayuntamiento como un obstáculo en lugar de un recurso.

Abstract Using the multilevel and multi-stakeholder governance approach, this article investigates the effective promotion of sustainable development in the Northeast of Uruguay in the departments of Tacuarembó, Rivera and Cerro Largo. This development is approached from the perspective of integrated water resources management (IWRM) and waste management (WRM), through a case study that includes participant observation and interviews with key actors within the territory. Although the three departments share a territorial and human development backlog, what really differentiates them are the weaknesses and tensions to generate agreements and resolutions, as well as the different levels of multi-stakeholder articulation with regulations, plans, public policies and the respective instances. The conclusions warn that these internal dynamics affect the response capacity and decision making of the three departments with a view to IWRM and WRM.

Resumen Empleando el enfoque de la gobernanza multinivel y multiactoral, este artículo indaga por la efectiva promoción del desarrollo sostenible en el Noreste de Uruguay, específicamente en los departamentos de Tacuarembó, Rivera y Cerro Largo. Este desarrollo se aborda desde la gestión integrada de recursos hídricos (GIRH) y de residuos (GIR), mediante un estudio de caso que incluye observación participante y entrevistas a actores clave. Aunque los tres departamentos comparten un rezago territorial y de desarrollo humano, lo que realmente los diferencia son las debilidades y tensiones para generar acuerdos y resoluciones, así como los diferentes niveles de articulación multiactoral con la normativa, los planes, las políticas públicas y las instancias respectivas. Las conclusiones advierten que estas dinámicas internas afectan la capacidad de respuesta y la toma de decisiones de los tres departamentos en relación con la GIRH y la GIR.

Abstract (Introduction): Within the framework of the present capitalist system, human beings have become an important polluting agent. Current production and consumption processes do not consider the existence of finite natural resources and a planet incapable of treating the waste that the prevailing way of life generates. Given these circumstances, the study of non-linear models is of interest, which make a more rational use of the waste that the productive activity generates, favoring recycling mechanisms. The phenomenon of recycling becomes particularly relevant in the case of electrical and electronic devices, whose ability to be degraded and metabolized by planet Earth is extremely difficult. (Objective): Evaluate the feasibility of installing and starting a recycling plant for electrical and electronics items in the town of Bahía Blanca (Argentina), during 2021. (Methodology): The conventional method for evaluating investment projects was used, considering technical, legal and economic aspects. (Results): The project is not acceptable according to the profitability intended by the investor. The possibility of financing was also included, which made the project even less profitable, and the sensitivity of the results was measured, finding that the price should be 1.48 % higher than that used in the analysis. (Conclusions): Other alternatives must be explored to make this proposal profitable from an economic and financial point of view.

Resumen (Introducción): En el marco del sistema capitalista vigente, el ser humano se ha transformado en un agente significativo de contaminación. Las dinámicas productivas y de consumo actuales no contemplan la existencia de recursos naturales finitos y de un planeta incapaz de procesar los desperdicios que el modo de vida habitual genera. Dadas estas circunstancias, cobra interés el estudio de modelos no lineales, que hagan un uso más racional de los residuos derivados de la actividad productiva, los cuales favorezcan mecanismos de reciclaje. El fenómeno del reciclaje se vuelve, en particular, relevante para el caso de los artefactos eléctricos y electrónicos; la capacidad del planeta Tierra para degradarlos y metabolizarlos resulta sumamente difícil. (Objetivo): Evaluar la factibilidad de la instalación y puesta en marcha de una planta recicladora de artículos eléctricos y electrónicos en la localidad de Bahía Blanca (Argentina), durante el 2021. (Metodología): Se utilizó la metodología convencional de evaluación de proyectos de inversión, considerando aspectos técnicos, legales y económicos. (Resultados): El proyecto no es aceptable según la rentabilidad pretendida por el inversor. También se incluyó la posibilidad de un financiamiento, lo que hizo que el plan fuera menos rentable aún, y se midió la sensibilidad de los resultados: se halló que el precio debiera ser 1.48 % superior al utilizado en el análisis. (Conclusiones): Se deben explorar otras alternativas para lograr que el proyecto sea rentable desde el punto de vista económico-financiero.

Abstract (Introduction): In the removal of chromium (VI) from tannery wastewater, physicochemical methods are the most used. However, these require high operating costs, and worse still, generate secondary pollutants that again require complementary treatments for their elimination. Given this, the applicability of vegetable organic biomass (VOB) emerges as an environmental alternative based on: the simplicity of its obtaining, the reduction as waste, it does not generate secondary pollutants and, above all, it removes chromium (VI). (Objective): Use VOB waste in an aerobic sequential biological reactor (SBR) for the removal of chromium (VI) in the treatment of tannery wastewater. (Methodology): 3 aerobic SBR systems were implemented; 2 controls (SBR1 and SBR2) and 1 study subject (SBR+VOB). Each system was fed with tannery wastewater (18 L) and connected to an aeration mechanism (12.7 L/min). The bacterial inoculum, a fundamental part of an SBR system, was gained from the selective culture of chromium (VI) reducing bacteria (RBCrVI) taken from the wastewater under study, and integrated into SBR2 and SBR+VOB at 0.6 g/L. The VOB was obtained from Stenotaphrum secundatum residues, fragmented, sieved, sterilized and integrated into the SBR+VOB at 1.5 g/L. (Results): The SBR+VOB system achieved the highest percentage of chromium (VI) removal (93 %), followed by SBR2 (80.1 %), and finally SBR1 (2.8 %). With respect to COD and TSS, the statistical test (Tukey) showed that there was no significant difference between the system under study and the controls, recording COD removal percentages ranging from 87.8 % to 88.4 %, and TSS ranging from 63.8 % to 69.2 %. (Conclusions): The viability of using VOB waste to remove chromium (VI) in the treatment of tannery wastewater has been evidenced. The results of this research create a promising panorama to mitigate the effects derived from inadequate management of tannery wastewater and organic solid waste.

Resumen (Introducción): En la remoción de cromo (VI) de aguas residuales de curtiembre, los métodos fisicoquímicos son los más empleados. Sin embargo, estos demandan altos costos operativos y, peor aún, generan contaminantes secundarios que nuevamente requieren tratamientos complementarios para su eliminación. Ante ello, la aplicabilidad de la biomasa orgánica vegetal (BOV) emerge como una alternativa ambiental sobre la base de: la simplicidad de su obtención, la disminución como residuo, no genera contaminantes secundarios y, sobre todo, de remover cromo (VI). (Objetivo): Usar residuos de BOV en un reactor biológico secuencial (RBS) aerobio, para la remoción de cromo (VI) en el tratamiento de agua residual de curtiembre. (Metodología): Se implementaron 3 sistemas RBS aerobios; 2 controles (RBS1 y RBS2) y 1 materia de estudio (RBS+BOV). Cada sistema fue alimentado con agua residual de curtiembre (18 L) y conectado a un mecanismo de aireación (12.7 L/ min). El inóculo bacteriano, parte fundamental de un sistema RBS, se obtuvo a partir del cultivo selectivo de bacterias reductoras de cromo (VI) (BRCrVI), tomadas del agua residual en estudio e integradas al RBS2 y RBS+BOV a 0.6 g/L. La BOV se obtuvo de residuos de Stenotaphrum secundatum, fragmentado, tamizado, esterilizado e integrado al RBS+BOV a 1.5 g/L. (Resultados): El sistema SRB+BOV alcanzó el mayor porcentaje de remoción de cromo (VI) (93 %), seguido por SBR2 (80.1 %) y, por último, de RBS1 (2.8 %). Con respecto a la DQO y SST, la prueba estadística (Tukey) arrojó que no había diferencia significativa entre el sistema en estudio y los controles, por lo que registró porcentajes de remoción de DQO que van de 87.8 % a 88.4 % y SST que van de 63.8 % a 69.2 %. (Conclusiones): Se ha evidenciado la viabilidad del aprovechamiento de residuos de BOV para remover cromo (VI) en el tratamiento de agua residual de curtiembre. Los resultados de la presente investigación crean un panorama prometedor para mitigar los efectos derivados de la inadecuada gestión de las aguas residuales de curtiembre y de los residuos sólidos orgánicos.

Abstract (Introduction): Sustainability evaluation has been increasingly recognized as a crucial diagnostic strategy for promoting sustainable development, particularly by addressing critical environmental concerns such as urban solid waste management in Latin American cities. Within this context, situated waste management strategies focus on promoting the valorization of recyclables as a cornerstone of the circular economy and inclusive recycling initiatives. (Objective): This study introduces a methodological framework employing a set of indicators to evaluate the valorization of recyclables across political, economic, social, and ecological dimensions of sustainability. The framework is applied specifically to Mar del Plata, Argentina, as a representative case study of an intermediate city. (Methodology): The study adopts a systemic, interdisciplinary perspective, employing a multimethod approach that integrates primary and secondary data sources. (Results): The proposed methodology considers four dimensions of sustainability and 18 indicators, each classified into three assessment levels. In Mar del Plata, the lowest scores are associated with source separation practices, the integration of waste pickers into the formal labor market, and the equitable distribution of power and control within the value chain at both local and global levels. (Conclusions): The proposed indicators offer a guide for enhancing the diagnosis and management of urban solid waste in intermediate cities, focusing on the valorization of recyclables and aligning with the Sustainable Development Goals (SDGs) at the local level.

Resumen (Introducción): La evaluación de la sustentabilidad adquiere un reconocimiento cada vez mayor como una estrategia de diagnóstico para avanzar hacia el desarrollo sustentable, pues da respuesta a preocupaciones ambientales relevantes en las ciudades latinoamericanas, como es la gestión de los residuos sólidos urbanos. En ese marco, las estrategias de gestión de residuos situadas se orientan a promover la valorización de reciclables como un eje central de la economía circular y del reciclaje inclusivo. (Objetivo): Desarrollar una propuesta metodológica de indicadores para evaluar la valorización de reciclables desde las dimensiones política, económica, social y ecológica de la sustentabilidad de manera situada en una ciudad intermedia, tomando como caso la ciudad de Mar del Plata, Argentina. (Metodología): Se asume una perspectiva sistémica, interdisciplinaria y un enfoque multimetódico sostenido en fuentes primarias y secundarias de información. (Resultados): La metodología parte de considerar cuatro dimensiones de la sustentabilidad con 18 indicadores de evaluación que contienen tres rangos. En Mar del Plata, los valores más bajos se relacionan con la separación en origen, la inserción laboral de recuperadores y el balance de poder y control en la cadena de valor locales y globales. (Conclusiones): Los indicadores propuestos constituyen una guía para profundizar en el diagnóstico y gestión de los residuos sólidos urbanos en una ciudad intermedia a partir de la valorización de reciclables, en línea con los objetivos de desarrollo sostenible previstos en la escala local.

Abstract (Introduction): The lack of feasible circular economy models for recycling single-use plastics poses a significant challenge to sustainable waste management. Single-use plastics, particularly flexible types, contribute to environmental pollution and require effective recycling strategies. (Objective): This study aimed to analyze global recycling models for single-use plastics under key parameters: type of pollutant, impacts on sustainability, value generation, stakeholders involved, and level of technology. (Methodology): A global review of 21 circular economy models focused on single-use flexible plastics was conducted, evaluating their feasibility and effectiveness. Six models were identified as the most relevant based on the selected criteria. (Results): The findings indicate that improving eco-efficiency requires the integration of physical and chemical recycling processes to achieve cost reductions. Additionally, maintaining a constant flow of recyclable materials is essential, emphasizing the critical role of material collection and classification cooperatives. In Colombia, the collection and classification of plastic materials emerged as a pivotal element for the long-term sustainability of recycling models. (Conclusions): The study highlights the necessity of combining technological and logistical efforts to enhance recycling processes. Strengthening material recovery systems and cooperative efforts is crucial for advancing circular economy goals in the context of single-use plastics.

Resumen (Introducción): La falta de modelos viables de economía circular para el reciclaje de plásticos de un solo uso representa un desafío importante para la gestión sostenible de residuos. Los plásticos de un solo uso, especialmente los tipos flexibles, contribuyen a la contaminación ambiental y requieren estrategias de reciclaje efectivas. (Objetivo): Este estudio tuvo como objetivo analizar modelos de reciclaje globales para plásticos de un solo uso bajo parámetros clave: tipo de contaminante, impactos en la sostenibilidad, generación de valor, actores involucrados y nivel de tecnología. (Metodología): Se realizó una revisión global de 21 modelos de economía circular enfocados en plásticos flexibles de un solo uso, evaluando su viabilidad y efectividad. Se identificaron 6 modelos como los más relevantes, según los criterios seleccionados. (Resultados): Los hallazgos indican que mejorar la ecoeficiencia requiere la integración de procesos de reciclaje físicos y químicos para lograr reducciones de costos. Además, es esencial mantener un flujo constante de materiales reciclables, destacando el papel crítico de las cooperativas de recolección y clasificación de materiales. En Colombia, la recolección y clasificación de materiales plásticos surgió como un elemento clave para la sostenibilidad, a largo plazo, de los modelos de reciclaje. (Conclusiones): El estudio resalta la necesidad de combinar esfuerzos tecnológicos y logísticos para mejorar los procesos de reciclaje. Fortalecer, los sistemas de recuperación de materiales y las iniciativas cooperativas, es crucial para avanzar en los objetivos de la economía circular en el contexto de los plásticos de un solo uso.

BACKGROUND. Anaesthetic drug wastage negatively impacts the already constrained economy in developing countries such as South Africa (SA). However, safe anaesthetic drug administration during both elective and emergency surgeries can be achieved without increasing wastage or costs. Drugs frequently wasted include those required in emergencies. Cost-reduction strategies, particularly in drug wastage, represent a potential area for short-term savings in hospital drug budgets. Increasing clinician awareness of drug wastage can help modify practices, leading to reduced waste while maintaining high-quality patient care. OBJECTIVE. To evaluate wastage of commonly administered anaesthetic drugs, and to evaluate preventable and routine drug wastage and its cost. METHODS. A prospective observational study was conducted in the operating theatre of Chris Hani Baragwanath Academic Hospital, a tertiary hospital in SA. Prospective data were collected for all patients who presented for elective and emergency surgical procedures at this institution over a 2-week period. Drug preparation and administration were determined by the treating anaesthesiologist. The amount of remaining drug in syringes and opened ampoules was considered as wasted. Routine drug wastage was defined as the remaining drug after the required dose was administered, while preventable drug wastage referred to drugs drawn but not administered to the patient. RESULTS. Data were collected from 373 participants, of whom 58% were undergoing elective surgery. The average drug wastage was 29.7%, comprising 21.3% routine wastage and 8.4% preventable wastage, with an effect size of 0.47 (p<0.001). Propofol accounted for the highest frequency of routine drug wastage, while preventable wastage was predominantly attributed to adrenaline, atropine and suxamethonium (emergency pharmacological agents). The average cost of routine wastage was ZAR3.85, significantly higher than the ZAR1.32 for preventable drug wastage (p<0.001). Multivariate regression analysis revealed a significant association between paediatric surgical cases and increased anaesthetic drug wastage (p=0.004). CONCLUSION. The cost and wastage of anaesthetic drugs pose significant challenges in healthcare institutions, particularly in developing countries with limited resources. Implementing cost-effective strategies, such as using smaller ampoules and prefilled syringes, has been demonstrated to reduce drug wastage without compromising patient care.

ABSTRACT Water is a vital resource for human survival, being the center of sustainable development. On the other hand, the livestock sector emerges as a major water consumer, producing a substantial volume of nutrient-rich wastewater. Consequently, the feasibility of reusing wastewater and recovering its nutrients becomes necessary to promote the sustainability of water sources. The aim of this study was to generate knowledge about tertiary treatment of wastewater from livestock and poultry industry, the reutilization of water and recovery of its nutrients, and potential applications. A systematic literature review by searching ScienceDirect and Web of Science platforms provides an exploration of technologies that facilitate the reuse of water and recovery of nutrients from livestock and poultry wastewater, including membrane filtration. As a result, the concentrated waste stream from membrane filtration can be utilized by an additional treatment of microalgae, bacteria or synergic consortia of microalgae and bacteria, in particular lactic acid bacteria that are innocuous to humans. Finally, the integration of these technologies presents a promising way to produce valuable biotechnological products with versatile applications in the pharmaceutical and food industries. However, the implementation of these technologies on an industrial scale requires more research.

The aim of this paper was to establish if mineral resource scarcity is a driver for South Africa to transition to a circular economy. The project objectives were achieved by investigating economically viable, and critical or strategic minerals remaining in South Africa, as well as resource scarcity, as a driver for South Africa to transition to a circular economy. The study found that some minerals in South Africa, such as iron ore, lead, manganese, gold, and cobalt have less than 50 years of economically viable mining remaining. At least 18 minerals can be classified indicatively as critical or strategic: aggregates, bauxite, chromite, cobalt, copper, gold, graphite, iron, limestone, lithium, manganese, nickel, phosphorous, platinum group metals, rare earth elements, silver, titanium, and vanadium. The classification was based on the minerals' economic importance, supply risk, and potential use in the development and manufacturing of emerging technologies. The findings suggest that the scarcity of mineral resources is a critical driver for the country to transition to a circular economy. Other identified drivers include socio-economic factors, climate change commitments, and business objectives. All minerals are non-renewable resources and at risk of depletion, therefore sustainable extraction and use are critical. Priority should be directed at investigating circular economy opportunities and substitutes for commodities at risk of being depleted within the next 50 years. There is an opportunity for South Africa to transition from a minerals export-based model to one that promotes local mineral beneficiation and manufacturing of end products.

Cappadocia is not only a region of Turkey with historical and touristic importance. During the cutting and processing of volcanic tuff, quarries in this region release large amounts of tuff into the environment that is viewed as waste. The release of this waste constitutes an economic loss and contributes to environmental pollution. However, through experimentation with deformation, weight per unit of volume, water absorption, uniaxial compression strength, modulus of elasticity, and point load strength index, volcanic tuff and marble dust composite materials can be produced for use in the building sector. In this study it was observed that, as the percentage of volcanic tuff dust in the mixture increased, the water absorption rate of the material increased, and uniaxial compression strength and point load strength decreased. The produced composite samples used in this study were kept for a predetermined number of times per day, and no deformation in the surface characteristics of the materials was observed. In a statistical parameter analysis, averages, variances, standard deviations, coefficients of variation, and skewness coefficients were calculated. Covariance changes between experimental parameters were also determined. In this study, two types of volcanic tuff dust, that is, yellow and red, were produced during the production of tuff-marble dust composite material. When the percentage of either type of volcanic tuff dust was increased, an increase in water absorption was observed. It was also observed that when the percentage of volcanic tuff dust was increased, uniaxial compressive strength and point load strength decreased. Furthermore, the physical and mechanical properties of the materials obtained by mixing different colored tuff powders and marble powders in different proportions were evaluated using statistical parameter analysis.

Abstract The genus Pleurotus presents a multivariate species diversity due to its ability to grow in different substrates and environments. Whether wild or cultivated, they are edible mushrooms, as they present a high nutritional value and are medicinal due to their bioactive compounds with positive health effects. The aim of this review is to highlight the importance of the genus Pleurotus, since it is a cosmopolitan mushroom, and its properties can be used in different industrial applications and be a functional alternative for our future. Due to their saprophytic nature, they produce enzymes that act on the substrate in which they grow, degrading lignocellulosic material such as wood, forest and agricultural residues, hardwoods, wood by-products, cereal straw, bagasse, etc., and thanks to this degradative capacity, their enzymes are used in a wide range of biotechnological and environmental applications. In order to increase their production and consumption not only for their nutritional qualities, but also for their nutraceutical and biotechnological qualities, ease of cultivation, low investment cost, etc., new ways are being sought to increase their performance in cultivation. Recently, research has expanded the search for alternative uses of the Pleurotus genus, which has led to an increase in its cultivation, as well as its application in different fields of biotechnology. The cultivation of Pleurotus mushrooms represents an opportunity to generate a sustainable process and incorporate the process into a circular economy, generating environmental, social and economic benefits. The use of agro-industrial substrates and the subsequent reuse of the spent substrate as compost or organic fertilizer reduces the amount of waste that ends up in landfills and minimizes methane production. This allows for a more sustainable and environmentally friendly production model. Therefore, it is necessary to develop strategies for the promotion, marketing and sustainable production of products derived from these fungi.

RESUMO A disposição de resíduos sólidos em aterros sanitários é um grande desafio para o setor de celulose e papel, e sua utilização como fertilizantes e corretivos de solo tem apresentado potencial como uma nova alternativa de destino. Assim, este trabalho objetivou identificar os fatores que influenciam esta alternativa de destinação dos resíduos e validar sua viabilidade técnica, legal e econômica através de uma revisão sistemática de literatura, de acordo com os principais itens para relatar revisões sistemáticas e meta-análises. De forma geral, foram identificados como benefícios o aumento da fertilidade e controle da acidez do solo através da aplicação de lodo de estações de tratamento de efluentes, resíduos da recuperação do licor verde e cinzas de biomassa, e os teores de metais tóxicos se mantiveram abaixo dos limites da legislação. Estes resultados, além de alavancarem ambientalmente o setor de celulose e papel pela destinação adequada de resíduos industriais, promovem a circularidade no manejo florestal e culturas agrícolas. Em relação aos aspectos econômicos, no entanto, não foram encontrados trabalhos conclusivos, sendo necessário o desenvolvimento de um estudo robusto para comprovação da viabilidade econômica desta aplicação.

ABSTRACT Industrial waste disposal in landfills is a challenge for the pulp and paper industry, and its use as fertilizers and soil conditioners has exhibited potential as a new alternative destination. As such, the present study aimed to identify factors that affect this alternative use for these residues and validate its technical, legal and economic feasibility through a systematic literature review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. In general, applying wastewater treatment plant sludge, green liquor dregs and biomass ashes in the field has been shown to increase soil fertility, control its acidity, and maintain toxic metal content within the recommended limits. This enables the environmental leveraging of the pulp and paper sector by providing an appropriate alternative destination for industrial waste and promotes circularity in forest and agricultural management. However, no conclusive studies on the economic aspects of this alternative application were found, demonstrating the importance of conducting comprehensive research to confirm its economic feasibility.