Cleotilde Anahí Álvarez Contreras

Major rivers in Veracruz show significant levels of contamination, closely linked to agro-industrial activities—particularly sugarcane cultivation—and the intensive use of fertilizers and pesticides, with implications for human health, the environment, and productive activities. In the central region of the state of Veracruz, Mexico, water quality faces increasing pressure due to the discharge of domestic and industrial wastewater, leachates from sanitary landfills, climate change, and accelerated population growth. These factors af fect water availability and compromise its safety for human consumption and environmental balance. The purpose of this research was to identify the main sources of contamination, analyze their impacts on the environment and public health, and recognize knowledge gaps to guide future research and public policies. The PRISMA 2020 methodology was applied to conduct a rigorous and replicable systematic review of the scientific literature. The search was carried out in Google Scholar, Springer, Taylor & Francis, and ScienceDirect. From 380 initial records, 30 articles that met the inclusion criteria (related to water quality, findings from similar regions, and studies in central Veracruz) were selected for detailed analysis. Using VosViewer, a bibliometric analysis was performed, identifying two major thematic axes: one ecological-geographical (ecosystem services, land use, wetlands, and regional characteristics) and another technical, focused on the evaluation and ef ficiency of treatment systems, particularly constructed wetlands. The findings show sustained growth in scientific production since 2015, reflecting increasing interest in sustainable solutions and integrated water management strategies. This study provides an updated overview of water-related challenges in Veracruz and highlights the urgency of strengthening public policies and appropriate technologies to improve water quality and protect this essential resource for life.

El poliestireno es uno de los principales plásticos desechados en el mundo. Se estima que el consumo en México de este plástico oscila las 125,000 toneladas al año. De esta cantidad menos del 0.1% logra reciclarse. El aceite de cocina usado es otro residuo que en México se genera en grandes cantidades y que no cuenta con un proceso de reciclaje establecido. Este es uno de los principales causantes de la contaminación del agua. Su disposición final en redes de drenaje y consecuentemente en cuerpos de agua propician la degradación inminente de la flora y fauna con la que entra en contacto. Este estudio demuestra la viabilidad técnica del reciclaje por densificación de residuos de polietileno utilizando aceite de cocina usado como disolvente. Para lograrlo, se siguieron sencillos pasos que constaron del acopio de los residuos, el proceso de densificación y el análisis de los resultados. Con esta alternativa de reciclaje se obtiene la disminución del volumen de los residuos de poliestireno en un 90%. También se obtiene un producto plástico recuperado propicia el estudio de usos y aplicaciones para el mismo. Este procedimiento se proyecta como una alternativa económica y ecológica en comparación con otros métodos de reciclaje de los residuos mencionados.

Recently, the excessive generation of plastic waste and its inadequate management have represented a problem worldwide. Petrochemical plastics, which account for 80% of the world's total plastic use, are the main pollutants. With the growth of the population and its needs, the generation of polystyrene waste increases considerably. Expanded polystyrene (EPS) has a very low recycling rate; it is estimated that, of 125 thousand tons generated annually in Mexico, only 0.1% is recycled. The objective of this project is to obtain a preliminary diagnosis on the generation of EPS waste in the city of Misantla, Ver., which allows its post-consumer use as recycled raw material, under a circular economy approach. The methodological proposal for the development of this research was defined in the following steps: (1) characterization of the participating actors, from the Circular Economy approach; (2) identification of businesses that generate polystyrene as waste; (3) determination of the type of polystyrene generated; (4) estimation of the quantities of waste generated; (5) analysis in comparison with the generation of other types of waste; (6) generation of post-consumer use strategies. According to the 2019 Economic Census, in Misantla the economic sector with the largest number of economic units in the municipality is retail, where it is located, the sale of food in small establishments or street stores, these agents being identified as the main generators of polystyrene waste. A survey was applied to 96 companies, mainly in the food sector. The results of these surveys show that these establishments mainly use disposable products made of expanded polystyrene such as plates and cups, and that, in some cases, the use of disposable polystyrene products such as containers and spoons was identified. With the information collected, it is concluded that the use of disposable products generates approximately 765 kilograms of EPS waste. Unlike plastic waste, misinformation about the recycling of EPS, the lack of strategies for its collection and post-consumer use, as well as the lack of awareness for its recycling, give way to it ending up in final disposal sites, continuing with the trend framed in different investigations that maintain that its final destination is incineration. After the diagnosis, there is a concrete vision of the generation of polystyrene waste and future work is given in the generation and implementation of strategies that allow the use of post-consumer unicel for its return to the value chain.