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During the COVID-19 pandemic, the Province of Ontario, Canada, launched a wastewater surveillance program to monitor SARS-CoV-2, inspired by the early work and successful forecasts of COVID-19 waves in the city of Ottawa, Ontario. This manuscript presents a dataset from January 1, 2021, to March 31, 2023, with RT-qPCR results for SARS-CoV-2 genes and PMMoV from 107 sites across all 34 public health units in Ontario, covering 72% of the province's and 26.2% of Canada's population. Sampling occurred 2-7 times weekly, including geographical coordinates, serviced populations, physico-chemical water characteristics, and flowrates. In doing so, this manuscript ensures data availability and metadata preservation to support future research and epidemic preparedness through detailed analyses and modeling. The dataset has been crucial for public health in tracking disease locally, especially with the rise of the Omicron variant and the decline in clinical testing, highlighting wastewater-based surveillance's role in estimating disease incidence in Ontario.
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COVID-19 , SARS-CoV-2 , Aguas Residuales , Ontario/epidemiología , COVID-19/epidemiología , Aguas Residuales/virología , Humanos , Pandemias , Carga ViralRESUMEN
This study investigated the impact of commonly used treatment chemicals on the morphology and molecular structure of microfibers (MFs) and microplastic films (MPFs) to determine whether significant changes could occur during wastewater treatment. MFs and MPFs were exposed to sodium hypochlorite (NaOCl), hydrogen peroxide (H2O2), calcium hydroxide (Ca(OH)2, pH 11), sodium hydroxide (NaOH, pH11), and hydrochloric acid (HCl, pH 3) at typical doses and exposure times used at wastewater treatment plants. Scanning electron microscopy (SEM) analysis and attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) were used to examine any morphological or chemical changes after the treatment. Morphological changes were observed in the form of cracks, and increased roughness was revealed in the SEM and 3-D surface images. The results showed that MFs were more resistant to surface degradation than MPFs. Moreover, intensity peaks of ATR-FTIR revealed some partial dislodgement of the bonds in both MFs and MPFs after chemical treatment, but the overall polymer structure remained intact. The changes that occur on the surface of MFs and MPFs during chemical treatment can impact their fate, removal, and transportation behavior both at the treatment plant and after discharge to the environment.
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Peróxido de Hidrógeno , Aguas Residuales , Plásticos , Microplásticos , Estructura Molecular , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
This study synthesized novel magnetic biochar (PCMN600) by KMnO4-NaOH combined modification using iron-containing pharmaceutical sludge to remove toxic metals from wastewater effectively. Various characterization experiments of engineered biochar showed that the modification process introduced ultrafine MnOx particles on the carbon surface and resulted in higher BET surface area and porosity along with more oxygen-containing surface functional groups. Batch adsorption studies indicated that the maximum adsorption capacities of PCMN600 for Pb2+, Cu2+ and Cd2+ were 181.82 mg/g, 30.03 mg/g and 27.47 mg/g, respectively, at a temperature of 25 °C and pH of 5.0, which were much higher than that of pristine biochar (26.46 mg/g, 6.56 mg/g and 6.40 mg/g). The adsorption datums of three toxic metal ions fitted well to the pseudo-second-order model and Langmuir isotherm, and the sorption mechanisms were identified as electrostatic attraction, ion exchange, surface complexation, cation-π interaction and precipitation. The strong magnetic properties of the engineered biochar endowed the adsorbent with remarkable reusability, and after five cycles of recycling, PCMN600 still retained nearly 80% of its initial adsorption capacities.
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Pollution of water sources by pathogens is a significant concern worldwide. In the present study, a pilot-scale once-through reactor was fabricated to investigate bacteria's inactivation and the degradation of organic matter present in municipal wastewater using an iron-mediated TiO2 catalyst in fixed mode. The catalyst was fabricated (in a spherical shape) using waste material such as foundry sand and fly ash and coated with TiO2 for a combined hybrid effect. The influence of H2O2 concentration and the flow rate of the reactor were examined. 4.1 log reductions of bacteria with 52% and 39% of BOD and COD reductions in 45 min of treatment were observed. The catalyst was also found to be highly durable, with only a 12.5% of reduction in catalyst activity observed after 200 recycles. Therefore, this pilot-scale research indicates the ability of waste materials to be employed as a practical approach for water disinfection applications.
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Aguas Residuales , Purificación del Agua , Desinfección , Peróxido de Hidrógeno , Titanio , AguaRESUMEN
Hybrid anaerobic-aerobic biological systems are an environmentally sustainable way of recovering bioenergy during the treatment of high-strength wastewaters and landfill leachate. This study provides a critical review of three major categories of anaerobic-aerobic processes such as conventional wetland, high-rate and integrated bioreactor systems applied for treatment of wastewaters and leachate. A comparative assessment of treatment mechanisms, critical operating parameters, bioreactor configurations, process control strategies, efficacies, and microbial dynamics of anaerobic-aerobic systems is provided. The review also explores the influence of wastewater composition on treatment performance, ammonium nitrogen removal efficacy, impact of mixing leachate, energy consumption, coupled bioenergy production and economic aspects of anaerobic-aerobic systems. Furthermore, the operational challenges, prospective modifications, and key future research directions are discussed. This review will provide in-depth understanding to develop sustainable engineering applications of anaerobic-aerobic processes for effective co-treatment of wastewaters and leachate.
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Aguas Residuales , Contaminantes Químicos del Agua , Anaerobiosis , Estudios Prospectivos , Integración de Sistemas , Reactores Biológicos , Contaminantes Químicos del Agua/análisis , NitrógenoRESUMEN
Early detection and monitoring of algal blooms and potentially toxic cyanobacteria in source waters are becoming increasingly important with rising climate change and industrialization. There is a growing need to measure the mixed microalgae cultures sensitively and accurately, as multiple algae species are present in natural source waters. This study investigated the detection of an equal concentration, mixed-culture of cyanobacteria (Microcystis aeruginosa) and a common green algae (Chlorella vulgaris) in water using UV-Vis spectrophotometry while employing longer pathlengths and derivative spectrophotometry to improve the detection limit. A strong linear relationship (R2 > 0.99) was found between the concentration and absorbance of the mixed-culture at 682 nm using 50 and 100 mm pathlengths. This study showed that the cyanobacterial (phycocyanin) peak could be separately identified in mixed-culture setting, while the chlorophyll peaks of both algae overlapped each other. The lowest detection limit of the mixed algal culture using traditional spectrophotometry and derivative spectrophotometry was calculated to be 25,997 cells/mL and 5505 cells/mL using a 100 mm cuvette pathlength. Lastly, the performance of mixed-culture and individual algal cultures were compared, and analyses were carried out to evaluate differences in slopes which can be used for quantification purposes. The results indicate that derivative spectrophotometry significantly improved the detection limit making the method potentially viable for the early detection of mixed algal cultures.
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Chlorella vulgaris , Cianobacterias , Microalgas , Microcystis , EspectrofotometríaRESUMEN
The penicillin industry produces a large amount of penicillin mycelial dreg (PMD), potentially causing severe environmental problems without proper treatment and disposal. To achieve the goals of PMD management, the present work explored the potential of PMD as a novel feedstock to produce biochar with very high adsorption performance. PMD was pyrolyzed at 400-800 °C to prepare biochars (PMD-BCs), and the physical and chemical properties were characterized using various methods. The adsorption capacities of Pb2+ on PMD-BC400, PMD-BC600, and PMD-BC800 were 37.04, 62.89, and 107.53 mg/g, respectively, at a temperature of 25 °C and pH of 5.0. The adsorption process of Pb2+ on PMD-BCs can be well described by the Langmuir model and pseudo-second-order model. Mineral precipitation, ion exchange, functional group complexation and Pb2+-π interaction were involved in the adsorption of Pb2+ on PMD-BCs. Moreover, mineral precipitation and ion exchange dominated Pb2+ sorption on PMD-BCs (84.71-92.73%). This study indicates the transition of PMD to biochar for Pb2+ adsorption is a promising method for PMD utilization.
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Pirólisis , Contaminantes Químicos del Agua , Plomo , Residuos Peligrosos , Penicilinas , Carbón Orgánico/química , Adsorción , Minerales , Cinética , Contaminantes Químicos del Agua/análisisRESUMEN
Improperdisposal of sludge will release heavy metals contained in sludge into soils or waters which could further move through the food chain, posing a risk to human health. Understanding the transformation and stabilization of heavy metals (HMs) during pyrolysis is of great value for safe disposal of sludge. Herein, municipal sewage sludge (MSS, organic-dominated) and pharmacy sludge (PS, inorganic-dominated) were pyrolyzed to investigate the effects of organic and inorganic components and temperature on the stabilization of HMs in sludges. The results showed that pyrolysis can promote the transition of HMs from mobile fractions to stable fractions. Compared to MSS and PS, the potential ecological risk index of biochar derived from MSS and PS decreased by 95.51% and 85.05%, respectively, after pyrolysis at 800 °C. The stabilization of HMs in MSS was mainly due to the complexation reactions between metals and amide functional groups (-CO-NH-) during pyrolysis. Moreover, the mechanism of HMs stabilization in PS lied in the formation of a stable crystal-structure such as copper iron oxide (Cu6Fe3O7) and copper iron phosphate (Cu2Fe5(PO4)6, Cu3Fe4(PO4)6) with iron-containing minerals after high-temperature pyrolysis. The results of this study indicated that the organic and inorganic components of sludge play different roles in the stabilization and transformation of HMs during pyrolysis, which provided a scientific basis for the ecotoxicity reduction of HMs and safe disposal of sludge.
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Metales Pesados , Pirólisis , Carbón Orgánico , Humanos , Hierro , Metales Pesados/análisis , Aguas del Alcantarillado/química , SueloRESUMEN
The study reports the applications of waste-derived visibly active Fe-TiO2 composite for the inactivation of E. coli present in water. The Fe/TiO2 catalyst holds remarkable properties of in situ hybrid effect via combining the TiO2-photocatalytic and photo-Fenton process in one system causing increased production of OHË. The quantum yield (QY) and reaction rate constant of this hybrid process at 40 W m-2 (UV-A irradiation) were found to be significantly higher in less treatment time (45 min) of E. coli inactivation. 23% synergy of in situ hybrid process over single processes was also observed. The increase in the K+ concentration at regular intervals confirmed the cell wall damage. In fully inactivated samples, no regrowth of cells was observed even after 24 and 48 h of dark study. Additionally, even after 100 recycles, the Fe/TiO2 catalyst demonstrated an exceptional durability/recyclability efficacy. The findings of this study highlight the potential of the hybrid process as a viable idea for post-treatment of the wastewater that can be implemented effectively in practice.
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Aguas Residuales , Purificación del Agua , Escherichia coli/efectos de la radiación , Peróxido de Hidrógeno , Hierro , Titanio , AguaRESUMEN
Because of the increased population density, high-risk behavior of young students, and lower vaccination rates, university campuses are considered hot spots for COVID-19 transmission. This study monitored the SARS-CoV-2 RNA levels in the wastewater of a Canadian university campus for a year to provide actionable information to safely manage COVID-19 on campus. Wastewater samples were collected from the campus sewer and residence buildings to identify changes, peaks, and hotspots and search for associations with campus events, social gatherings, long weekends, and holidays. Furthermore, the impact of wastewater parameters (total solids, volatile solids, temperature, pH, turbidity, and UV absorbance) on SARS-CoV-2 detection was investigated, and the efficiency of ultrafiltration and centrifugation concentration methods were compared. RT-qPCR was used for detecting SARS-CoV-2 RNA. Wastewater signals largely correlated positively with the clinically confirmed COVID-19 cases on campus. Long weekends and holidays were often followed by increased viral signals, and the implementation of lockdowns quickly decreased the case numbers. In spite of online teaching and restricted access to campus, the university represented a microcosm of the city and mirrored the same trends. Results indicated that the centrifugation concentration method was more sensitive for wastewater with high solids content and that the ultrafiltration concentration method was more sensitive for wastewater with low solids content. Wastewater characteristics collected from the buildings and the campus sewer were different. Statistical analysis was performed to manifest the observations. Overall, wastewater surveillance provided actionable information and was also able to bring high-risk factors and events to the attention of decision-makers, enabling timely corrective measures.
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The growing use of silver nanoparticles (AgNPs) in personal care products and clothing has increased their concentrations in wastewater and subsequently in sludge raising concerns about their fate and toxicity during wastewater treatment and after land application of sludge. This research investigated the fate and removal of AgNPs during chemical conditioning of anaerobically digested sludge and their impact on soil bacteria and health after land application. Ferric chloride (FeCl3), alum (Al2 (SO4)3 ⢠(14-18) H2O), and synthetic (polyacrylamide) polymer were used for sludge conditioning. All conditioners effectively removed AgNPs from the liquid phase and concentrated them in sludge solids. Concentration analyses showed that out of 53.0 mg/L of silver in the sludge, only 0.1 to 0.003 mg/L of silver remained in the sludge supernatant after conditioning and 12 to 20% of this value were particulates. Morphological analyses also showed that AgNPs went through physical, chemical, and morphological changes in sludge that were not observed in nanopure water and the resulting floc structures and the incorporation of nanoparticles were different for each conditioner. The impact of conditioned AgNPs on the biological activities of soil was evaluated by investigating its impact on the presence of five important phyla (Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria). The results showed that AgNPs at a concentration of 20 mg AgNPs/g soil had a minimal impact on the presence and diversity of the assessed phyla. Also, using different chemicals for sludge conditioning resulted in different growth behavior of studied phyla. This study provides new insight into how the presence of AgNPs and different chemicals used for sludge conditioning might impact the soil biological activities and hence plant growth. The study also provides a solid basis for further research in the risk assessment of nanoparticle toxicity in biosolids amended soils.
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Nanopartículas del Metal , Aguas del Alcantarillado , Plata/análisis , Suelo , Aguas ResidualesRESUMEN
This study investigated the impact of lime stabilization on the fate and transformation of AgNPs. It also evaluated the changes in the population and diversity of the five most relevant bacterial phyla in soil after applying lime-stabilized sludge containing AgNPs. The study was performed by spiking an environmentally relevant concentration of AgNPs (2 mg AgNPs/g TS) in sludge, applying lime stabilization to increase pH to above 12 for two hours, and applying lime-treated sludge to soil samples. Transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) were used to investigate the morphological and compositional changes of AgNPs during lime stabilization. After the application of lime stabilized sludge to the soil, soil samples were periodically analyzed for total genomic DNA and changes in bacterial phyla diversity using quantitative polymerase chain reaction (qPCR). The results showed that lime treatment effectively removed AgNPs from the aqueous phase, and AgNPs were deposited on the lime molecules. The results revealed that AgNPs did not significantly impact the presence and diversity of the assessed phyla in the soil. However, lime stabilized sludge with AgNPs affected the abundance of each phylum over time. No significant effects on the soil total organic carbon (TOC), heterotrophic plate count (HPC), and percentage of the live cells were observed.
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Cryptosporidium spp. are one of the most important waterborne pathogens worldwide and a leading cause of mortality from waterborne gastrointestinal diseases. Detection of Cryptosporidium spp. in water can be very challenging due to their low numbers and the complexity of the water matrix. This review describes the biology of Cryptosporidium spp. and current methods used in their detection with a focus on C. parvum and C. hominis. Among the methods discussed and compared are microscopy, immunology-based methods using monoclonal antibodies, molecular methods including PCR (polymerase chain reaction)-based assays, and emerging aptamer-based methods. These methods have different capabilities and limitations, but one common challenge is the need for better sensitivity and specificity, particularly in the presence of contaminants. The application of DNA aptamers in the detection of Cryptosporidium spp. oocysts shows promise in overcoming these challenges, and there will likely be significant developments in aptamer-based sensors in the near future.
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Criptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Animales , Cryptosporidium/genética , Oocistos , AguaRESUMEN
Many methods have been reported to detect Cryptosporidium parvum (C. parvum) oocysts in the water environment using monoclonal antibodies. Herein, we report the use of DNA aptamers as an alternative ligand. We present the highly sensitive detection of C. parvum oocysts in wastewater samples based on aptamer-conjugated magnetic beads. A previously selected DNA aptamer (R4-6) that binds to C. parvum oocysts with high affinity and selectivity was rationally truncated into two minimer aptamers (Min_Crypto1 and Min_Crypto2), and conjugated to micro-magnetic beads. In flow cytometry tests with phosphate buffer, river water, and wastewater samples, both the minimers showed improved affinity and specificity toward C. parvum oocysts than the parent R4-6. Moreover, Min_Crypto2 showed higher affinity to its target than the parent aptamer when testing in wastewater, indicating superior binding properties in a complex matrix. Using a fluorescence microplate-based assay, and when incubated with different numbers of oocysts, Min_Crypto2 showed a limit of detection as low as 5 C. parvum oocysts in 300 µL of wastewater. Results described here indicate that Min_Crypto2 has superior specificity and sensitivity for the detection of C. parvum oocysts, and has a strong potential to be used successfully in a sensor.
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Criptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Animales , Fenómenos Magnéticos , Oocistos , Ríos , Aguas Residuales , AguaRESUMEN
This study evaluated the performance of high-density polyethylene (HDPE), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyvinylchloride (PVC), polypropylene (PP), polyvinylidene fluoride (PVDF) and polymethyl methacrylate (acrylic) when used as a support media in anaerobic attached-growth wastewater treatment systems. A combination of physical and chemical (total solids, protein, phosphorus, ammonia, chemical oxygen demand) methods, environmental scanning electron microscopy (ESEM) and Live/Dead viability assay) and genetic sequencing over a period of 81 days was used to provide an in-depth understanding of the impact of different polymer materials on biofilm formation, bacteria population, and wastewater treatment performance. The results showed that hydrophobic polymeric materials (i.e., PP and PVDF) promoted initial cell adhesion and biofilm formation (<16 days) better than the hydrophilic (i.e., ABS and HDPE) polymeric materials. However, under longer-term and steady-state operation (after 81 days), the hydrophilic materials demonstrated larger mature biofilm quantities and better wastewater treatment performance. The sequencing data showed biofilm bacterial community structures of the ABS and HDPE to be significantly different compared to the other polymeric materials tested. The data showed a positive correlation as well between the phyla present on the ABS and HDPE and COD removal. These results suggest that the type of polymeric material play an important role in biofilm development, bacterial population diversity, and wastewater treatment performance for anaerobic fixed-film systems, and ABS and HDPE performed better than the widely used PVC in the industry.
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Biopelículas , Purificación del Agua , Anaerobiosis , Bacterias/genética , Reactores Biológicos , Fósforo , Eliminación de Residuos LíquidosRESUMEN
This study investigated whether 2 and 30 mg AgNPs or CuONPs/g TS present in treated sludge (biosolids) may impact the soil health by monitoring the soil characteristics and soil bacterial community for 105 days after the application of biosolids. AgNPs or CuONPs/g TS were first anaerobically digested with mixed primary and secondary sludge rather than adding pristine nanoparticles to biosolids directly. Both environmentally relevant (under the USEPA ceiling concentration limits) and high concentrations of AgNPs and CuONPs were tested. Soil tests included TOC, TN, TP, pH, cell viability and heterotrophic plate counts (HPC). Metagenomic data was generated by high-throughput sequencing of the 16S rRNA gene to explore bacterial populations and diversity. AgNPs and CuONPs at 2 and 30 mg NPs/g TS of sludge could impact soil health factors such as bacterial diversity, community structure, and the population of plant growth-promoting rhizobacteria (PGPR). The population of the highly abundant bacteria that have important physiological roles in soil decreased, while the less important bacteria for soil function were able to thrive. CuONPs exhibited a higher level of toxicity than the AgNPs at both phylum and genus taxonomic levels, and the HPC decreased with higher concentrations of AgNPs and CuONPs. Initially, most of the studied phyla abundance was affected, but the control and other reactors approached similar levels by the end of the experiments, which may be explained by the decrease in toxicity due to the transformation of nanoparticles and the defence mechanisms of bacteria, and indicates the need for long-term field studies.
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Nanopartículas del Metal , Contaminantes del Suelo , Bacterias/genética , Biosólidos , Cobre/toxicidad , Nanopartículas del Metal/toxicidad , Óxidos , ARN Ribosómico 16S , Plata/análisis , Plata/toxicidad , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidadRESUMEN
Domestic wastewater (WW) contains a large number of pathogenic viruses that are not significantly reduced in most WW treatment processes and are found in high numbers in the effluent of conventionally disinfected WW. In this study, secondary WW effluent bench-scale disinfection efficacy experiments with two different peracetic acid (PAA) formulations (15 and 22% peracetic acid) and low-pressure ultraviolet irradiation (LP-UV) were carried out using Coxsackievirus B3 (CVB3) as a clinically relevant surrogate for enteric viruses and Escherichia coli (E. coli) as the disinfection efficacy control. Efficacy experiments were done in a test matrix of medium-pressure UV (MP-UV) decontaminated secondary WW effluent under representative PAA doses and LP-UV fluences used at wastewater treatment plants (WWTP). Membrane filtration technique was used to determine Log10 CFU reductions of E. coli and a tissue culture infectious dose 50% assay (TCID50) for Log10 TCID50 reduction of CVB3. The CVB3 proved to be quite resistant to PAA with ≤1 Log10 TCID50 reduction to concentrations ≤50 mg/L at a contact time of 15 min, and highly susceptible to LP-UV at 20 mJ/cm2. Concurrent use of both formulations of 3 mg/L PAA with 20 mJ/cm2 LP-UV achieved â¼4 Log10 TCID50 reduction. The E. coli results showed Ë5 Log10 CFU reductions at a contact time of 15 min with both 3 mg/L PAA formulations, 20 mJ/cm2 LP-UV treatment alone, and combined with both 1.5 mg/L PAA formulations. The E. coli efficacy data were consistent with that reported in the literature and showed to be comparable to conventional chlorine disinfection. The CVB3 efficacy data has shown that PAA alone may not be suitable for the reduction of enteric viruses in secondary wastewater effluent, but this is also the case for chlorine-based disinfectants. The results from this study showed that the use of PAA with LP-UV at reasonable concentrations (1.5 mg/L) and fluence (20 mJ/cm2) can significantly reduce the PAA use and meet wastewater disinfection goals for both E. coli and CVs. However, the concurrent use of PAA with LP-UV did not lead to significant synergy in disinfection efficacy in wastewater.
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Desinfectantes , Ácido Peracético , Desinfección , Escherichia coli , Rayos Ultravioleta , Aguas ResidualesRESUMEN
There is increasing interest in the environmental fate and effects of engineered nanomaterials due to their ubiquitous use in consumer products. In particular, given the mounting evidence that dramatic transformations can occur to a nanomaterial throughout its product lifecycle, the appropriateness of using pristine nanomaterials in environmental testing is being questioned. Using a combination of transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma-mass spectrometry (ICP-MS), this work examines the morphological and compositional effects of conditions mimicking a typical lifecycle of a nano-enabled product, from the production of the silver nanoparticle (AgNP)-laden textiles, through its use, laundering, and then finally, its leaching and incubation in the wastewater collection system. These simulated weathering conditions showed evidence for the transformation of AgNPs into AgCl and Ag2S. Incubation in raw wastewater had the most dramatic effect on the AgNPs in terms of transformation, no matter what initial weathering was applied to the NPs prior to incubation. However, despite extensive transformation noted, AgNPs were still present within all the samples after the use scenarios.
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This research investigated the removal capacity of polymeric sub-micron ion-exchange resins (SMR) for removal of lead, copper, zinc, and nickel from natural waters in competition with natural organic matter (NOM). Polymeric SMR particles were created and tested to ensure that they were adequately dispersed in the solution. They removed little NOM (10% or less) from river water and wastewater, indicating that competition from NOM was not a major concern. SMR were able to remove 82%±0.2% of lead, 46%±0.6% of copper, 55%±20% of zinc, and 17%±2% of nickel from river water spiked with 500µg/L of each. Similarly, in wastewater, they were able to remove 86%±0.1% of lead, 38%±0.8% of copper, 28%±1% of zinc, and 11%±1% of nickel.
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Resinas de Intercambio Iónico/química , Metales/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Metales/química , Contaminantes Químicos del Agua/químicaRESUMEN
Natural organic matter (NOM), present in natural waters and wastewater, decreases adsorption of micropollutants, increasing treatment costs. This research investigated mechanisms of competition for non-imprinted polymers (NIPs) and activated carbon with humic acid and wastewater. Three different types of activated carbons (Norit PAC 200, Darco KB-M, and Darco S-51) were used for comparison with the NIP. The lower surface area and micropore to mesopore ratio of the NIP led to decreased adsorption capacity in comparison to the activated carbons. In addition, experiments were conducted for single-solute adsorption of Methylene Blue (MB) dye, simultaneous adsorption with humic acid and wastewater, and pre-loading with humic acid and wastewater followed by adsorption of MB dye using NIP and Norit PAC 200. Both the NIP and PAC 200 showed significant decreases of 27% for NIP (p=0.087) and 29% for PAC 200 (p=0.096) during simultaneous exposure to humic acid and MB dye. There was no corresponding decrease for NIP or PAC 200 pre-loaded with humic acid and then exposed to MB. In fact, for PAC 200, the adsorption capacity of the activated carbon increased when it was pre-loaded with humic acid by 39% (p=0.0005). For wastewater, the NIP showed no significant increase or decrease in adsorption capacity during either simultaneous exposure or pre-loading. The adsorption capacity of PAC 200 increased by 40% (p=0.001) for simultaneous exposure to wastewater and MB. Pre-loading with wastewater had no effect on MB adsorption by PAC 200.