RESUMEN
This study reports enhanced organic dye adsorption capacity from aqueous solutions of a synthesized novel biocomposite hydrogel based on aminated lignin (AL) and poly(3-acryloamidopropyl)-trimethylammonium chloride P(ClAPTA). The biocomposites were characterized via Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and elemental analysis, confirming successful functionalization and polymerization. A factorial design was used to screen the operational parameters, showing that the P(ClAPTA-AL) composition was the most significant factor affecting dye adsorption compared to the amination ratio. Optimization of the adsorption process was achieved using alizarin red S (ARS) as a model dye through a Box-Behnken design, revealing optimal conditions: pH 12.0, 20 °C, 120 min contact time, and a composite-to-ARS mass ratio of 10, resulting in a high adsorption capacity of 102.1 mg g-1 and a maximum adsorption of 3889 mg g-1. Kinetic studies showed an adsorption process followed a pseudo-second-order model, confirming chemisorption as the predominant mechanism, while thermodynamic analysis revealed a spontaneous and endothermic adsorption process. Furthermore, promissory results demonstrated high reusability, with adsorption efficiency remaining at â¼99 % until the fourth cycle and maintaining 81.1 % after seven cycles.
Asunto(s)
Colorantes , Hidrogeles , Lignina , Aguas Residuales , Contaminantes Químicos del Agua , Lignina/química , Adsorción , Aguas Residuales/química , Hidrogeles/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Cinética , Colorantes/química , Purificación del Agua/métodos , Concentración de Iones de Hidrógeno , Termodinámica , Aminación , Antraquinonas/química , Espectroscopía Infrarroja por Transformada de Fourier , TemperaturaRESUMEN
This study aimed to investigate the dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in water samples obtained during the coronavirus disease 2019 pandemic period, employing cross-assembly phage (crAssphage) as a fecal contamination biomarker and next-generation sequencing protocols to characterize SARS-CoV-2 variants. Raw wastewater and surface water (stream and sea) samples were collected for over a month in Rio de Janeiro, Brazil. Ultracentrifugation and negatively charged membrane filtration were employed for viral concentration of the wastewater and surface water samples, respectively. Viruses were detected and quantified by (RT-)qPCR applying TaqMan® system protocols. SARS-CoV-2 RNA signals were detected in 92.5% (37/40) of the wastewater samples and in 31.25% (10/32) of the stream water samples, but not in seawater samples. CrAssphage was detected in 100% of the wastewater samples, 93.75% (30/32) of the stream samples, and in 2/4 of the seawater samples. CrAssphage detection and high concentrations in stream surface waters (median 8.95 log10 gc/L) revealed diffuse contamination by domestic wastewater in a region with high sanitary coverage. The correlations detected between SARS-CoV-2 data and the moving averages of clinical cases per capita over the sampling period were moderate to strong when applying a 13-day offset, regardless of normalization by crAssphage data or not. Sequencing of the receptor-binding domain of the spike protein confirmed the detection of SARS-CoV-2, but did not characterize the circulating variant. On the other hand, the whole genome sequencing protocol identified circulation of the Gamma variant, corroborating the sampling period clinical data.
Asunto(s)
COVID-19 , Secuenciación de Nucleótidos de Alto Rendimiento , SARS-CoV-2 , Aguas Residuales , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/clasificación , Aguas Residuales/virología , Humanos , COVID-19/virología , COVID-19/transmisión , Brasil , Bacteriófagos/genética , Bacteriófagos/aislamiento & purificación , Bacteriófagos/clasificación , ARN Viral/genética , ARN Viral/aislamiento & purificación , Agua de Mar/virología , Genoma ViralRESUMEN
The reliance on agriculture in many nations has increased the use of treated wastewater for irrigation. However, reclaimed water still poses health risks from resistant pathogens like Cryptosporidium spp. Ozone, a strong disinfectant, has been used in water treatment. This study assessed the microbiological quality of treated wastewater for irrigation and evaluated ozone effectiveness in inactivating C. parvum oocysts. All samples contained Cryptosporidium spp., with 163 to 850 oocysts 100 L-1, and 50% contained viable oocysts. When C. parvum was exposed to different ozone residual concentrations (0.1, 0.8, and 1.3 mg L-1), oocyst viability reduction of 73%, 85%, and 99% and infectivity of 0.8, 1.36, and 2 Log10 was achieved. The predicted values for infectious oocysts were 4.19, 3.64, and 3.27, representing absolute counts of infective oocysts after ozone treatment. These findings demonstrate ozone's effectiveness in inactivating C. parvum in treated wastewater, supporting its potential for safe water reuse. PRACTITIONER POINTS: All wastewater samples contained Cryptosporidium spp., with 163 to 850 oocysts per 100 L. Wastewater had 50% contained viable oocysts. Ozone concentrations (0.1, 0.8, 1.3 mg/l) achieved oocyst viability of 73.33%, 85.0%, and 99.4%, respectively. The predicted values for infectious oocysts were 4.19, 3.64, and 3.27, respectively for each ozone concentration.
Asunto(s)
Riego Agrícola , Cryptosporidium parvum , Desinfección , Ozono , Aguas Residuales , Purificación del Agua , Ozono/farmacología , Cryptosporidium parvum/efectos de los fármacos , Aguas Residuales/parasitología , Aguas Residuales/química , Desinfección/métodos , Purificación del Agua/métodos , Oocistos/efectos de los fármacos , Eliminación de Residuos Líquidos/métodosRESUMEN
This study assesses the occurrence of emerging contaminants (ECs) from agricultural and livestock production activities along the Salado River (Santa Fe province, Argentina). Of the 23 ECs studied, 8 were detected and quantified in river and wastewater samples, including ciprofloxacin, enrofloxacin, chlorpyrifos-methyl, albendazole, fenbendazole, levamisole, diazepam, and thiamethoxam. In river samples, the highest concentrations corresponded to ciprofloxacin, chlorpyrifos-methyl, and enrofloxacin. In wastewater samples, albendazole, fenbendazole, ciprofloxacin, enrofloxacin, and thiamethoxam were found. The detection frequency ranged from 4.2% to 54.2% in river samples and from 11.1% to 22.2% in wastewater samples. The spatial distribution of contaminants showed different concentrations, with higher levels often found near urban and agricultural areas, suggesting anthropogenic sources. Ecological risk assessments for different organisms were conducted. Ciprofloxacin posed the highest risk, especially affecting bacteria, cyanobacteria, and algae. Diazepam also was found to pose significant risks to algae, crustaceans, and fishes. Chlorpyrifos-methyl was identified as highly hazardous to multiple living organisms, which is in agreement with the fish mortality that occurred at the sampling sites. The risk assessment in humans showed differences among children, adolescents, and adults, with infants (6 months to 1 year) being at a higher risk than adults. Children may be at a higher daily intake of contaminants than adults, raising concerns about the long-term effects of exposure. This work underscores the critical need for monitoring and regulating ECs in aquatic environments. Further studies are necessary to fully understand their impact and to develop effective strategies for mitigating their presence in water systems.
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Monitoreo del Ambiente , Ríos , Aguas Residuales , Contaminantes Químicos del Agua , Ríos/química , Contaminantes Químicos del Agua/análisis , Aguas Residuales/química , Medición de Riesgo , Humanos , Argentina , Niño , Adolescente , Adulto , Animales , Lactante , Preescolar , Adulto JovenRESUMEN
Wastewater treatment plants (WWTPs) currently face major challenges toward the removal of microcontaminants and/or microbial matrices and consequently play an important role in the potential dissemination of biological resistance in freshwater. The ultraviolet (UV) system is a tertiary treatment strategy increasingly applied worldwide, although many studies have shown that disinfected effluent can still contain antibiotic-resistant bacteria and resistance genes. Therefore, to better understand the effects of UV radiation doses on the removal of all resistance elements (antibiotics, antibiotic-resistant bacteria, and antibiotic resistance genes), the present study was designed using a pilot-scale photoreactor. The UV doses could be varied to investigate whether there is an optimal UV dose capable of removing all resistance elements and also if the UV dose frequently applied in full-scale systems is able to reduce the resistance elements. The effect of different UV doses (A, 0-10 mJ/cm2; B, 10-15 mJ/cm2; and C, > 15 mJ/cm2) in a pilot-scale photoreactor on the removal of antibiotics, antibiotic-resistant bacteria, and genes from the effluent of a UASB reactor followed by a biological trickling filter system (UASB-TF) fed with real sanitary sewage was investigated. Samples of influent and effluent from the UVC photoreactor were collected, and the concentration levels of norfloxacin (NOR), ciprofloxacin (CIP), and levofloxacin (LEV) were assessed. The qnrB, sul1, ermB, integron-integrase (intI1), and 16S rRNA genes, total heterotrophic bacteria (THB), and bacterial resistance to azithromycin and sulfamethoxazole were also investigated. Results indicated that LEV and intI1 were found in the highest median concentrations in the photoreactor influent. Although most antibiotics (NOR and CIP) and ARGs (intI1, 16S rRNA, and qnrB) were apparently better removed with the highest UV dose (> 15 mJ/cm2) applied, except for LEV, sul1, and ermB genes, the Kruskal-Wallis test reported no significant difference between low and high doses. ARB removal (from 80 to 100%) was observed at all UV doses. Principal component analysis (PCA) suggested a clear pattern of pollutant groups, i.e., antibiotics, ARG, and ARB, which exhibited low (median of 8-16%), medium (37-96%), and high (> 97%) removal percentages, respectively. These results demonstrated that UVC photoreactors can be an alternative to complement biological treatment in sewage treatment plants at the dose normally applied in full-scale WWTPs (> 15 mJ/cm2). However, there was no optimal single dose capable of removing all the resistance elements investigated.
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Farmacorresistencia Microbiana , Aguas del Alcantarillado , Aguas Residuales , Purificación del Agua , Purificación del Agua/métodos , Aguas del Alcantarillado/microbiología , Farmacorresistencia Microbiana/genética , Contaminación del Agua/estadística & datos numéricos , Aguas Residuales/microbiología , Aguas Residuales/estadística & datos numéricos , Antibacterianos , Microbiología del Agua , Genes Bacterianos , Dosis de RadiaciónRESUMEN
High salts concentrations in wastewater hinder its biological treatment. Recent research has investigated the inhibitory effect of salinity on the anammox process, mainly focusing on NaCl. Thus, the inhibition caused by multi-electrolytes salinity on freshwater anammox bacteria remains unclear. In this study, the anammox process was evaluated for the treatment of multi-electrolyte saline wastewater (NaCl, MgCl2, and CaCl2) during 684 days in three operational phases. In Phase 1, the anammox inoculum was successfully adapted from sidestream (232 mgN.L-1) to mainstream (60 mgN.L-1) conditions, with no damage to the reactor performance, at an hydraulic retention time of 1.4 h. In Phase 2, salinity was gradually increased in the synthetic medium to adapt the freshwater anammox bacteria. The anammox bacteria tolerated a total salinity of 0.72 wt% (in g.L-1: 4.7 NaCl, 2.0 MgCl2, and 0.6 CaCl2), achieving an 84.3 ± 0.8% nitrogen removal efficiency. The presence of salts favored the Ca. Jettenia genus over Ca. Brocadia after long-term exposure to salinity. Finally, in Phase 3, anaerobically pre-treated saline wastewater (0.72 wt%) was applied to the anammox reactor. The presence of residual organic matter (53 mgCOD.L-1; COD/N of 0.86) resulted in partial deviation of the metabolic pathway from anammox to, especially, nitrite heterotrophic denitrification, resulting in the accumulation of ammonia-N in the effluent. Even so, the anammox process was predominant, being responsible for 83% of the nitrogen removal. The presence of both organic matter and salinity led to a shift in dominance from the Ca. Jettenia genus to Ca. Brocadia.
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Nitrógeno , Salinidad , Aguas Residuales , Aguas Residuales/química , Nitrógeno/metabolismo , Reactores Biológicos , Electrólitos/metabolismo , Eliminación de Residuos Líquidos/métodosRESUMEN
Proper waste management and sustainable energy production are crucial for human development. For this purpose, this study evaluates the impact of blending percentage on energy recovery potential and environmental benefits of co-combustion of wastewater sludge and Brazilian low-rank coal. The sludge and coal were characterised in terms of their potential as fuel and co-combustion tests were carried out in a pilot-scale bubbling fluidised bed focused on the influence of the percentage of sludge mixture on the behaviour of co-combustion with coal in terms of flue gas composition and fluidised bed temperature stability. Sludge has a higher heating value (16.276 MJ/kg) than coal (15.486 MJ/kg) and a higher fuel ratio (8.48 vs. 0.21). The O2 and CO2 levels found in the co-combustion tests, together with a very low CO concentration, indicate good combustion. However, the NOx emission was considerable, varying from 825.2 ± 94.5 to 1,320.5 ± 33.8 mg/m3 (O2ref = 7 %), pointing to the need for actions to reduce atmospheric pollution. Coal had higher ash content (52.64 % vs. 25.00 % d.b.). The temperatures in the bed region and in the combustion region showed similar behaviour for all the fuels. The addition of sewage sludge to mineral coal reduced the ash content without increasing the ash fusibility risk in the combustion temperature range evaluated. These findings suggest that sludge addition in co-combustion with coal offers promising results for both energy production and environmental sustainability.
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Carbón Mineral , Aguas del Alcantarillado , Aguas Residuales , Brasil , Aguas del Alcantarillado/química , Aguas Residuales/química , Incineración/métodos , Eliminación de Residuos Líquidos/métodosRESUMEN
The deammonification process is an efficient alternative to remove nitrogen from wastewater with a low carbon/nitrogen ratio. However, the reactor configuration and operational factors pose challenges for applications in treatment systems to remove nitrogen from municipal and industrial wastewater on a large scale. To address this gap, this study evaluated a new deammonification strategy using a single-stage membrane aerated biofilm reactor (MABR), operated with continuous flow, under different hydraulic retention times (HRT) in the post-treatment of poultry slaughterhouse wastewater with a low nitrogen load, similar to domestic wastewater. The performance of the MABR reactor and the microbial community was evaluated over a long period at HRTs of 12, 24, and 36 hours, corresponding to nitrogen volumetric loads of 181.0 g N.m-3.d-1, 87.4 g N.m-3.d-1 and 67.8 g N.m-3.d-1. The results show that total nitrogen (TN) removal and the microbial community in the MABR reactor were influenced by changes in HRT. The highest efficiency in TN removal was obtained with an HRT of 24 hours, in which the maximum TN removal efficiency was 77.04%. Candidatus Brocadia and Candidatus Jettenia were the two genera of bacteria with Anammox activity present in the reactor, with relative abundances of 7.27% and 0.74%, respectively. This study helps to deepen the understanding of the application of the single-stage MABR reactor in real wastewater treatment with a low nitrogen load.
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Mataderos , Biopelículas , Reactores Biológicos , Nitrógeno , Aves de Corral , Eliminación de Residuos Líquidos , Aguas Residuales , Reactores Biológicos/microbiología , Animales , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Microbiota , Bacterias/metabolismoRESUMEN
Human respiratory and enteric viruses are responsible for substantial morbidity and mortality worldwide. Wastewater-based epidemiology utilizing next-generation sequencing serves as an effective tool for monitoring viral circulation dynamics at the community level. However, these complex environmental samples are often laden with other microorganisms and host genomic material, which can hinder the sensitivity of viral detection. To address this limitation, targeted enrichment sequencing is emerging as a preferred strategy, facilitating the acquisition of a more comprehensive understanding of specific pathogens. In this study, we evaluated the performance of a targeted enrichment sequencing panel for 42 excreted respiratory viruses (including Picornaviridae, Adenoviridae, Coronaviridae, Paramyxoviridae, Orthomyxoviridae, Orthoherpesviridae, Pneumoviridae, and Parvoviridae families), known as the Respiratory Pathogen ID/AMR enrichment panel (RPIP), coupled with Explify bioinformatics analysis in 3 sewage samples from Uruguay. RPIP panel successfully identified sequences from frequently circulating viruses, along with some that had not been documented previously. We identified and characterized various viruses, including human Enterovirus (Coxsackievirus A1 and A19), Influenza A-H1N1, and full-length sequences of SARS-CoV-2. Additionally, several other viral pathogens were detected, such as human Bocavirus, human Parechovirus, Enterovirus A71, and Enterovirus D68; however, for these viruses further analysis was limited due to the small genomic regions or low-read coverage obtained. While the RPIP panel necessitates substantial sequencing depth and may introduce bias towards the more predominant strains present in the samples, this approach suggests its viability as a genomic epidemiological tool for assessing respiratory and enteric viruses in wastewater.
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Secuenciación de Nucleótidos de Alto Rendimiento , Virus , Aguas Residuales , Humanos , Aguas Residuales/virología , Virus/aislamiento & purificación , Virus/genética , Virus/clasificación , Uruguay/epidemiología , Aguas del Alcantarillado/virología , Infecciones del Sistema Respiratorio/virología , Infecciones del Sistema Respiratorio/epidemiología , Genoma Viral , Genómica/métodos , Virosis/virología , Virosis/epidemiologíaRESUMEN
Detection and quantification of disease-related biomarkers in wastewater samples, denominated Wastewater-based Surveillance (WBS), has proven a valuable strategy for studying the prevalence of infectious diseases within populations in a time- and resource-efficient manner, as wastewater samples are representative of all cases within the catchment area, whether they are clinically reported or not. However, analysis and interpretation of WBS datasets for decision-making during public health emergencies, such as the COVID-19 pandemic, remains an area of opportunity. In this article, a database obtained from wastewater sampling at wastewater treatment plants (WWTPs) and university campuses in Monterrey and Mexico City between 2021 and 2022 was used to train simple clustering- and regression-based risk assessment models to allow for informed prevention and control measures in high-affluence facilities, even if working with low-dimensionality datasets and a limited number of observations. When dividing weekly data points based on whether the seven-day average daily new COVID-19 cases were above a certain threshold, the resulting clustering model could differentiate between weeks with surges in clinical reports and periods between them with an 87.9% accuracy rate. Moreover, the clustering model provided satisfactory forecasts one week (80.4% accuracy) and two weeks (81.8%) into the future. However, the prediction of the weekly average of new daily cases was limited (R2 = 0.80, MAPE = 72.6%), likely because of insufficient dimensionality in the database. Overall, while simple, WBS-supported models can provide relevant insights for decision-makers during epidemiological outbreaks, regression algorithms for prediction using low-dimensionality datasets can still be improved.
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Algoritmos , COVID-19 , Aprendizaje Automático , SARS-CoV-2 , Aguas Residuales , COVID-19/epidemiología , COVID-19/diagnóstico , México/epidemiología , Humanos , Aguas Residuales/virología , SARS-CoV-2/aislamiento & purificación , Toma de Decisiones , Medición de Riesgo/métodos , Monitoreo Epidemiológico Basado en Aguas Residuales , Monitoreo Epidemiológico , PandemiasRESUMEN
Antimicrobial resistance (AMR) is a growing global health threat. This study investigated antibiotic resistance in E. coli isolates from municipal wastewater (86 isolates) and clinical urinary tract infection (UTI) cases (34 isolates) in a Grenadian community, using data from January 2022 to October 2023. Antibiogram data, assessed per WHO guidelines for Critically Important antimicrobials (CIA), showed the highest resistance levels in both clinical and wastewater samples for ampicillin, followed by amoxicillin/clavulanic acid and nalidixic acid, all classified as Critically Important. Similar resistance was observed for sulfamethoxazole-trimethoprim (highly important) in both groups, with nitrofurantoin showing resistance in the important category. According to the WHO AWaRe classification, ampicillin (ACCESS group) had the highest resistance, while nitrofurantoin had the lowest across all samples. The WATCH group antibiotics, cefuroxime and cefoxitin, showed comparable resistance levels, whereas aztreonam from the RESERVE group (tested only in wastewater) was 100% sensitive. Multiple Antibiotic Resistance (MAR) index analysis revealed that 7% of wastewater and 38.2% of clinical samples had MAR values over 0.2, indicating prior antibiotic exposure in clinical isolates. These parallel patterns in wastewater and clinical samples highlight wastewater monitoring as a valuable tool for AMR surveillance, supporting antibiotic stewardship through ongoing environmental and clinical assessment.
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Antibacterianos , Escherichia coli , Infecciones Urinarias , Aguas Residuales , Aguas Residuales/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Infecciones Urinarias/microbiología , Antibacterianos/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana , Fenotipo , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/epidemiologíaRESUMEN
Wastewater-based epidemiology (WBE) is a powerful tool to gather epidemiological insights at the community level, providing objective data on population exposure to harmful substances. A considerable portion of the human exposure to these potentially harmful chemicals occurs unintentionally, unlike substances such as pharmaceuticals, illicit drugs, or alcohol. In this context, this comprehensive review analyzes WBE studies focused on classes of organic chemicals to which humans are unintentionally exposed, namely organophosphorus flame retardants, per- and polyfluoroalkyl substances (PFAS), benzotriazoles and benzothiazoles, phthalates and terephthalates, benzophenones, pesticides, bisphenols, and parabens. The review highlights some advantages of WBE for public health surveillance, e.g., non-invasive analysis, predictive capability, nearly real-time data, population-wide insights, no ethical approval, and unbiased sampling. It also discusses challenges and future research directions in WBE regarding exposure to harmful chemicals from various sources. The review emphasizes the critical role of wastewater sampling, sample preparation, quality control, and instrumental analysis in achieving accurate and reliable results. Furthermore, it examines the selection of human biomarkers for WBE studies and explores strategies to link WBE with human biomonitoring (HBM), which together enhance both the precision and effectiveness of exposure assessments.
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Aguas Residuales , Humanos , Aguas Residuales/análisis , Aguas Residuales/química , Exposición a Riesgos Ambientales/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo Epidemiológico Basado en Aguas Residuales , Monitoreo del Ambiente/métodosRESUMEN
Studies have shown the presence of SARS-CoV-2 in the stool of both symptomatic and asymptomatic COVID-19 patients, enabling wastewater-based surveillance (WBS) to complement clinical monitoring. The emergence of variants can enhance viral transmissibility, highlighting the need for ongoing surveillance to detect and control infectious diseases. This study aimed to detect SARS-CoV-2 variants in wastewater from a treatment plant in San Pedro de la Paz, Chile, between January and November 2021. Wastewater samples were concentrated using the polyethylene glycol method, and RT-qPCR assays were performed to analyze SARS-CoV-2 and its variants (Alpha, Beta, Gamma, Lambda, and Delta), with results compared to Illumina amplicon sequencing. The concentration method achieved about 11% viral recovery. The detection of viruses and variants in wastewater proved sensitive and consistent with clinical data, providing additional surveillance insights. Notably, Lambda and Delta variants were the most frequently detected during the second and third infection waves, with some variants identified in wastewater before the first confirmed clinical cases. However, Illumina sequencing lacked sufficient genome coverage, suggesting the need for better sequencing methods for this matrix. This study demonstrates that WBS is a rapid, cost-effective tool for detecting SARS-CoV-2 and its mutations, particularly useful during overwhelming clinical situations or when cost is prohibitively high.
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COVID-19 , SARS-CoV-2 , Aguas Residuales , Aguas Residuales/virología , Chile/epidemiología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , COVID-19/epidemiología , COVID-19/virología , Humanos , Monitoreo Epidemiológico Basado en Aguas ResidualesRESUMEN
In this study, wastewater from a sewage treatment plant was used to culture the microalga, Verrucodesmus verrucosus. The ability of microalgae to adapt to adverse environments and produce high lipid concentrations was evaluated using different media, including sterile and non-sterile media and a control medium. The analysis showed that the control medium (distilled water sample enriched with fertilizer) removed 80.35% ammonium, 32.71% phosphate, and 83.86% nitrate. The sterile raw effluent removed 78.91% of ammonium, 83.44% of phosphate, and 98.82% of nitrate. The optimal conditions for biomass production were sterile raw wastewater, which produced 383.3 mg L-1 of biomass, 2.5% of total lipids, and an average lipid production of 9.31 mg L-1. Microalgae can grow and consume inorganic nutrients under adverse environmental conditions such as in raw wastewater, which is of great importance because it is a pollutant that negatively affects the environment and society. However, wastewater may represent a viable alternative substrate, allowing the generation of high-value products, such as lipids. Furthermore, the specificity of microalgal morphotypes must be evaluated, because each has specific metabolic plasticity. Verrucodesmus verrucosus is a microalga that has not been evaluated in bioremediation processes of wastewater with and without the presence of biotic factors. Therefore, the present study provides a viable alternative for this biological process, with the potential to store metabolites of interest in the industry.
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Microalgas , Aguas Residuales , Aguas Residuales/química , México , Biomasa , Eliminación de Residuos Líquidos/métodosRESUMEN
This work investigates the use of Aspergillus brasiliensis, this particular species of Aspergillus, as a biosorbent for the first time. It is employed to biosorption Zn(II), Cd(II), and Pb(II) and combines the biosorption experiments with electrochemical measurements for in situ analysis. For the experiments, a batch system was employed with the dead biomass. In order to determine the biosorption capacity, the impact of several operational parameters was examined, including pH, temperature, agitation speed, contact time, and initial metal concentration, and the optimum values were 5, 30 °C, 150 rpm, 2 h, and 150 ppm, respectively. Using 0.2 g biomass in 100 mL solution, the maximal uptake of Zn(II), Cd(II), and Pb(II) at ideal conditions was determined to be 33.67, 24.51, and 36.76, respectively. The Langmuir and Freundlich isotherm model was studied for the biosorption process. An electrochemical sensor using nanomaterials is designed and constructed to monitor the concentration of these metals. The silver nanoparticles functionalized with thiosemicarbazide and 6-mercaptohexanoic acid (mercaptohexanoylhydrazinecarbothioamide-coated silver nanoparticles, MHHC-AgNPs) linked to the carboxylated multi-walled carbon nanotubes (MWCNTs) were utilized for glassy carbon electrode modification (MHHC-AgNPs/MWCNTs/GCE). The concentration range of Zn(II) is 0.7-173 µg/L, Cd(II) is 1.18-293 µg/L, and Pb(II) is 2.17-540 µg/L. The detection limits for Zn(II), Cd(II), and Pb(II) are 0.036 µg/L, 0.15 µg/L, and 0.16 µg/L, respectively. Under optimized conditions, these results were obtained using the differential pulse anodic stripping voltammetry method (DPASV). The successful detection of Zn(II), Cd(II), and Pb(II) was achieved by effectively preventing interference from other common ions. It was effectively employed for measuring ions in industrial wastewater, and the results obtained aligned with those acquired from an atomic absorption spectrometer (AAS). Thus, Aspergillus brasiliensis species, along with this electrochemical sensor, can be used to remediate and monitor environmental pollution, Zn(II), Cd(II), and Pb(II), successfully.
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Aspergillus , Cadmio , Plomo , Nanopartículas del Metal , Plata , Aguas Residuales , Zinc , Aguas Residuales/química , Aspergillus/metabolismo , Plata/química , Nanopartículas del Metal/química , Contaminantes Químicos del Agua , AdsorciónRESUMEN
Wastewater serves as a reservoir for antimicrobial-resistant bacteria. This study revealed the presence of carbapenem-resistant and carbapenemase-producing Gram-negative bacilli (GNB), established clonal relationships among isolates in hospital and municipal wastewater, and identified a high-risk clone in municipal wastewater. A total of 63 isolates of GNB were obtained, with Enterobacterales being the most frequently isolated group (62%). Carbapenemase-producing Lelliottia amnigena, Kluyvera cryocrescens, and Shewanella putrefaciens isolates were documented for the first time in Mexico. The detectableted carbapenemase genes were blaKPC (55%), blaNDM (12%), blaVIM-2 (12%), blaOXA-48 (4%), blaGES (2%), blaNDM-1 (2%), and blaNDM-5 (2%). Clonal relationships were observed among Klebsiella pneumoniae and Enterobacter spp. isolates, and remarkably the high-risk clone Escherichia coli ST361, carrying blaNDM-5, was identified. This study demonstrates that wastewater harbours carbapenem-resistant and carbapenemase-producing bacteria, posing a public health threat that requires epidemiological surveillance.
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Proteínas Bacterianas , Bacterias Gramnegativas , Hospitales , Aguas Residuales , beta-Lactamasas , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Aguas Residuales/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , México , Bacterias Gramnegativas/genética , Bacterias Gramnegativas/enzimología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , Enterobacteriaceae/genética , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/enzimología , Enterobacteriaceae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Humanos , Antibacterianos/farmacologíaRESUMEN
Wastewater-based epidemiological surveillance has proven to be a useful and cost-effective tool for detecting COVID-19 outbreaks. Here, our objective was to evaluate its potential as an early warning system in Venezuela by detecting SARS-CoV-2 RNA in wastewater and its correlation with reported cases of COVID-19. Viral RNA was concentrated from wastewater collected at various sites in Caracas (northern Venezuela), from September 2021 to July 2023, using the polyethylene glycol (PEG) precipitation method. Viral quantification was performed by RT-qPCR targeting the N1 and ORF1ab genes. A significant association (p < 0.05) was found between viral load in wastewater and reported cases of COVID-19 up to six days after sampling. During the whole study, two populated areas of the city were persistent hotspots of viral infection. The L452R mutation, suggestive of the presence of the Delta variant, was identified in the only sample where a complete genomic sequence could be obtained. Significant differences (p < 0.05) between the physicochemical conditions of the wastewater samples positive and negative for the virus were found. Our results support proof of concept that wastewater surveillance can serve as an early warning system for SARS-CoV-2 outbreaks, complementing public health surveillance in those regions where COVID-19 is currently underreported.
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COVID-19 , ARN Viral , SARS-CoV-2 , Aguas Residuales , Venezuela/epidemiología , COVID-19/epidemiología , COVID-19/virología , COVID-19/diagnóstico , Aguas Residuales/virología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Humanos , ARN Viral/genética , ARN Viral/análisis , Carga Viral , Monitoreo Epidemiológico Basado en Aguas ResidualesRESUMEN
The emergence of COVID-19 in 2020 significantly enhanced the application of wastewater monitoring for detecting SARS-CoV-2 circulation within communities. From October 2021 to October 2022, we collected 406 wastewater samples weekly from the Córdoba Central Pipeline Network (BG-WWTP) and six specific sewer manholes from sanitary zones (SZs). Following WHO guidelines, we processed samples and detected SARS-CoV-2 RNA and variants using real-time PCR. Monitoring at the SZ level allowed for the development of a viral activity flow map, pinpointing key areas of SARS-CoV-2 circulation and tracking its temporal spread and variant evolution. Our findings demonstrate that wastewater-based surveillance acts as a sensitive indicator of viral activity, detecting imminent increases in COVID-19 cases before they become evident in clinical data. This study highlights the effectiveness of targeted wastewater monitoring at both municipal and SZ levels in identifying viral hotspots and assessing community-wide circulation. Importantly, the data shows that environmental wastewater studies provide valuable insights into virus presence, independent of clinical COVID-19 case records, and offer a robust tool for adapting to future public health challenges.
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COVID-19 , SARS-CoV-2 , Monitoreo Epidemiológico Basado en Aguas Residuales , Aguas Residuales , COVID-19/epidemiología , Argentina/epidemiología , Aguas Residuales/virología , Humanos , ARN Viral/análisis , CiudadesRESUMEN
The textile mill is one of the most water-consuming industries. Wastewater production is very high, and among the main generated pollutants are dyes. In particular, jeans finishing, which is performed all over the world, generates wastewater with indigo dye that has to be eliminated before discharge. This work studies the biological treatment of this type of wastewater using native microorganisms, i.e., without the need for external seed sludge to start-up the process. Two strategies for starting up the biological treatment using laboratory sequencing batch reactors have been compared: the addition of seed sludge from a biological reactor of a wastewater treatment plant and the non-addition of seed sludge, which means that native microorganisms (those in wastewater coming from the industry facilities) are responsible for COD and color degradation. Special attention is paid to biomass shift in both reactors, analyzing both bacterial and fungal populations. Results yielded more than 90% of COD and color removal after 25 days in both reactors. MLSS increased in both reactors during the operation, reaching very similar values (around 1840 mg/L). Rozellomycota was the predominant phylum in the reactors. Concerning bacteria, Planctomycetota abundance increased considerably in both reactors, which shows the important role of these bacteria in the treatment. It can be concluded that the lower bacterial diversity in the native population in comparison with the seeded sludge was shifting to a higher microbial diversity during the process, achieving a similar microbial population in reactors. It implies that it is not necessary to either work with isolated cultures or seeded sludge, which leads to a simpler and more sustainable solution for textile wastewater treatment in areas all over the world.
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Biodegradación Ambiental , Colorantes , Eliminación de Residuos Líquidos , Aguas Residuales , Colorantes/metabolismo , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Industria Textil , Bacterias/metabolismo , Contaminantes Químicos del Agua/metabolismo , Aguas del AlcantarilladoRESUMEN
In the present study, nine Enterobacteriaceae species present in wastewater were isolated and identified, and loop-mediated isothermal amplification (LAMP) was developed for the detection of Enterobacteriaceae by designing primers based on the mcr-1, KPC, OXA-23, and VIM genes, which are recognized markers of antimicrobial resistance (AMR) transmission during microalgal bioremediation treatment. The developed assays successfully detected four strains positive for mcr-1 gene-asociated resistance (Acinetobacter baylyi, Klebsiella pneumoniae, Morganella morganii, and Serratia liquefaciens), three strains for KPC gene-associated resistance (Acinetobacter sp., Escherichia coli 15499, and Morganella morganii), seven strains for OXA-23 gene-associated resistance (Acinetobacter baylyi, Enterobacter hormaechi, Enterobacter cloacae, Escherichia coli 15922, Escherichia coli 51446, Morganella morganii, and Serratia liquefaciens), and three strains for resistance to the VIM gene-associated resistance (Acinetobacter baylyi, Acinetobacter sp., and Enterobacter hormaechi) from a single colony. A reduction in microbiological load of 93.6% was achieved at 15 colony-forming units (CFU) mL-1, utilizing EMB agar and LAMP values of 0.142 ± 0.011 for the mcr-1 gene, 0.212 ± 0.02 for the KPC gene, 0.233 ± 0.006 for the OXA-23 gene, and 0.219 ± 0.035 for the VIM gene. Furthermore, bioremediation efficiency values of 71.6% and 75% for total nitrogen and phosphorus, respectively, were observed at 72 h of treatment in open pond microalgal remediation systems (MRS). This study demonstrated that the LAMP technique is faster and more sensitive than traditional detection methods, such as CFU, for Enterobacteriaceae. Consequently, this method may be considered for the detection of microbiological quality indicators within the water treatment industry.