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Advances generated in medicine, science, and technology have contributed to a better quality of life in recent years; however, antimicrobial resistance has also benefited from these advances, creating various environmental and health problems. Several determinants may explain the problem of antimicrobial resistance, such as wastewater treatment plants that represent a powerful agent for the promotion of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARG), and are an important factor in mitigating the problem. This article focuses on reviewing current technologies for ARB and ARG removal treatments, which include disinfection, constructed wetlands, advanced oxidation processes (AOP), anaerobic, aerobic, or combined treatments, and nanomaterial-based treatments. Some of these technologies are highly intensive, such as AOP; however, other technologies require long treatment times or high doses of oxidizing agents. From this review, it can be concluded that treatment technologies must be significantly enhanced before the environmental and heath problems associated with antimicrobial resistance can be effectively solved. In either case, it is necessary to achieve total removal of bacteria and genes to avoid the possibility of regrowth given by the favorable environmental conditions at treatment plant facilities.

Pollution of aquatic ecosystems due to toxic mixtures is a worldwide problem associated with the increase of wastewater discharges that causes problems to human health and biodiversity. This study aims to evaluate the cytotoxic potential of water from the Atoyac River. Meristems of Allium cepa L. were exposed to water samples from the Atoyac River with different concentrations for 120 hours. Pearson correlation was used to investigate the relationship between contaminants and cytotoxicity. The results corroborated the cytotoxic effect of the mixture of agents such as toxic metals and volatile organic compounds found in all river sampling sites. The Allium cepa test showed decreased mitotic alterations in prophase and metaphase indices. There was a strong negative association between the concentration of toxic metals and volatile organic compounds and the cytotoxic effect. The observations of cytotoxic effects show that the contaminant mixture contains aneugenic agents which prevent the synthesis and fixation of fibers of the mitotic spindle to the kinetochore, which prevents the displacement of the chromosomes. This study shows the need to study the effects at the cellular and molecular level in heavily polluted rivers to prevent negative effects on exposed ecosystems and populations.

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La determinación de cambios en la cubierta terrestre (CT) es importante para entender la dinámica de los ecosistemas. En este estudio se analizaron los cambios espaciales y temporales en el municipio de Ixtacamaxtitlán, Puebla durante el periodo 2000-2015, utilizando los mapas globales de la Agencia Espacial Europea ESA-CCI-LC. Para ello, se determinó la matriz de cambios, la tasa anual de cambio y la probabilidad de permanencia, así como la precisión del mapa de CT 2015. Los resultados indican que las pérdidas se concentraron en las coberturas arboladas y pastizales (0.27% y 8.83%, respectivamente), mientras que las ganancias se dieron en tierras de cultivo y zonas urbanas (6.9% y 8.11%, respectivamente). La mayoría de los cambios se observaron en las zonas de fácil acceso ubicadas en la porción centro-norte del municipio. De las 1962 ha que presentaron cambios entre categorías, en 87.4% el cambio fue negativo y en 12.6% fue positivo, destacando la transición de pastizales y superficies arboladas hacia tierras de cultivo, causadas por diversos procesos socioeconómicos presentes en la zona como marginación, migración, acceso a programas gubernamentales, expansión de áreas agrícolas y diversificación de cultivo. El mapa de CT 2015 mostró una alta precisión a escala subnacional (85.64%) lo que revela que este conjunto de datos es confiable para el estudio de las transformaciones en el territorio.