RESUMEN
The combination of silica nanoparticles with fluorescent molecularly imprinted polymers (Si-FMIPs) prepared by a one-pot sol-gel synthesis method to act as chemical sensors for the selective and sensitive determination of captopril is described. Several analytical parameters were optimized, including reagent ratio, solvent, concentration of Si-FMIP solutions, and contact time. Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and the ninhydrin assay were used for characterization. The selectivity was evaluated against molecules belonging to other drug classes, such as fluoroquinolones, nonacid nonopioids, benzothiadiazine, alpha amino acids, and nitroimidazoles. Under optimized conditions, the Si-FMIP-based sensor exhibited a working range of 1-15 µM, with a limit of detection (LOD) of 0.7 µM, repeatability of 6.4% (n = 10), and suitable recovery values at three concentration levels (98.5% (1.5 µM), 99.9% (3.5 µM), and 99.2% (7.5 µM)) for wastewater samples. The sensor provided a working range of 0.5-15 µM for synthetic urine samples, with an LOD of 0.4 µM and a repeatability of 7.4% (n = 10) and recovery values of 93.7%, 92.9%, and 98.0% for 1.0 µM, 3.5 µM, and 10 µM, respectively. In conclusion, our single-vessel synthesis approach for Si-FMIPs proved to be highly effective for the selective determination of captopril in wastewater and synthetic urine samples.
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Captopril , Límite de Detección , Nanopartículas , Aguas Residuales , Captopril/orina , Captopril/análisis , Captopril/química , Aguas Residuales/análisis , Nanopartículas/química , Polímeros Impresos Molecularmente/química , Colorantes Fluorescentes/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/orina , Dióxido de Silicio/química , Impresión Molecular , HumanosRESUMEN
Z-drugs, benzodiazepines and ketamine are classes of psychotropic drugs prescribed for treating anxiety, sleep disorders and depression with known side effects including an elevated risk of addiction and substance misuse. These drugs have a strong potential for misuse, which has escalated over the years and was hypothesized here to have been exacerbated during the COVID-19 pandemic. Wastewater-based epidemiology (WBE) constitutes a fast, easy, and relatively inexpensive approach to epidemiological surveys for understanding the incidence and frequency of uses of these drugs. In this study, we analyzed wastewater (n = 376) from 50 cities across the United States and Mexico from July to October 2020 to estimate drug use rates during a pandemic event. Both time and flow proportional composite and grab samples of untreated municipal wastewater were analyzed using solid-phase extraction followed by liquid chromatography-tandem mass spectrometry to determine loadings of alprazolam, clonazepam, diazepam, ketamine, lorazepam, nordiazepam, temazepam, zolpidem, and zaleplon in raw wastewater. Simultaneously, prescription data of the aforementioned drugs were extracted from the Medicaid database from 2019 to 2021. Results showed high detection frequencies of ketamine (90 %), lorazepam (87 %), clonazepam (76 %) and temazepam (73 %) across both Mexico and United States and comparatively lower detection frequencies for zaleplon (22 %), zolpidem (9 %), nordiazepam (<1 %), diazepam (<1 %), and alprazolam (<1 %) during the pandemic. Average mass consumption rates, estimated using WBE and reported in units of mg/day/1000 persons, ranged between 62 (temazepam) and 1100 (clonazepam) in the United States. Results obtained from the Medicaid database also showed a significant change (p < 0.05) in the prescription volume between the first quarter of 2019 (before the pandemic) and the first quarter of 2021 (pandemic event) for alprazolam, clonazepam and lorazepam. Study results include the first detections of zaleplon and zolpidem in wastewater from North America.
Asunto(s)
COVID-19 , Ketamina , Humanos , Estados Unidos/epidemiología , Benzodiazepinas , Alprazolam/análisis , Aguas Residuales/análisis , Pandemias , Nordazepam/análisis , Zolpidem/análisis , Clonazepam/análisis , Lorazepam/análisis , Espectrometría de Masas en Tándem/métodos , COVID-19/epidemiología , Temazepam/análisis , México/epidemiología , DiazepamRESUMEN
Water stress is a current environmental menace mainly driven by over exploitation of aquifers, which is triggering poor water quality with high concentration of minerals in extracted groundwater. Particularly, silica is widespread in natural water supplies due to weathering processes of silicates occurring in contact with water, light, air, and other factors. However, due to groundwater over extraction the concentration of silica has increased during the last years in aquifer reservoirs from Aguascalientes State (México). In this context, it is very important to note that the removal of silica compounds from water is challenging and different methods can be used to avoid embedding problems in different industries. In the present work, the removal of reactive silica from synthetic solutions as well as from real wastewaters from an industrial anodizing process was studied using adsorption and chemical precipitation methods. Twelve commercial materials of different nature were used for adsorption tests, while seven precipitant agents were applied in the precipitation experiments. Adsorption tests were performed in batch systems with constant stirring at 30 °C and at different pH values (7 and 9). Precipitation experiments were carried out in batch systems and the best conditions for silica removal were found using an L9 orthogonal array of the Taguchi method employing molar ratio, pH of wastewater, stirring time and temperature as experimental factors. Adsorption results showed that Ferrolox (Iron (III) hydroxide-base adsorbent) was the most efficient sorbent for reactive silica removal from synthetic solutions and the anodizing wastewater. Also, the reactive silica adsorption was higher at pH 9 as compared to that measured at pH 7 and the adsorbed quantity at pH 9 was 16.22 and 11.25 mg/g for the synthetic solution and anodizing wastewater, respectively. According to molecular simulation, the main interaction between Ferrolox and silica species was related to the formation of hydroxo-complexes and to the interaction of Fe with oxygen of silica species. Additionally, magnesium chloride was the best precipitating reagent for reactive silica achieving up to 87% removal. According to ANOVA analysis of Taguchi method, pH was the most influential factor during the precipitation of reactive silica with a variance value of 81.42, while values lower than 3 were obtained for the rest of parameters. Overall, the present work is reporting for the first time the removal of reactive silica from anodizing wastewaters with promising results that can be implemented at full scale for water reclamation, which may significantly contribute to manage water reservoir in the region sustainably.
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Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Aguas Residuales/análisis , Purificación del Agua/métodos , Dióxido de Silicio/química , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
Wastewater treatment plants (WWTPs) are recognized as important sources of Antibiotic Resistant Bacteria (ARBs) and Antibiotic Resistant Genes (ARGs), and might play a role in the removal and dissemination of antimicrobial resistance (AMR) in the environment. Detailed information about AMR removal by the different treatment technologies commonly applied in urban WWTPs is needed. This study investigated the occurrence, removal and characterization of ARBs in WWTPs employing different technologies: WWTP-A (conventional activated sludge-CAS), WWTP-B (UASB reactor followed by biological trickling filter) and WWTP-C (modified activated sludge followed by UV disinfection-MAS/UV). Samples of raw sewage (RI) and treated effluent (TE) were collected and, through the cultivation-based method using 11 antibiotics, the antibiotic resistance profiles were characterized in a one-year period. MAS was effective in reducing ARB counts (2 to 3 log units), compared to CAS (1 log unit) and UASB/BTF (0.5 log unit). The composition of cultivable ARB differed between RI and TE samples. Escherichia was predominant in RI (56/118); whilst in TE Escherichia (31/118) was followed by Bacillus (22/118), Shigella (14/118) and Enterococcus (14/118). Most of the isolates identified (370/394) harboured at least two ARGs and in over 80 % of the isolates, 4 or more ARG (int1, blaTEM, TetA, sul1 and qnrB) were detected. A reduction in the resistance prevalence was observed in effluents after CAS and MAS processes; whilst a slight increase was observed in treated effluents from UASB/BTF and after UV disinfection stage. The multi-drug resistance (MDR) phenotype was attributed to 84.3 % of the isolates from RI (27/32) and 63.6 % from TE (21/33) samples and 52.3 % of the isolates (34/65) were resistant to carbapenems (imipenem, meropenem, ertapenem). The results indicate that treated effluents are still a source for MDR bacteria and ARGs dissemination to aquatic environments. The importance of biological sewage treatment was reinforced by the significant reductions in ARB counts observed. However, implementation of additional treatments is needed to mitigate MDR bacteria release into the environment.
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Aguas del Alcantarillado , Purificación del Agua , Aguas del Alcantarillado/microbiología , Antagonistas de Receptores de Angiotensina/farmacología , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Brasil , Genes Bacterianos , Antibacterianos/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Bacterias/genética , Farmacorresistencia Bacteriana MúltipleRESUMEN
A nivel mundial, el 44% de las aguas residuales domésticas no se tratan de forma segura, la recolección y tratamiento de aguas residuales, se ha convertido en un desafío, particularmente en áreas urbanas de bajos ingresos dentro de los países en desarrollo, donde las aguas residuales pueden fluir sin tratar a transportes de aguas pluviales o canales de drenaje informales. No es raro encontrar efluentes, desechos sólidos, excretas humanas y descargas líquidas de industrias y hospitales en las aguas superficiales de muchas zonas urbanas de los países en desarrollo. El proceso de tratamiento de aguas residuales puede ser llevado en lagunas mediante reacciones tanto oxidativas como reductoras. En la capa superior de la laguna, donde las aguas residuales son aeróbicas, ocurre el mecanismo convencional de la demanda bioquímica de oxígeno aeróbico (DBO) y se produce la oxidación del amoníaco. La capa inferior de la laguna es anaerobia, y en esta zona tiene lugar la digestión de los sólidos del lodo, un intermedio, la zona facultativa permite la respiración con aceptores de electrones terminales distintos del oxígeno, esto permite reacciones como la desnitrificación. Los gases producidos en las zonas inferiores se estabilizan en la zona aeróbica por disolución oxígeno, y esto reduce los problemas de olores. Este estudio tiene como objetivo, estudiar el descenso de coliformes fecales en lagunas aireadas de plantas de tratamiento de aguas residuales en la ciudad de Lima, Perú. Los resultados señalan que la separación diferencial de las aguas tratadas, experimentó un descenso del 13 al 26% de coleiformes fecales en todas las lagunas de tratamiento(AU)
Globally, 44% of domestic wastewater is not treated safely, and wastewater collection and treatment has become a challenge, particularly in low-income urban areas within developing countries, where wastewater may flow untreated into stormwater conveyances or informal drainage channels. It is not uncommon to find effluents, solid wastes, human excreta, and liquid discharges from industries and hospitals in the surface waters of many urban areas in developing countries. The wastewater treatment process can be carried out in lagoons through both oxidative and reductive reactions. In the upper layer of the lagoon, where the wastewater is aerobic, the conventional mechanism of aerobic biochemical oxygen demand (BOD) occurs and ammonia oxidation occurs. The lower layer of the lagoon is anaerobic, and in this zone the digestion of the sludge solids takes place, an intermediate, the facultative zone allows respiration with terminal electron acceptors other than oxygen, and this allows reactions such as denitrification. The gases produced in the lower zones are stabilized in the aerobic zone by dissolving oxygen, and this reduces odor problems. The objective of this study is to study the decrease of fecal coliforms in aerated lagoons of wastewater treatment plants in the city of Lima, Peru. The results indicate that the differential separation of the treated waters experienced a decrease from 13 to 26% of fecal coleiforms in all treatment lagoons(AU)
Asunto(s)
Aguas Residuales/análisis , PerúRESUMEN
There are several techniques for the removal of pharmaceuticals (drugs) from wastewater; however, strengths and weaknesses have been observed in their elimination processes that limit their applicability. Therefore, we aimed to evaluate the best techniques for the removal of pharmaceuticals from municipal and hospital wastewater. For this, a non-experimental, descriptive, qualitative-quantitative design was used, corresponding to a systematic review without meta-analysis. Based on established inclusion and exclusion criteria, 31 open-access articles were selected from the Scopus, ProQuest, EBSCOhost, and ScienceDirect databases. The results showed that high concentrations of analgesics such as naproxen (1.37 mg/L) and antibiotics such as norfloxacin (0.561 mg/L) are frequently found in wastewater and that techniques such as reverse osmosis, ozonation, and activated sludge have the best removal efficiency, achieving values of 99%. It was concluded that reverse osmosis is one of the most efficient techniques for eliminating ofloxacin, sulfamethoxazole, carbamazepine, and diclofenac from municipal wastewater, with removal rates ranging from 96 to 99.9%, while for hospital wastewater the activated sludge technique proved to be efficient, eliminating analgesics and antibiotics in the range of 41-99%.
Asunto(s)
Ozono , Contaminantes Químicos del Agua , Aguas Residuales/análisis , Aguas del Alcantarillado , Diclofenaco , Naproxeno/análisis , Norfloxacino , Contaminantes Químicos del Agua/análisis , Carbamazepina/análisis , Hospitales , Ozono/análisis , Sulfametoxazol , Antibacterianos , Ofloxacino , Preparaciones Farmacéuticas , Eliminación de Residuos Líquidos/métodosRESUMEN
Biochar (BP) obtained from palm fiber wastes was combined with H2O2, peroxymonosulfate (PMS), or persulfate (PDS) to treat valsartan, acetaminophen, and cephalexin in water. BP activated PMS and PDS but no H2O2. Computational calculations indicated that interactions of PMS and PDS with BP are more favored than those with HP. The highest synergistic effect was obtained for the removal of valsartan by BP + PMS. This carbocatalytic process was optimized, evaluating the effects of pH, BP dose, and peroxymonosulfate concentration, and minimizing the oxidant quantity to decrease costs and environmental impacts of the process. SO4â¢-, HOâ¢, 1O2, and O2â¢- were the agents involved in the degradation of the pharmaceuticals. The reusability of BP was tested, showing that the carbocatalytic process removed â¼80% of target pollutants after 120 min of treatment even at the fourth reuse cycle. Also, the process decreased the phytotoxicity of the treated sample. Simulated hospital wastewater was treated and its components induced competing effects, but the system achieved the target pharmaceuticals removal in this matrix. Additionally, the analysis of environmental impact using a life cycle assessment unraveled that the carbocatalytic process had a carbon footprint of 2.87 Kg CO2-Eq, with the biochar preparation (which involves the use of ZnCl2 and electric energy consumption) as the main hotspot in the process.
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Oxidantes , Contaminantes Químicos del Agua , Acetaminofén , Dióxido de Carbono/análisis , Cefalexina/análisis , Carbón Orgánico , Peróxidos , Preparaciones Farmacéuticas , Valsartán/análisis , Aguas Residuales/análisis , Agua/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Wastewater treatment using constructed wetlands (CWs) based on natural wetlands constitute a viable alternative with excellent cost and benefit, presenting themselves as efficient technologies in the secondary and tertiary treatment of wastewaters with low implementation, operation, and maintenance costs. The present study aims to evaluate the use of bamboo species, as an alternative to macrophytes, frequently used in CWs, through bibliometric analysis, besides to a review based on case studies. The maps generated by the VOSviewer software and by the analyses of the Web of Science and Scopus databases allowed for a review of typical concepts of CWs, in addition to revealing potential benefits of using bamboos in CWs, such as their hyperaccumulation capacity and bioproduct generation. Other promising aspects were identified, for example the use of bamboo charcoal as a substrate used in subsurface wetlands and the application of ornamental bamboo species for landscape improvements, among other observations. The efficiencies found in six case studies showed values between 89-99.7%, 47.6-99.7%, 58.3-99.9%, and 85.5-99.8% for BOD5, COD, total nitrogen (TN), and total phosphorus (TP), respectively. Despite the promising results, the lack of studies using bamboos in CWs for the treatment of wastewaters limits an assertive statement about the use of this technology, requiring further research, focusing on the morphological functions of bamboos in this treatment with landscape integration and resources recovery.
Asunto(s)
Purificación del Agua , Humedales , Carbón Orgánico , Nitrógeno , Fósforo , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Purificación del Agua/métodosRESUMEN
The analysis of chemical oxygen demand (COD) plays an important role in measuring water pollution, but it normally has a high ecological price. Advances in image acquisition and processing techniques enable the use of mobile devices for analytical purposes. Here, the PhotoMetrix PRO application was used for image acquisition and multivariate analysis. Statistical analysis showed no significant difference in the results compared to the standard method, with no adverse effect of the volume reduction. The cost of analysis and waste generation were reduced by one third, while the analysis time was reduced by one fifth. The miniaturized method was successfully employed in the analysis of several matrices and for the evaluation of advanced oxidation processes. The AGREE score was improved by 25% due to miniaturization. For these reasons, the miniaturized PhotoMetrix PRO method is a suitable option for COD analysis, being less hazardous to the environment due to reductions in the chemicals used and in waste generation.
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Peróxido de Hidrógeno , Contaminantes Químicos del Agua , Análisis de la Demanda Biológica de Oxígeno , Peróxido de Hidrógeno/análisis , Hierro/análisis , Oxidación-Reducción , Oxígeno/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
This study evaluated the effectiveness of a biocoagulant produced from the devilfish invasive species and its combination with two chemical coagulants (aluminum sulfate and ferric sulfate) to remove turbidity, chemical oxygen demand, and total suspended solids in ceramic industry wastewater using a combined experimental design of Mixture-Process. This design optimized the coagulation process and evaluated the effects and interactions between mixture components and coagulant doses. An analysis of variance was used to analyze the experimental data obtained in the study, and the response surface plots by response type (turbidity, chemical oxygen demand, and total suspended solids) were obtained. Results showed that the coagulation treatment could be technically and economically feasible since efficiencies of turbidity, chemical oxygen demand, and total suspended solids removal of 74, 79, and 94% could be achieved using an optimal coagulant dose of 800 mg/L with a mixture of 35% biocoagulant and 65% ferric sulfate. Analysis of variance results showed that the models are significant, and the lack of fit is not required according to the probability value (p value), which were < 0.0001, and > 0.05, respectively. Hence, the experimental data were fitted to a combined reduced special cubic x linear model. These results support the use of devilfish meal as a biocoagulant, being more feasible in dual systems when mixed with ferric sulfate.
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Contaminantes Químicos del Agua , Purificación del Agua , Cerámica , Floculación , Especies Introducidas , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodosRESUMEN
Wastewater treatment plants (WWTPs) have been widely investigated in Europe, Asia and North America regarding the occurrence and fate of antibiotic resistance (AR) elements, such as antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and antibiotic resistant bacteria and pathogens. However, monitoring data about AR elements in municipal WWTPs in Brazil are scarce. This study investigated the abundance of intI1, five ARGs (sul1, tetA, blaTEM, ermB and qnrB) and 16S rRNA in raw and treated wastewater of three WWTPs, using different sewage treatments named CAS (Conventional activated sludge), UASB/BTF (UASB followed by biological trickling filter) and MAS/UV (modified activated sludge with UV disinfection stage). Bacterial diversity and the presence of potentially pathogenic groups were also evaluated, and associations between genetic markers and the bacterial populations were presented. All WWTPs decreased the loads of genetic markers finally discharged to receiving water bodies and showed no evidence of being hotspots for antimicrobial resistance amplification in wastewater, since the abundances of intI1 and ARGs within the bacterial population were not increased in the treated effluents. UASB/BTF showed a similar performance to that of the CAS and MAS/UV, reinforcing the sanitary and environmental advantages of this biological treatment, widely applied for wastewater treatment in warm climate regions. Bacterial diversity and richness increased after treatments, and bacterial communities in wastewater samples differed due to catchment areas and treatment typologies. Potential pathogenic population underwent considerable decrease after the treatments; however, strong significant correlations with intI1 and ARGs revealed potential multidrug-resistant pathogenic bacteria (Aeromonas, Arcobacter, Enterobacter, Escherichia-Shigella, Stenotrophomonas and Streptococcus) in the treated effluents, although in reduced relative abundances. These are contributive results for understanding the fate of ARGs, MGEs and potential pathogenic bacteria after wastewater treatments, which might support actions to mitigate their release into Brazilian aquatic environments in the near future.
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Microbiota , Purificación del Agua , Antibacterianos/farmacología , Bacterias/genética , Brasil , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Marcadores Genéticos , Secuencias Repetitivas Esparcidas , ARN Ribosómico 16S/genética , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisisRESUMEN
Dynamic single-drop microextraction (SDME) was automatized employing an Arduino-based lab-made Cartesian robot and implemented to determine parabens in wastewater samples in combination with liquid chromatography-tandem mass spectrometry. A dedicated Arduino sketch controls the auto-performance of all the stages of the SDME process, including syringe filling, drop exposition, solvent recycling, and extract collection. Univariate and multivariate experiments investigated the main variables affecting the SDME performance, including robot-dependent and additional operational parameters. Under selected conditions, limit of detections were established at 0.3 µg/L for all the analytes, and the method provided linear responses in the range between 0.6 and 10 µg/L, with adequate reproducibility, measured as intraday relative standard deviations (RSDs) between 5.54% and 17.94%, (n = 6), and inter-days RSDs between 8.97% and 16.49% (n = 9). The robot-assisted technique eased the control of dynamic SDME, making the process more feasible, robust, and reliable so that the developed setup demonstrated to be a competitive strategy for the automated extraction of organic pollutants from water samples.
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Microextracción en Fase Líquida , Robótica , Contaminantes Químicos del Agua , Cromatografía Liquida , Microextracción en Fase Líquida/métodos , Parabenos/análisis , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The abuse of legal and illegal drugs is a global public health problem, also affecting the social and economic well-being of the population. Thus, there is a significant interest in monitoring drug consumption. Relevant epidemiological information on lifestyle habits can be obtained from the chemical analysis of urban wastewater. In this work, passive sampling using polar organic chemical integrative samplers (POCIS) was used to quantify licit and illicit drugs biomarkers in wastewater for the application of wastewater-based epidemiology (WBE). In this WBE study, a small urban community of approximately 1179 inhabitants was monitored from 18 March 2020 to 3 March 2021, covering the mobility restriction and flexibilization periods of the COVID-19 pandemic in Brazil. Consumption was estimated for amphetamine, caffeine, cocaine, MDMA, methamphetamine, nicotine, and THC. The highest estimated consumption among illicit drugs was for THC (2369 ± 1037 mg day-1 1000 inh-1) followed by cocaine (353 ± 192 mg day-1 1000 inh-1). There was a negative correlation between consumption of caffeine, cocaine, MDMA, nicotine, and THC with human mobility, expressed by cellular phone mobility reports (P-value = 0.0094, 0.0019, 0.0080, 0.0009, and 0.0133, respectively). Our study is the first long-term drug consumption evaluation during the COVID-19 pandemic, with continuous sampling for almost a whole year. The observed reduction in consumption of both licit and illicit drugs is probably associated with stay-at-home orders and reduced access, which can be due to the closure of commercial facilities during some time of the evaluated period, smaller drug supply, and reduced income of the population due to the shutdown of companies and unemployment. The assay described in this study can be used as a complementary and cost-effective tool to the long-term monitoring of drug use biomarkers in wastewater, a relevant epidemiological strategy currently limited to short collection times.
Asunto(s)
COVID-19 , Cocaína , Drogas Ilícitas , N-Metil-3,4-metilenodioxianfetamina , Trastornos Relacionados con Sustancias , Contaminantes Químicos del Agua , Anfetamina , Brasil/epidemiología , COVID-19/epidemiología , Cafeína/análisis , Cocaína/análisis , Dronabinol , Humanos , Drogas Ilícitas/análisis , N-Metil-3,4-metilenodioxianfetamina/análisis , Nicotina/análisis , Pandemias , Detección de Abuso de Sustancias , Trastornos Relacionados con Sustancias/epidemiología , Aguas Residuales/análisis , Monitoreo Epidemiológico Basado en Aguas Residuales , Contaminantes Químicos del Agua/análisisRESUMEN
Implementation of resource recovery technologies is becoming increasingly important, as humans are exhausting the world's natural resources. Recovering nutrients and water from wastewater treatment systems will play an important role in changing the current trends towards a circular economy. However, guidance is still needed to determine the most appropriate way to do this. In this study two decision-support tools, sanitation planning software (Santiago) and life cycle assessment (LCA), were applied to identify appropriate technologies and their environmental impacts. As a case study, current and alternative scenarios for a wastewater treatment plant (WWTP) in Campo Grande, west-central Brazil, were used. Among 12 scenarios provided by Santiago for efficient nutrient recovery, eight were selected for further assessment. The current WWTP system (UASB reactors) resulted in the highest negative impacts in two of nine assessment categories (freshwater and marine eutrophication), due to nutrient discharge to water. A source separation scenario with urine stored in a urine bank and co-composting of feces showed best overall performance. Electricity consumption played a crucial role for impacts in several categories, while water consumption was not significantly affected by choice of toilet. One Santiago scenario matched the most appropriate scenario with the best environmental performance, but the other seven scenarios were not as beneficial, indicating a need for some adjustments in the software. These results highlight the importance of performing LCA to compare alternative scenarios, even when using a tool designed to identify locally appropriate technologies. The results also indicate that the current wastewater treatment system has reasonable environmental performance, but could be improved if measures were taken to recover energy and reuse water.
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Eliminación de Residuos Líquidos , Aguas Residuales , Animales , Brasil , Humanos , Estadios del Ciclo de Vida , Saneamiento , Programas Informáticos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , AguaRESUMEN
Surfactants are substances that when in aquatic environments can cause negative impacts. Hospital effluents carry numerous chemicals daily, including surfactants, used in sanitization and disinfection procedures. These chemicals are found in the effluents and reach water bodies due to a lack of proper removal in the wastewater treatment plants. The present study investigated data about wastewater monitored from healthcare facilities located in the city of Belo Horizonte, Brazil, focusing on anionic surfactants. The results showed 72 establishments monitoring this parameter, resulting in a median concentration of 1 mg L-1 and 2.49 mg L-1 mean value of anionic surfactants, between 2007 and 2019. It is also observed in the correlation between surfactants and oils in all healthcare establishment sizes, except for the medium-sized. Although anionic surfactants are the most used in cleaning product formulations, cationic surfactants still do not have specific legislation in the studied country that dictates a limit for discharge into sewage; consequently, they are not routinely monitored in effluents. However, these compounds are used in the formulation of routine hospital products.
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Monitoreo del Ambiente , Contaminantes Químicos del Agua , Brasil , Atención a la Salud , Tensoactivos/química , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Polychlorinated biphenyls (PCBs) are persistent and bioaccumulable organic compounds. The occurrence of PCBs was assessed in two populations of the intertidal sea anemone Bunodosoma zamponii living under different anthropogenic strains. One location was in vicinity to a wastewater plant (Las Delicias, LD), and the other was a preserved location chosen as a reference site (Punta Cantera, PC). Anemone populations were sampled 4 times (spring, summer, autumn and winter) throughout a year, in addition to seawater and sediment from those areas. PCB loadings ranged from 2.89 to 79.41 ng L-1 in seawater samples and from 0.07 to 6.61 ng g-1 dry weight in sediment samples. Total PCB levels ranged from 0.22 to 14.94 and 2.79 to 24.69 ng g-1 wet weight in anemones from PC and LD, respectively. PCBs concentrations in anemones from LD were significantly greater than PC during spring, summer and winter. The congeners 18 and 44 prevailed in seawater samples, 44 and 52 in sediment and 18 and 132+153 in anemones. Redundancy analysis integrated PCB levels from all matrixes and bolstered contrast between sampling sites. Seasonality was also a relevant factor since during winter PCB loading was greater in sediment and anemone samples, coincident with the rainiest season. Disparity between sites could be due to LD's proximity to the wastewater plant, effect of littoral drift direction and/or asymmetries in anemones physiological condition.
Asunto(s)
Bifenilos Policlorados , Anémonas de Mar , Contaminantes Químicos del Agua , Animales , Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Bifenilos Policlorados/análisis , Agua de Mar , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The use of treated wastewater (TWW) for irrigation has gained global attention since it reduces pressure on groundwater (GW) and surface water. This study aimed to evaluate the effect of TWW on agronomic, photosynthetic, stomatal, and nutritional characteristics of barley plants. The experiment with barley was established on two bands: one band was irrigated with GW and the other with TWW. The evaluation was performed 25, 40, 60, 90, and 115 days after sowing (DAS). Results showed that irrigation with TWW increased (p < 0.01) grain yield by 54.3% and forage yield by 39.4% compared to GW irrigation. In addition, it increased plant height (PH) (p = 0.013), chlorophyll concentration index (CCI) (p = 0.006), and leaf area index (LAI) (p = 0.002). TWW also produced a positive effect (p < 0.05) in all the photosynthetic efficiency parameters evaluated. Barley plants irrigated with TWW had lower stomatal density (SD) and area (SA) (p < 0.001) than plants irrigated with GW. Plants irrigated with TWW had a higher P concentration (p < 0.05) in stems and roots and K concentration in leaves than plants irrigated with GW. We concluded that the use of TWW induced important biochemical, physiological, and agronomic changes in barley plants. Hence, the use of TWW may be a sustainable alternative for barley production in arid and semi-arid regions. This study was part of a government project, which aimed to develop a new metropolitan irrigation district with TWW. This study may contribute to the sustainability of water resources and agricultural practices in northern Mexico.
Asunto(s)
Agua Subterránea , Hordeum , Riego Agrícola , Agricultura/métodos , Clima Desértico , Aguas Residuales/análisisRESUMEN
Techniques using membranes for the treatment of wastewaters usually promote higher quality of treated water when compared to other processes. Among them, pervaporation has advantages in terms of selectivity in addition to low working pressure, which can prevent clogging problems. Polysulfone and polyurethane have complementary characteristics and are interesting in the context of membranes for industrial applications. In this sense, the aim of this work was to prepare and characterize polysulfone/polyurethane-based membranes and tested them with a simulated wastewater containing the reactive black dye and sodium chloride by pervaporation. In their manufacture, thermal treatment (at 60°C) and photo-radiation treatment (using ultraviolet light) were also applied. The characterizations were performed using different analytical tools. In general, it was possible to verify that all membranes have a dense layer. The thermal analysis allowed to define that the indicated working temperature is below 50°C. With respect to the simulated wastewater treatment, all membranes reached 100% selectivity. Concerning the saline solution, the mean selectivity was around 98.5%. Moreover, the permeate flow values were within the range presented by commercial membranes ranging from 1.6 to 2.4â kg m-2 h-1. Although for the photoirradiated membranes the photo-graft reaction has occurred, among all membranes, the blend without any treatment stood out from the others, presenting the highest permeate flow of the simulated wastewater. Finally, the results reveal that these membranes are capable of recovering wastewater from textile processes, in addition to having the potential to remove salts from water through the pervaporation process.Highlights Polysulfone/polyurethane-based membranes were not yet evaluated for wastewater recovery.Modifications in the membrane characteristics promoted variations in the permeate flow.Changes in physical-chemical properties of membrane as a result of a photoinitiation reaction.Removal efficiency achieved was 100% for reactive black dye and 98.5% for sodium chloride.A new way of performing pervaporation on the recovery of aqueous solutions.
Asunto(s)
Poliuretanos , Aguas Residuales , Membranas Artificiales , Polímeros , Cloruro de Sodio , Sulfonas , Textiles , Aguas Residuales/análisis , AguaRESUMEN
Wastewater release in an urban wetland in Mexico City entails discharging complex mixtures of hundreds of chemical substances into the aquatic system. Therefore, in order to identify the most important contaminants, a GC-MS screening method coupled with deconvolution software was used. LC50 values from ECOSAR and Toxic Units were obtained to identify the organic pollutants-of-concern and to pinpoint the most ecotoxic sites. The results showed that, even though the area has intensive farming, agrochemicals are not of concern. Industrial and domestic groups make up from about 30%-66% of the pollutants for all sites. Of the 189 identified substances, 17 were detected 44% of the time and the Toxic Unit showed that terbutol, coprostanol, and hexadecane were capable of generating considerable adverse effects on the aquatic ecosystem. Total Toxic Units for each site exhibited a decreasing trend as they distanced from the urban and agricultural area.
Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , HumedalesRESUMEN
The main objective of the current study was to assess the impact of the water taken from the 'Tunisian Refining Industries Company' on meiobenthic nematodes, before and after a series of treatments in decantation basins followed by its discharge in Bizerte bay, Tunisia. The comparison of environmental parameters of the two types of water was clearly indicative of an improvement in the quality of treated waters after a significant reduction in their loads in hydrocarbons. Overall, the water retained a good quality after being treated by 'Tunisian Refining Industries Company' before discharge in the sea. At the end of the experiment, differential responses were observed according to the richness of sediment in organic matter and hydrocarbons. Thus, it was apparent that the nematode assemblage exposed to the treated waters was closer to controls and associated to higher values of abundance, than that under untreated ones. It was also assumed that the species Microlaimus honestus De Man, 1922, Paramonohystera proteus Wieser, 1956 and Cyartonema germanicum Juario, 1972 are sensitive bioindicators of bad environmental statues and of hydrocarbon presence in the environment. On the other hand, Metoncholaimus pristiurus (Zur Strassen, 1894) Filipjev, 1918 would rather be classified as a positive bioindicative species of this type of pollutants.(AU)
O principal objetivo do presente estudo foi avaliar o impacto da água retirada da "Tunisian Refining Industries Company" sobre os nematoides meiobentônicos, antes e depois de uma série de tratamentos em bacias de decantação seguidos de seu descarte na baía de Bizerte, Tunísia. A comparação dos parâmetros ambientais dos dois tipos de água foi claramente indicativa de uma melhoria na qualidade das águas tratadas após uma redução significativa das suas cargas em hidrocarbonetos. No geral, a água reteve uma boa qualidade após ser tratada pela "Tunisian Refining Industries Company" antes da descarga no mar. Ao final do experimento, foram observadas respostas diferenciais de acordo com a riqueza de sedimentos em matéria orgânica e hidrocarbonetos. Assim, ficou claro que a assembleia de nematoides exposta às águas tratadas estava mais próxima dos controles e associada a maiores valores de abundância do que nas não tratadas. Também foi assumido que as espécies Microlaimus honestus De Man, 1922, Paramonohystera proteus Wieser, 1956 e Cyartonema germanicum Juario, 1972 são bioindicadores sensíveis de más estátuas ambientais e da presença de hidrocarbonetos no meio ambiente. Por outro lado, Metoncholaimus pristiurus (Zur Strassen, 1894) Filipjev, 1918 preferiria ser classificado como uma espécie bioindicativa positiva deste tipo de poluentes.(AU)