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Background: Although there are many uses for metal–organic framework (MOF) based nanocomposites, research shows that these materials have received a lot of interest in the field of water treatment, namely in the photodegradation of water contaminants, and disinfection of some pathogenic bacteria and fungi. This is brought on by excessive water pollution, a lack of available water, low-quality drinking water, and the emergence of persistent micro-pollutants in water bodies. Photocatalytic methods may be used to remove most water contaminants, and pathogenic microbes, and MOF is an excellent modifying and supporting material for photocatalytic degradation. Methods: This work involved the fabrication of a unique Cu-MOF based nanocomposite that was exposed to gamma radiation. The nanocomposite was subsequently employed for photocatalytic degradation and as an antimicrobial agent against certain harmful bacteria and fungi. The produced Cu-MOf nanocomposite was identified by XRD, SEM, and EDX. Growth curve analysis, UV lighting impact, and antibiofilm potential have been carried out to check antimicrobial potential. Additionally, the membrane leakage test was used to determine the mechanism of the antimicrobial action. In an experimental investigation of photocatalytic activity, a 50 mL aqueous solution including 10.0 ppm of Rhodamine B (RB) was used to solubilize 10 mg of Cu-MOF. It has been investigated how pH and starting concentration affect RB elimination by Cu-MOF. Ultimately, RB elimination mechanism and kinetic investigations have been carried out. Results: SEM images from the characterization techniques demonstrated the fact that the Cu-MOF was synthesized effectively and exhibited the Cu-MOF layers' flake-like form. Uneven clusters of rods make up each stratum. The primary peaks in the Cu-MOF's diffraction pattern were found at 2θ values of 8.75◦, 14.83◦, 17.75◦, 21.04◦, 22.17◦, 23.31◦, 25.41◦, and 26.38◦, according to the XRD data. After 135 min of UV irradiation, only 8% of RB had undergone photolytic destruction. On the other hand, the elimination resulting from adsorption during a 30-min period without light was around 16%. Conversely, after 135 min, Cu-MOF's photocatalytic breakdown of RB with UV light reached 81.3%. At pH 9.0, the greatest removal of RB at equilibrium was found, and when the amount of photocatalyst rose from 5 to 20 mg, the removal efficiency improved as well. The most sensitive organism to the synthesized Cu-MOF, according to antimicrobial data, was Candida albicans, with a documented MIC value of 62.5 µg mL−1 and antibacterial ZOI as 32.5 mm after 1000 ppm treatment. Cu-MOF also showed the same MIC (62.5 µg mL−1) values against Staphylococcus aureus and Escherichia coli, and 35.0 and 32.0 mm ZOI after 1000 ppm treatment, respectively. Ultimately, it was found that Cu-MOF (1000 µg/mL) after having undergone gamma irradiation (100.0 kGy) was more effective against S. aureus (42.5 mm ZOI) and E. coli (38.0 mm ZOI). Conclusion: From the obtained results, the synthesized MOF nanocomposites had promising catalytic degradation of RB dye and high antimicrobial potential which encouraging their use in wastewater treatment against some pathogenic microbes and polluted dyes. Due to the exceptional physicochemical characteristics of MOF nanocomposites, it is possible to create and modify photocatalytic nanocomposites in a way that improves their recovery, efficiency, and recyclability. [ABSTRACT FROM AUTHOR]

[Display omitted] • The catalytic mechanism and material preparation based on the piezoelectric effect. • The application of the piezoelectric effect in wastewater purification is expounded. • The development of the piezoelectric effect-assisted water purification technology. • The challenges and prospects of the piezoelectric effect in wastewater purification. The demands of human life and industrial activities result in a significant influx of toxic contaminants into aquatic ecosystems. In particular, organic pollutants such as antibiotics and dye molecules, bacteria, and heavy metal ions are represented, posing a severe risk to the health and continued existence of living organisms. The method of removing pollutants from water bodies by utilizing the principle of the piezoelectric effect in combination with chemical catalytic processes is superior to other wastewater purification technologies because it can collect water energy, mechanical energy, etc. to achieve cleanliness and high removal efficiency. Herein, we briefly introduced the piezoelectric mechanisms and then reviewed the latest advances in the design and synthesis of piezoelectric materials, followed by a summary of applications based on the principle of piezoelectric effect to degrade pollutants in water for wastewater purification. Moreover, water purification technologies incorporating the piezoelectric effect, including piezoelectric effect-assisted membrane filtration, activation of persulfate, and battery electrocatalysis are elaborated. Finally, future challenges and research directions for the piezoelectric effect are proposed. [ABSTRACT FROM AUTHOR]

Combinations of metal disinfectants (i.e., silver and copper) with chlorine in doses that meet the World Health Organization guidelines for drinking water operate synergistically to provide superior drinking water disinfection across a wide range of pathogens. Moreover, the combination of disinfectants allows for lower chlorine levels and a less objectionable taste and odor to the treated water (some people can taste or smell chlorine at concentrations as low as 300 μg/L). Towards chlorine-releasing materials for combination with silver- or copper-releasing materials in point-of-use water disinfection, N-chloramine containing polymer gels were developed and their potential for E. coli bacteria inactivation was assessed in deionized water that contained salts to simulate groundwater. Following the chlorination of gels containing chloramine precursors, these gels capably inactivated E. coli, achieving log10 reductions—depending on the gel mass—ranging from 1.1 to 4.5. While chlorine released from the gels was not spectroscopically detected, free chlorine solutions inactivated E. coli in a concentration-dependent way, with 5 and 20 μg/L Cl2 yielding log10 reductions of 0.43 and 1.69, respectively, suggesting that low levels of chlorine, below both the limit of detection of spectroscopic assays (ca. 40 μg/L Cl2) and levels known to create adverse taste and smell, are sufficient to inactivate bacteria. Unchlorinated gels or chlorinated control styrene gels (without chloramine precursor) did not inactivate bacteria, suggesting that disinfection did not come from the precursor or from chlorine trapped in the gels after chlorination. In addition, these gels were evaluated together with the MadiDrop (MD, a commercial silver-ceramic tablet) and a copper screen that release silver and copper disinfectants, respectively. Combinations of the gel and MD produced E. coli inactivation close to 2-log10 reduction, with the combination, gels alone, and MD alone achieving 1.86-, 1.10-, and 0.69-log10 reduction, respectively. When the gels were combined with the copper screen, however, neither an increase nor a decrease in bacterial reduction was observed compared to that achieved with the gels alone. The laboratory results in this study are promising and suggest the potential for chloramine-functionalized gels to serve as an alternative to existing commercial chlorine-based POU technologies and in combination with silver-based POU technologies. [ABSTRACT FROM AUTHOR]

Chlorine species play a crucial role as precursors to Cl radicals, which can significantly impact the atmospheric oxidation capacity and influence the levels of trace gases related to climate and air quality. Several studies have established a chlorine emission inventory in China in recent years, but the emission remains uncertain and requires further investigation. The Anthropogenic Chlorine Emission Inventory for China (ACEIC) was the first chlorine emission inventory for China based on local data developed in our previous study, which only includes the emissions from coal combustion and waste incineration. In this study, we updated this inventory to include data for a more recent year (2019) and expanded the range of species considered (HCl, fine particulate Cl - , Cl 2 , and hypochlorous acid (HOCl)) and the number of anthropogenic sources (41 specific sources). Compared with previous studies, this updated inventory considered more anthropogenic sources, used more localized emission factors, and adopted more refined estimation methods. The total emissions of HCl, fine particulate Cl - , Cl 2 , and HOCl in mainland China for the year 2019 were estimated to be 361 (- 18 % to 27 %), 174 (- 27 % to 59 %), 18 (- 10 % to 15 %), and 79 (- 12 % to 18 %) Gg, respectively. To facilitate analysis, we aggregated the chlorine emissions from various sources into five economic sectors: power, industry, residential, agriculture, and biomass burning. HCl emissions were primarily derived from the industry (43 %), biomass burning (38 %), and residential (13 %) sectors. The biomass burning and industry sectors accounted for 74 % and 19 % of the fine particulate Cl - emissions, respectively. Residential and industry sectors contributed 61 % and 29 % of the total Cl 2 emissions. HOCl emissions were predominantly from the residential sector, constituting 90 % of the total emissions. Notably, the usage of chlorine-containing disinfectants was identified as the most significant source of Cl 2 and HOCl emissions in the residential sector. Geographically, regions with high HCl and fine particulate Cl - emissions were found in the North China Plain, northeastern China, central China, and the Yangtze River Delta, whereas the Pearl River Delta, Yangtze River Delta, and Beijing–Tianjin–Hebei regions exhibited elevated levels of Cl 2 and HOCl emissions. Regarding monthly variation, emissions of HCl and fine particulate Cl - were higher during early spring (February to April) and winter (December to January) due to intensified agricultural activities, while Cl 2 and HOCl emissions were higher in the summer months due to increased demand for water disinfection. We incorporated this emission inventory into the chemical transport model and found the simulated concentrations of chlorine species agreed reasonably well with the observations, which suggested the relatively faithful estimations of their emissions. This updated inventory contributes to a better understanding of anthropogenic sources of chlorine species and can aid in the formulation of emission control strategies to mitigate secondary pollution in China. [ABSTRACT FROM AUTHOR]

A manganese dioxide (MnO2)/bamboo carbon (BC) composite was prepared using hydrothermal and impregnation methods and used for the capacitive desalination (CDI) and disinfection of water. The results showed that these composites had fast Na+ ion exchange and charge transfer properties. During the CDI process, these composites' electrodes exhibited good cycle stability and electrosorption capacity (4.09 mg/g) and an excellent bactericidal effect. These carbon-based composite electrodes' bactericidal rate for Escherichia coli could reach 99.99% within 180 min; therefore, they had good performance and are a good choice for high-performance deionization applications. [ABSTRACT FROM AUTHOR]

Increasing climate‐related extreme weather events and conflicts hinder safe water sanitation for vulnerable populations. In developing areas, centralized water systems are impractical due to high costs and poor infrastructure. Thus, technologies utilizing renewable energy like solar and mechanical energy for water treatment hold promise. It is critical to develop photocatalysts and piezoelectric/triboelectric catalysts that capture solar energy as well as mechanical energy to generate disinfectants to maximize energy utilization. The latest advancements in principles, materials, and processes utilizing solar and mechanical energy for water disinfection are highlighted in this review. First, we elucidate both direct and indirect mechanisms of sunlight‐mediated water disinfection, discuss the evolution of photocatalysts from simple UV absorption to visible‐light utilization, and even near‐infrared light exploitation to enhance solar spectrum utilization efficiency. Furthermore, we delve into the fundamental principles of piezoelectricity and triboelectricity relying on mechanical energy conversion as well as summarize the development of piezo/triboelectric catalysts from being driven by high‐frequency energy to utilizing low‐frequency mechanical energy from the environment. Finally, challenges and directions for efficient systems are outlined to inspire rational design strategies and accelerate the production of superior catalytic systems applicable across a broad range. [ABSTRACT FROM AUTHOR]

Inorganic arsenic (As), a known carcinogen and major contaminant in drinking water, affects over 140 million people globally, with levels exceeding the World Health Organization's (WHO) guidelines of 10 μg L−1. Developing innovative technologies for effluent handling and decontaminating polluted water is critical. This paper summarizes the fundamental characteristics of chitosan-embedded composites for As adsorption from water. The primary challenge in selectively removing As ions is the presence of phosphate, which is chemically similar to As(V). This study evaluates and summarizes innovative As adsorbents based on chitosan and its composite modifications, focusing on factors influencing their adsorption affinity. The kinetics, isotherms, column models, and thermodynamic aspects of the sorption processes were also explored. Finally, the adsorption process and implications of functionalized chitosan for wastewater treatment were analyzed. There have been minimal developments in water disinfection using metal-biopolymer composites for environmental purposes. This field of study offers numerous research opportunities to expand the use of biopolymer composites as detoxifying materials and to gain deeper insights into the foundations of biopolymer composite adsorbents, which merit further investigation to enhance adsorbent stability. [ABSTRACT FROM AUTHOR]

[Display omitted] Exploring highly efficient ultrasound-triggered catalysts is pivotal for various areas. Herein, we presented that Ba2+ doped brookite TiO 2 nanorod (TiO 2 : Ba) with polarization-induced charge separation is a candidate. The replacement of Ba2+ for Ti4+ not only induced significant lattice distortion to induce polarization but also created oxygen vacancy defects for facilitating the charge separation, leading to high-efficiency reactive oxygen species (ROS) evolution in the piezo-catalytic processes. Furthermore, the piezocatalytic ability to degrade dye wastewater demonstrates a rate constant of 0.172 min-1 and achieves a 100 % antibacterial rate at a low dose for eliminating E. coli. This study advances that doping can induce piezoelectricity and reveals that lattice distortion-induced polarization and vacancy defects engineering can improve ROS production, which might impact applications such as water disinfection and sonodynamic therapy. [ABSTRACT FROM AUTHOR]

Monitoring organic pollutants in rainwater is important to understand relations between air pollutants and water safety. Non-targeted liquid chromatography–mass spectrometry (LC–MS) is a powerful tool but because of big differences of pollutants in polarity, ionization efficiency, and low concentrations, it is challenging to detect all pollutants in a single analysis. Chemical derivatization is a widely adapted strategy to fractionate complex samples with enhanced sensitivity and selectivity. Herein, we propose the usage of dansylation as a chemical derivatization method to improve both LC retention and MS ionization of organic pollutants containing amine, hydroxyl, and carboxyl for non-targeted LC–MS analysis. We first evaluated the labeling coverage of dansylation to organic pollutants in water matrix. Using dansyl chloride (DnsCl) and dansyl hydrazine (DnsHz) to label 100 amine- and hydroxyl-containing compounds and 100 carboxyl compounds, respectively, we found DnsCl and DnsHz had over 60% labeling coverage for 8 categories of compounds. Then dansylation was applied to label the rainwater, source water, disinfected rainwater, and drinking water samples. To facilitate the annotation of dansylated compounds, we also established a web-based tool termed DansylFinder. Using DansylFinder, 3889, 5813, 6077, and 4050 tentative annotations were found in rainwater, source water, disinfected rainwater, and drinking water samples by dansylation-based non-targeted LC-HRMS analysis. Four hundred fifty four were persistently detected in all water samples, suggesting significant organic overlaps of the four water samples. In addition, two degradation pathways reported in drinking water disinfection process were also detected in disinfected rainwater, suggesting rainwater is a potential path for air pollutants to infiltrate drinking water system. [ABSTRACT FROM AUTHOR]

An analysis of the physical and chemical phenomena accompanying electrical discharges is carried out, and the main factors influencing microorganisms' abatement are studied. The similarity of the cavitation processes in water systems induced by underwater electric discharges and ultrasound is experimentally demonstrated. The characteristic features of electrical discharge in the cavitation mode, providing effective water disinfection with electric discharges with a significantly reduced amount of active chlorine, are identified in order of importance. The inactivation of microorganisms is intensified, firstly, by the generation of chemically active particles from the water medium itself, due to the integral action of the electro-discharge cavitation of the whole treated volume, and by local shock waves, acoustic flows, and ultraviolet radiation in the area near the cavitating bubbles. The main advantages of electric discharge cavitation over ultrasonic range are the wider range of high-frequency acoustic radiation inherent in an electric discharge, the high intensity and power of the cavitation processes, and the possibility of a significant increase in the volume of disinfected liquid. This study allows for a better understanding and prediction of the bacterial effects that occur during a high-voltage underwater electrical discharge. [ABSTRACT FROM AUTHOR]

Residents of remote areas in the Amazon often lack access to a water supply system and thus need to produce their potable water at home. This study examined the efficacy of household water treatments traditionally used by these communities to treat rainwater and river water, their predominant water sources. Samples of untreated, treated, and stored drinking water were collected from 18 households in three communities in Central Amazon, Amazonas State, Brazil. We describe the materials and practices involved and traditionally used in each treatment technique - cloth filtration (water straining), chlorination, and sedimentation, and their efficiency. In the samples we evaluate water quality analyses, as free chlorine, color, coliforms, and turbidity. The treatment steps for the separation of solids in river water were effective only for removing turbidity and apparent color. Straining river water after sedimentation had no relevant effect on water quality. Chlorination of rainwater was efficient in inactivating Escherichia coli; however, all samples showed some level of contamination by E. coli. We found a significant difference (p < 0.05) between untreated and treated river water turbidity, reduced by up to 22%. Untreated rain and river waters showed similar levels of microbiological contamination, close to 3.5 log CFU/100 mL of E. coli. Chlorine effectively removed microbiological contaminants in rainwater (median removal of 100, 44.5% of samples with <1 CFU/100 mL). Yet, this treatment was less effective for river water (94% median removal, with 11% of samples with <100 CFU/100 mL and only 5.5% with <1 CFU/100 mL found in treated water), showing a significant reduction in both cases when the Wilcoxon test was applied. Sodium hypochlorite treatment showed the best results among the techniques evaluated in this study. It can be used in remote areas where rainwater is available for consumption. Microorganism concentration increased after water underwent water straining and sedimentation processes. These results suggest that the improper handling of water containers and materials used during treatment processes leads to contamination of water. Thus, more robust outreach and educational efforts are recommended to improve remote communities' water collection, treatment, and storage practices. [ABSTRACT FROM AUTHOR]

Chlorine is widely used for sterilization and disinfection of water, but the presence of excess residual chlorine in water poses a substantial threat to human health. At present, there is no portable device which can achieve accurate, rapid, low-cost, and convenient detection of residual chlorine in water. Therefore, it is necessary to develop a device that can perform accurate, rapid, low-cost, and convenient detection of residual chlorine in water. In this study, a portable residual chlorine detection device was developed. A microfluidic chip was studied to achieve efficient mixing of two-phase flow. This microfluidic chip was used for rapid mixing of reagents in the portable residual chlorine detection device, reducing the consumption of reagents, detection time, and device volume. A deep learning algorithm was proposed for predicting residual chlorine concentration in water, achieving precise detection. Firstly, the microfluidic chip structure for detecting mixed reagents was optimized, and the microfluidic chip was fabricated by a 3D-printing method. Secondly, a deep learning (LS-BP) algorithm was constructed and proposed for predicting residual chlorine concentration in water, which can realize dual-channel signal reading. Thirdly, the corresponding portable residual chlorine detection device was developed, and the detection device was compared with residual chlorine detection devices and methods in other studies. The comparison results indicate that the portable residual chlorine detection device has high detection accuracy, fast detection speed, low cost, and good convenience. The excellent performance of the portable residual chlorine detection device makes it suitable for detecting residual chlorine in drinking water, swimming pool water, aquaculture and other fields. [ABSTRACT FROM AUTHOR]

Objectives: Compare the tensile strength and rupture elongation of room temperature vulcanizing silicone (RTV), heat temperature vulcanizing silicone (HTV) and 3% SiO2 reinforced RTV and HTV following disinfection with various agents. Materials and Methods: According to ASTM D412, 384 samples were fabricated using HTV, RTV, RTV and HTV reinforced with 3% SiO2 nanoparticles. The control group received no disinfection treatment, while the other samples were disinfected for 10 minutes using neutral soap, 4% chlorhexidine, and ozone water, three times a day for 60 days. Additionally, accelerated aging was carried out for 252,504,1008 hours. Tensile strength and rupture elongation were assessed using a universal testing machine at 500 mm/min speed, and the mean values were analyzed using two-way ANOVA and Tukey HSD test (P<0.05). Results: The mean value of tensile strength of RTV (2.96 ± 0.41), 3%SiO2 RTV (3.26 ±0.33), HTV (3.30 ±0.36),3% SiO2 HTV (4.07 ±0.85) MPa which was statistically significant for control, neutral soap and 4% chlorhexidine at 252,504, 1008 hours of aging. (P <0.05). The percentage of elongation of RTV (545 ±29.2),3%SiO2 RTV (617 ±30.5), HTV (735 ±48.7),3% SiO2 HTV (801 ±55.7) which was statically significant for control, neutral soap, 4% chlorhexidine and Ozone water for 252, 504, 1008 hours of aging. (P <0.05). Conclusion: The HTV silicone showed more tensile strength and rupture elongation compared to HTV, RTV and RTV silicones reinforced with 3% SiO2 nanoparticles. Ozone water disinfection had least effect on tensile strength and rupture elongation of maxillo-facial silicone compared to other disinfectant. [ABSTRACT FROM AUTHOR]

LaOCl belongs to one kind of promising solid electrolyte for chlorine-ion batteries due to its excellent electric insulation performance and special layered structure. However, LaOCl still suffers from poor chlorine-ion conductivity. Then, we proposed microstructure modulation of LaOCl to solve this problem based on Al doping method. Firstly, we carried out first-principles and ab-initio molecular dynamics (AIMD) calculations to investigate the internal relation among structure stability, chlorine-ion conductivity and related physicochemical properties of Al doped LaOCl(La 1- x Al x OCl). It is found that La 0.75 Al 0.25 OCl not only possesses most stable structure but also demonstrates the best ductility. Moreover, La 0.75 Al 0.25 OCl also possesses much lower chlorine-ion diffusion energy barrier than LaOCl(0.40 eV vs.0.78 eV) and its chlorine-ion conductivity goes as high as 5.4 × 10−3 S/cm at 300K. This is attributed to the optimal reconstruction of La–Cl coordination structure induced by Al dopant, which weakens the limiting effect of La–Cl bond as far as possible. Meanwhile,La 0.75 Al 0.25 OCl exhibits excellent electrical insulating property due to its wide band gap of 5.87 eV. In addition, La 0.75 Al 0.25 OCl exhibits wide electrochemical window with La and Al metal acted as anode materials, respectively (1.92–9.66 V for La and 0–7.74 V for Al). At this stage, La 0.75 Al 0.25 OCl solid electrolyte requires no chlorine-ion uptake and loss in the process of oxidation and reduction, indicating its excellent electrochemical stability. [ABSTRACT FROM AUTHOR]

Cryptosporidium and Giardia are infectious parasitic forms widely distributed in aquatic ecosystems and resistant to disinfection of drinking water. Their presence was investigated in the lower areas of the city's four rivers through a four-stage methodology. Between December 2017 and April 2018, three monitoring campaigns were conducted, with results ranging between not detected to 500 oocysts/L for Cryptosporidium, and between not detected and 300 for Giardia. Cryptosporidium was more abundant, especially in the Machángara River. In the same period, the bacteriological quality of the rivers was also reviewed using Total Streptococci and Fecal Enterococci expressed in colony-forming units (CFU)/100 mL as indicators. The results showed a progressive increase in pollution as the course of the rivers progressed. The sensitivity of bacterial indicators to changes in quality is also observed, which is why their use in specific studies is recommended. It is concluded that untreated domestic wastewater discharges may be the main source of contamination by bacteria and parasites and that there is a relationship between their concentration and the seasonal period. In dry weather, the concentration is higher for both microorganisms. This study fills a gap in knowledge in the region, due to the absence of data on parasitic indicators with great impacts on public health. [ABSTRACT FROM AUTHOR]

The disinfection of treated water is an important process to provide healthy water to the public. The chosen disinfection methods can vary depending on the water source, regulations, targeted microorganisms, operating conditions, capital costs and operation and maintenance costs. Another important factor for decision-makers is the environmental impacts caused by the disinfection process. This paper will reveal the life cycle assessment (LCA) of four different water disinfection scenarios at a municipal scale from the operational phase. A comparison is made between chlorination systems, two ultraviolet disinfection systems that use different types of lamps and an ozonation system. The results demonstrate that the UV disinfection system with low-pressure lamps had the lowest environmental impact across all categories, followed by chlorination. In contrast, the ozonation system and the UV disinfection system with LED lamps showed the highest impacts in all categories, primarily due to their high electricity consumption. Changes in the electricity mix had a substantial influence on the impact categories for all disinfection methods, but the gradation of the water disinfection methods was not that significant. Studies on the environmental impacts of the water disinfection process need to be carried out for larger flow rates to increase the information on this topic. [ABSTRACT FROM AUTHOR]

Ozone generation is a water disinfection method, superior to chlorine in terms of fewer byproducts and no residual taste. However, its high production cost limits its widespread adoption. This paper designs an ozone generation sinusoidal power supply for water treatment. Ozone generation requires a high-frequency and high-voltage power supply to produce ozone from oxygen molecules. The study evaluates two power supply topologies, one with a parallel LC filter and the other with an LCL filter, assessing their feasibility, effectiveness, and reliability. Theoretically, the LCL filter achieves higher gains than the parallel LC filter. The larger inductance in the parallel LC filter reduces gain, while the larger inductance in the LCL filter increases gain. Simulation and practical results validate these findings, achieving gains of 40 for the parallel LC filter and 150 for the LCL filter. [ABSTRACT FROM AUTHOR]

[Display omitted] Pathogen contamination in drinking water sources causes waterborne infectious diseases, seriously threatening human health. Nowadays, stimuli-responsive self-propelled nanomotors are appealing therapeutic agents for antibacterial therapy in vivo. However, achieving water disinfection using these nanobots is still a great challenge. Herein, we report on prebiotic galactooligosaccharide-based nanomotors for sunlight-regulated water disinfection. The nanomotors can utilize galactooligosaccharide-based N -nitrosamines as sunlight-responsive fuels for the spontaneous production of antibacterial nitric oxide. Such a solar-to-chemical energy conversion would power the nanomotors for self-diffusiophoresis, which could promote the diffusion of the nanomotors in water and their penetration in the biofilm, significantly enhancing the inhibition and elimination of the pathogens and their biofilms in aquatic environments. After water treatments, the prebiotic-based residual disinfectants can be selectively utilized by beneficial bacteria to effectively relieve safety risks to the environment and human health. The low-energy-cost, green and potent antibacterial nanobots show promising potential in water disinfection. [ABSTRACT FROM AUTHOR]

This study focuses on the application of activated carbon obtained from cocoa shells for wastewater treatment. The methodology covered the preparation of activated car-bon through collection, drying, carbonization, and chemical activation, followed by the characterization of the wastewater, its treatment through filtration, adsorption, and the final evaluation of the quality of the treated water. Trihalomethanes (THM), metabi-sulfite, and residual free chlorine were determined in the treated water before and after using activated charcoal. The results indicate a 31.2% reduction in THM levels with considerable decreases in metabisulfite and residual free chlorine concentrations. These findings suggest that cocoa shell-activated carbon is effective in removing common contaminants and more specialized compounds. The study highlights the importance of using sustainable materials in wastewater treatment, promoting more efficient and environmentally responsible practices. [ABSTRACT FROM AUTHOR]

Wastewater monitoring provides essential information about water quality and the degree of contamination. Monitoring these waters helps identify and manage risks to public health, prevent the spread of disease, and protect the environment. Standardizing the appropriate and most accurate methods for the isolation and identification of viruses in wastewater is necessary. This review aims to present the major classes of viruses in wastewater, as well as the methods of concentration, isolation, and identification of viruses in wastewater to assess public health risks and implement corrective measures to prevent and control viral infections. Last but not least, we propose to evaluate the current strategies in wastewater treatment as well as new alternative methods of water disinfection. [ABSTRACT FROM AUTHOR]

Introduction: Salinity of water and soil resources is one of the most basic agricultural problems, especially in arid and semi-arid regions. Identifying and domesticating salinity-resistant plant (halophytes) species with economic value is an important strategy for these regions. Materials and methods: This research aimed to investigate the amount of elements and the quality of fodder in several Salicornia species under the influence of water salinity in a factorial experiment with a completely randomized design in pot culture conditions in Bojnourd (North Khorasan province) in 2018. Irrigation treatment was applied at two levels (brackish water and normal water), and Salicornia species treatment included four species (Salicornia persica, S. sinus persica, S. europaea, and S. bigelovii) and Salicornia var Markazi. The source of salty water was the Kal-Shoor river in Esfrain and the source of normal water was the well located in Research and Education of Agriculture and Natural Resurces Center in Bojnourd. Due to the high salinity of Kal-Shoor river, normal water was used to adjust the salinity to the treatment limit of 45 dSm-1. To produce seedlings, Salicornia seeds were planted in plastic combs for seedling production in April 2018. After 60 days, seedlings (10-15 cm) were transferred to pots. The irrigation circuit varied in different growth stages according to weather conditions, and irrigation was done by the weight method with the 80% moisture index of the pots. Results and discussion: The results showed that the amount of nitrogen, phosphorus, potassium, magnesium, sodium and chlorine increased with the increase in irrigation water salinity in all species. The highest accumulations of sodium (11%) and chlorine (23.5%) were observed in S. sinus persica and the lowest amount of sodium (8.6%) and chlorine (21%) were observed in S. persica. Among the Salicornia species, the lowest amount of elements is related to potassium and phosphorus ions, which is mostly due to the limitation of the absorption of these elements under the influence of sodium ions, and as mentioned in the sources, the process of absorption of these elements increases gradually with the growth stages. Maintaining a more negative potential of the membrane is an important factor for salinity tolerance, considering that in saline soils, chlorine and sodium are the most common solutes, the absorption of sodium and chlorine ions is important for regulating osmotic pressure and cytoplasmic concentration. In this experiment, in both irrigation treatments, the most elements in all species were related to chlorine and sodium ions. Based on the measurement of quality variables of fodder, the percentages of protein, crude fat, and ash in salty water treatment were higher than those in normal water. The highest percentage of crude fat (1.32%) in S. var. Markazi was affected by saltwater treatment, which was significantly different from the other species. The highest percentages of protein in S. bigelovii and S. europaea under the influence of saltwater treatment were 6.06% and 6.31%, respectively, which were significantly different from the other species. The highest amounts of ash belonged to S. europaea (63%) and S. bigelovii (62%) in saltwater treatment, and S. sinus persica contained the least ash (49%) in normal water treatment. Although the increase in protein increases the quality of fodder, the increase in the amount of ash and crude fat causes limitations in animal nutrition and digestibility. Therefore, the increase of water salinity has a negative effect on the quality of fodder. Conclusion: Brackish water treatment increased the amount of ash in all species to different proportions, which is a limiting factor for the pure consumption of salicornia in animal feed. Therefore, the relative reduction of water salinity and the selection of suitable species are effective in increasing the quality of fodder.On the other hand, the great ability of Salicornia species to absorb and store salts in their aerial parts provides the basis for the exploitation of their vegetative organs for the production of vegetable salt. Moreover, it is economically important along with other applications of Salicornia (production of fodder, oil, medicines, and protection). [ABSTRACT FROM AUTHOR]

Abstract Increasing climate‐related extreme weather events and conflicts hinder safe water sanitation for vulnerable populations. In developing areas, centralized water systems are impractical due to high costs and poor infrastructure. Thus, technologies utilizing renewable energy like solar and mechanical energy for water treatment hold promise. It is critical to develop photocatalysts and piezoelectric/triboelectric catalysts that capture solar energy as well as mechanical energy to generate disinfectants to maximize energy utilization. The latest advancements in principles, materials, and processes utilizing solar and mechanical energy for water disinfection are highlighted in this review. First, we elucidate both direct and indirect mechanisms of sunlight‐mediated water disinfection, discuss the evolution of photocatalysts from simple UV absorption to visible‐light utilization, and even near‐infrared light exploitation to enhance solar spectrum utilization efficiency. Furthermore, we delve into the fundamental principles of piezoelectricity and triboelectricity relying on mechanical energy conversion as well as summarize the development of piezo/triboelectric catalysts from being driven by high‐frequency energy to utilizing low‐frequency mechanical energy from the environment. Finally, challenges and directions for efficient systems are outlined to inspire rational design strategies and accelerate the production of superior catalytic systems applicable across a broad range.

N -doped carbon nanosheets were synthesized to reveal wide-spectrum photocatalytic H 2 O 2 generation. After the loading of Fe ions, they reveal the enhanced water disinfection ability via photocatalytic cascade. [Display omitted] The pervasive presence of pathogenic bacteria in water environment poses a serious threat to public health. Here, a photocatalytic cascade was developed to reveal great water disinfection. Firstly, N -doped carbon nanosheets (N -CNSs) about 30–50 nm in size were synthesized by a hydrothermal strategy. It revealed wide-spectrum photocatalysis for H 2 O 2 generation via a typical two-step single-electron process. A Fenton agent (Fe ion) was loaded, N -CNSs-Fe can in-situ convert photocatalytic H 2 O 2 into ·OH with high oxidation potential. Moreover, its Fenton active is three times greater than pure Fe2+ owing to electron enrichment from N -CNSs to Fe for Fe3+/Fe2+ cycle. Further investigation displayed that Fe loading also could decrease bad gap and promote charge separation to boost photocatalysis. In addition, N -CNSs-Fe possesses positive surface potential to exhibit strong interaction with negative bacteria, facilitating the capture. Therefore, the nanocomposite can effectively inactivate E. coli with a lethality rate of 99.7 % under stimulated sunlight irradiation. In addition, it also was employed to treat a complex lake water sample, revealing great antibacterial (95.1 %) and dye-decolored (92.3 %) efficiency at the same time. With novel biocompatibility and antibacterial ability, N -CNSs-Fe possessed great potential for water disinfection. [ABSTRACT FROM AUTHOR]

Although, different plant species were utilized for the fabrication of polymorphic, hexagonal, spherical, and nanoflower ZnO NPs with various diameters, few studies succeeded in synthesizing small diameter ZnO nanorods from plant extract at ambient temperature. This work sought to pioneer the ZnO NPs fabrication from the aqueous extract of a Mediterranean salt marsh plant species Limoniastrum monopetalum (L.) Boiss. and assess the role of temperature in the fabrication process. Various techniques have been used to evaluate the quality and physicochemical characteristics of ZnO NPs. Ultraviolet–visible spectroscopy (UV–VIS) was used as the primary test for formation confirmation. TEM analysis confirmed the formation of two different shapes of ZnO NPs, nano-rods and near hexagonal NPs at varying reaction temperatures. The nano-rods were about 25.3 and 297.9 nm in diameter and in length, respectively while hexagonal NPs were about 29.3 nm. The UV–VIS absorption spectra of the two forms of ZnO NPs produced were 370 and 365 nm for nano-rods and hexagonal NPs, respectively. FT-IR analysis showed Zn–O stretching at 642 cm−1 and XRD confirmed the crystalline structure of the produced ZnO NPs. Thermogravimetric analysis; TGA was also used to confirm the thermal stability of ZnO NPs. The anti-tumor activities of the two prepared ZnO NPs forms were investigated by the MTT assay, which revealed an effective dose-dependent cytotoxic effect on A-431 cell lines. Both forms displayed considerable antioxidant potential, particularly the rod-shaped ZnO NPs, with an IC50 of 148.43 µg mL−1. The rod-shaped ZnO NPs were superior candidates for destroying skin cancer, with IC50 of 93.88 ± 1 µg mL−1 ZnO NPs. Thus, rod-shaped ZnO NPs are promising, highly biocompatible candidate for biological and biomedical applications. Furthermore, both shapes of phyto-synthesized NPs demonstrated effective antimicrobial activity against various pathogens. The outcomes highlight the potential of phyto-synthesized ZnO NPs as an eco-friendly alternative for water and wastewater disinfection. [ABSTRACT FROM AUTHOR]

Objective: Evaluate the effects of five disinfection methods on bacterial concentrations in hospital sink drains, focusing on three opportunistic pathogens (OPs): Serratia marcescens, Pseudomonas aeruginosa and Stenotrophomonas maltophilia. Design: Over two years, three sampling campaigns were conducted in a neonatal intensive care unit (NICU). Samples from 19 sink drains were taken at three time points: before, during, and after disinfection. Bacterial concentration was measured using culture-based and flow cytometry methods. High-throughput short sequence typing was performed to identify the three OPs and assess S. marcescens persistence after disinfection at the genotypic level. Setting: This study was conducted in a pediatric hospitals NICU in Montréal, Canada, which is divided in an intensive and intermediate care side, with individual rooms equipped with a sink. Interventions: Five treatments were compared: self-disinfecting drains, chlorine disinfection, boiling water disinfection, hot tap water flushing, and steam disinfection. Results: This study highlights significant differences in the effectiveness of disinfection methods. Chlorine treatment proved ineffective in reducing bacterial concentration, including the three OPs. In contrast, all other drain interventions resulted in an immediate reduction in culturable bacteria (4–8 log) and intact cells (2–3 log). Thermal methods, particularly boiling water and steam treatments, exhibited superior effectiveness in reducing bacterial loads, including OPs. However, in drains with well-established bacterial biofilms, clonal strains of S. marcescens recolonized the drains after heat treatments. Conclusions: Our study supports thermal disinfection (>80°C) for pathogen reduction in drains but highlights the need for additional trials and the implementation of specific measures to limit biofilm formation. [ABSTRACT FROM AUTHOR]

We characterized concentrations of trihalomethanes (THMs), a measure of disinfection byproducts (DBPs), in tap water samples collected from households with utility-supplied water in two rural counties in Appalachian Virginia, and assessed associations with pH, free chlorine, and metal ions which can impact THM formation. Free chlorine concentrations in all samples (n = 27 homes) complied with EPA drinking water guidelines, though 7% (n = 2) of first draw samples and 11% (n = 3) of 5-min flushed-tap water samples exceeded the US Safe Drinking Water Act (SDWA) maximum contaminant level (MCL) for THM (80 ppb). Regression analyses showed that free chlorine and pH were positively associated with the formation of THM levels above SDWA MCLs (OR = 1.04, p = 0.97 and OR = 1.74, p = 0.79, respectively), while temperature was negatively associated (OR = 0.78, p = 0.38). Of the eight utilities serving study households, samples from water served by three different utilities exceeded the EPA MCL for THM. Overall, these findings do not indicate substantial exposures to DBPs for rural households with utility- supplied water in this region of southwest Virginia. However, given the observed variability in THM concentrations between and across utilities, and established adverse health impacts associated with chronic and acute DBP exposure, more research on DBPs in rural Central Appalachia is warranted. [ABSTRACT FROM AUTHOR]

Carpet cleaning guidelines currently do not include the use of an antimicrobial, except after a bodily fluid event. To address this gap, we compared the efficacy of three antimicrobials--two hydrogen peroxide-based (H2O2) products (A and B) and one chlorine-based product (C)--and a steam treatment against two norovirus surrogates, specifically feline calicivirus (FCV) and Tulane virus (TuV). These tests were performed on nylon carpets with either water-permeable or waterproof backing types. The effect of repeated antimicrobial use on carpet properties was also evaluated. For a carpet with water-permeable backing, products A, B, and C achieved a 0.8, 3.1, and 0.9 log10 PFU/coupon reduction of FCV and 0.3, 2.5, and 0.4 log10 TCID50/coupon reduction of TuV, respectively, following a 30 min contact time. For carpet with waterproof backing, only product B achieved a 5.0 log10 PFU/coupon reduction of FCV and >3.0 log10 TCID50/coupon reduction of TuV, whereas products A and C achieved a 2.4 and 1.6 log10 PFU/coupon reduction of FCV and a 1.2 and 1.2 log10 TCID50/coupon reduction of TuV, respectively. Steam treatment achieved a = 5.2 log10 PFU/coupon reduction of FCV and a > 3.2 log10 TCID50/coupon reduction of TuV in 15 seconds on the carpet with both backing types. The repeated use of products A and B decreased the tensile strength of the carpet backing, while use of product B resulted in cracks on carpet fibers. Overall, steam treatment for 15 seconds was efficacious on both carpet types, but only product B achieved efficacy after a 30-minute exposure on the carpet with waterproof backing. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a common pathogen associated with recreational water facilities and poses risks to public health. However, data on the prevalence of P. aeruginosa in tourist destinations like the Canary Islands, Spain, remain limited. We assessed P. aeruginosa prevalence in 23 tourist facilities from 2016 to 2019. Compliance with water quality standards was evaluated, and 3962 samples were collected and analyzed. We examined different types of recreational water installations, including outer swimming pools, whirlpools, and cold wells. Of the sampled facilities, 31.2% did not comply with the current legislation's parametric values, mainly due to inadequate disinfectant levels, water temperature, and P. aeruginosa presence. The prevalence of P. aeruginosa was 4.8%, comparable to some European countries but lower than others. Cold wells displayed the highest non-compliance rate (89.2%) and yet exhibited a lower P. aeruginosa prevalence (1.9%) than outer swimming pools and whirlpools. Children's presence did not significantly impact P. aeruginosa contamination. Chlorine-based disinfectants are more effective than bromine-based ones in controlling P. aeruginosa. Regional variability in contamination was observed, with Fuerteventura showing lower colonization rates. Disinfectant levels play a critical role in P. aeruginosa control, and maintaining adequate levels is essential, particularly in bromine-treated installations. Our findings provide valuable insights into the prevalence and distribution of P. aeruginosa in recreational waters within tourist facilities. Tailored strategies are needed to ensure water safety in different Spanish regions. Continued monitoring and assessment, combined with artificial intelligence and machine learning, will enable the implementation of targeted interventions to protect the health of recreational water users. [ABSTRACT FROM AUTHOR]

Designing materials capable of disinfecting water without releasing harmful by-products is an ongoing challenge. Here, we report a novel polycationic sponge material synthesized from chitosan derivatives and cellulose fibers, exhibiting antibacterial properties. The design of such material is based on three key principles. First, the formation of a highly porous structure through cryogelation for an extensive surface area. Second, the incorporation of cationic quaternary ammonium moieties onto chitosan to enhance bacterial adsorption and antibacterial activity. Lastly, the reinforcement of mechanical properties through integration of cellulose fibers. The presented sponge materials exhibit up to a 4-log (99.99%) reduction within 6 h against both gram-positive B. subtilis and gram-negative E. coli. Notably, QCHI90/Cell, with the highest surface charge, exhibits a 2–4.5 log reduction within 1 h of incubation time. The eco-friendly synthesis from water and readily available biomaterials, along with cost-effectiveness and simplicity, underscores its versatility and feasibility of upscaling. Together with its outstanding antibacterial activity, this macroporous biomaterial emerges as a promising candidate for water disinfection applications. [ABSTRACT FROM AUTHOR]

Bromhexine and ambroxol are among the mucolytic drugs most widely used to treat acute and chronic respiratory diseases. Entering the municipal wastewater and undergoing transformations during disinfection with active chlorine, these compounds can produce nitrogen- and bromine-containing disinfection by-products (DBPs) that are dangerous for aquatic ecosystems. In the present study, primary and deep degradation products of ambroxol and bromhexine obtained in model aquatic chlorination experiments were studied via the combination of high-performance liquid and gas chromatography with high-resolution mass spectrometry. It was shown that at the initial stages, the reactions of cyclization, hydroxylation, chlorination, electrophilic ipso-substitution of bromine atoms with chlorine, and oxidative N-dealkylation occur. Along with known metabolites, a number of novel primary DBPs were tentatively identified based on their elemental compositions and tandem mass spectra. Deep degradation of bromhexine and ambroxol gives twenty-four identified volatile and semi-volatile compounds of six classes, among which trihalomethanes account for more than 50%. The specific class of bromhexine- and ambroxol-related DBPs are bromine-containing haloanilines. Seven of them, including methoxy derivatives, were first discovered in the present study. One more novel class of DBPs associated with bromhexine and ambroxol is represented by halogenated indazoles formed through dealkylation of the primary transformation products containing pyrazoline or tetrahydropyrimidine cycle in their structure. [ABSTRACT FROM AUTHOR]

Water stress and water quality represent major environmental challenges in the 21st century. In response, wastewater management and its potential reuse emerge as strategies to mitigate these problems. This research aims to verify the law of reciprocity in the solar disinfection process of real secondary wastewater effluents for different faecal microorganisms. Flat disinfection reactors, subjected only to natural and continuous UV radiation, were used. The study focused on the optical effect of UV radiation, eliminating the significant influence of the thermal effect and its synergy in solar disinfection at temperatures above 45 °C, by controlling the temperatures of the water samples to levels below 20 °C. Three experimental tests were carried out on sunny days. Each test comprised two trials, under the following conditions: (a) low solar irradiance over a prolonged time (duration approximately: 2.6 h) and (b) high solar irradiance and a shorter period of time (approximately 2 h), with each receiving the same UV dose. Inactivation kinetics was analysed for E. coli, E. faecalis, and C. perfringens (including spores). The results validated the reciprocity law for E. coli in all tests for UV doses > 20 Wh/m2, showing no significant deviations, with inactivation rates of 0.44 to 0.51 m2/Wh for initial concentrations of 106–107 CFU/100 mL. In contrast, for E. faecalis, the reciprocity was only valid at intensities < 700 W/m2, with rates of 0.04 and 0.035 m2/Wh for 105–106 CFU/100 mL; above this irradiance value, the law varied significantly and was not valid. C. perfringens did not show significant disinfection results during the experiments to verify this law, mainly due to the resistance of its spores. Additional experimentation with C. perfringens is necessary, by extending the length of the experiments and/or conducting them at higher irradiance values, in order to reach bacterial inactivation to enable the analysis of the reciprocity law. In general, the main conclusion from these results is that the reciprocity law in solar disinfection would be difficult to use for the estimation of water solar disinfection based on the irradiance and exposure times, as there are deviations from it at least in one specie (E. faecalis). Mores studies should be carried out to fully understand and determine the validity of this law and its potential application for forecasting solar water disinfection. [ABSTRACT FROM AUTHOR]

In this article, the methods of cleaning and disinfection of drinking water in livestock farms are discussed. In order to choose the appropriate cleaning method, first an analysis is made of the water that will be used for irrigation and then the necessary processing is selected - filters, water softening, reverse osmosis, additional mineralization, disinfection by means of UV sterilizers. On the basis of the cost rate for irrigation of dairy cows, the necessary cleaning agents with the most effective capacity are indicated. By observing certain water parameters, the health and quality of life of animals in small and large farms is guaranteed. [ABSTRACT FROM AUTHOR]

Industrial chlorinated solvents continue to be among the most significant issues in groundwater (GW) pollution worldwide. This study assesses the effectiveness of eight novel oxidation treatments, including persulfate (PS), ferrous sulfate, sulfidated nano-zero valent iron (S-nZVI), and potassium ferrate, along with their combinations, for the potential in situ remediation of GW polluted with chlorinated solvents (1,2-dichloroethylene, trichloroethylene, and tetrachloroethylene). Our bench-scale results reveal that the combined addition of PS and S-nZVI can effectively eliminate trichloroethylene (10 µg/L), achieving removal rates of up to 80% and 92% within 1 h, respectively, when using synthetic GW. In the case of real GW, this combination achieved removal rates of 69, 99, and 92% for cis-1,2-dichloroethylene, trichloroethylene, and tetrachloroethylene, respectively, within 24 h. Therefore, this proposed remediation solution resulted in a significant reduction in the environmental risk quotient, shifting it from a high-risk (1.1) to a low-risk (0.2) scenario. Furthermore, the absence of transformation products, such as vinyl chloride, suggests the suitability of employing this solution for the in situ remediation of GW polluted with chlorinated solvents. [ABSTRACT FROM AUTHOR]

The exploration of novel biomarkers to assess poultry health is of paramount importance, not only to enhance our understanding of the pathogenicity of zoonotic agents but also to evaluate the efficacy of novel treatments as alternatives to antibiotics. The present study aimed to investigate potential gut health biomarkers in broiler chicks challenged by Campylobacter jejuni and subjected to a continuous water disinfection program. A total of 144 one-day-old hatched broiler chicks were randomly allocated to four treatment groups with four replicates each, according to the following experimental design: Group A received untreated drinking water; Group B received drinking water treated with 0.01–0.05% v/v Cid 2000™ (hydrogen peroxide, acetic acid and paracetic acid); Group C was challenged by C. jejuni and received untreated drinking water; and Group D was challenged by C. jejuni and received drinking water treated with 0.01–0.05% v/v Cid 2000™. The use of Cid 2000™ started on day 1 and was applied in intervals until the end of the experiment at 36 days, while the C. jejuni challenge was applied on day 18. Potential biomarkers were investigated in serum, feces, intestinal tissue, intestinal content, and liver samples of broilers. Statistical analysis revealed significant increases (p < 0.001) in serum cortisol levels in C. jejuni-challenged broilers. Serum fluorescein isothiocyanate dextran (FITC-d) increased significantly (p = 0.004) in broilers challenged by C. jejuni and treated with drinking water disinfectant, while fecal ovotransferrin concentration also increased significantly (p < 0.001) in broilers that received the drinking water disinfectant alone. The gene expression levels of occludin (p = 0.003) and mucin-2 (p < 0.001) were significantly upregulated in broilers challenged by C. jejuni, while mucin-2 significantly increased in birds that were challenged and received the drinking water disinfectant (p < 0.001). TLR-4 expression levels were significantly (p = 0.013) decreased in both groups that received the drinking water disinfectant, compared to the negative control group. Finally, the C. jejuni challenge significantly increased (p = 0.032) the crypt depth and decreased (p = 0.021) the villus height-to-crypt-depth ratio in the ileum of birds, while the tested disinfectant product increased (p = 0.033) the villus height in the jejunum of birds. Furthermore, the counts of C. jejuni in the ceca of birds (p = 0.01), as well as its translocation rate to the liver of broilers (p = 0.001), were significantly reduced by the addition of the water disinfectant. This research contributes to novel insights into the intricate interplay of water disinfection and/or C. jejuni challenge with potential intestinal biomarkers. In addition, it emphasizes the need for continued research to unveil the underlying mechanisms, expands our understanding of broiler responses to these challenges and identifies breakpoints for further investigations. [ABSTRACT FROM AUTHOR]

Substitution reactions in carbocyanine dyes are used to determine nucleophilic compounds. The interaction of a chlorine-containing carbocyanine dye with a number of medicinal substances is studied. It is shown that, in the reaction with isoniazid in the presence of a surfactant, this dye selectively changes color from yellow-green to violet. The formation of a product of the substitution of chlorine for isoniazid is proven by chromatography–mass spectrometry. The reaction proceeds in 20 min in the presence of 1 mM cetyltrimethylammonium bromide. The limit of detection for isoniazid in water by the photometric method is 10 μg/mL and in diluted artificial urine using fluorimetry, 0.3 μg/mL. The procedure does not use full-spectrum equipment, which simplifies the determination. [ABSTRACT FROM AUTHOR]

In the face of ongoing water pollution challenges, the intricate interplay between dissolved organic matter and disinfectants like chlorine gives rise to potentially harmful disinfection byproducts (DBPs) during water treatment. The exploration of DBP formation originating from amino acids (AA) is a critical focus of global research. Aromatic DBPs, in particular, have garnered considerable attention due to their markedly higher toxicity compared to their aliphatic counterparts. This work seeks to advance the understanding of DBP formation by investigating chlorination disinfection and kinetics using tyrosine (Tyr), phenylalanine (Phe), and tryptophan (Trp) as precursors. Via rigorous experiments, a total of 15 distinct DBPs with accurate molecular structures were successfully identified. The chlorination of all three AAs yielded highly toxic chlorophenylacetonitriles (CPANs), and the disinfectant dosage and pH value of the reaction system potentially influence chlorination kinetics. Notably, Phe exhibited the highest degradation rate compared to Tyr and Trp, at both the CAA:CHOCl ratio of within 1:2 and a wide pH range (6.0 to 9.0). Additionally, a neutral pH environment triggered the maximal reaction rates of the three AAs, while an acidic condition may reduce their reactivity. Overall, this study aims to augment the DBP database and foster a deeper comprehension of the DBP formation and relevant kinetics underlying the chlorination of aromatic AAs. [ABSTRACT FROM AUTHOR]

The aim of this research is to propose a more sustainable swimming pool, in terms of water and energy, in the Costa Brava area. The methodology is focused on the creation of a descriptive water and energy model for swimming pools and their monitoring, to propose the transition to a more sustainable swimming pool, in the context of climate change. The research is characterized by an exploratory, descriptive, and simulation approach to adapt swimming pools to the new requirements. Two significant impacts are highlighted from the perspective of water and energy stress—the carbon footprint, related to environmental impact and climate change, and the new business models of the sector, for a more sustainable tourism, with more sustainable pools. In terms of water balance, evaporation is an important variable and there are technical solutions on the market to control it, such as the use of covers. Furthermore, the modeling and simulation carried out helps to calculate the variable as a tool for improvement. For energy balance, in outdoor pools, pumping is an important variable and there are technologies, such as speed variation, that make it possible to reduce this. Furthermore, it should be noted that this research represents an important tool for the improvement of sustainability and operability for the various stakeholders, especially owners and governments, to face climate change, which is becoming increasingly critical for many regions. [ABSTRACT FROM AUTHOR]

Swimming is a widely practiced exercise in modern society, where there is a heightened interest in health. The exceptional benefits of swimming are well-known, yet the issue of water quality management inevitably arises due to its nature as an aquatic exercise. Several studies reported that chlorine disinfectants commonly used in swimming pool water disinfection could degrade into toxic disinfection by-products (DBPs) and suggested that the DBPs might induce respiratory disorders, including asthma. Conversely, there were also reports that the DBPs had no significant effects on respiratory conditions. In this study, we investigated the influence of swimming exercise and DBPs on asthma. The decomposition products had little effect on the number of T cells in various immune organs. However, swimming exercise was found to increase the cell count in proportion to the exercise duration. Nevertheless, there were no significant changes in other immune cells and the secretion of asthma-related cytokines. These findings indicate that the effects of swimming pool DBPs on respiratory conditions during swimming exercise are either negligible or absent, and instead, the immunological benefits gained through consistent swimming exercise outweigh any potential drawbacks. [ABSTRACT FROM AUTHOR]

Cadmium sulfide (CdS)-based photocatalysts are prepared following a hydrothermal procedure (with CdCl2 and thiourea as precursors). The HydroThermal material annealed (CdS-HTa) is crystalline with a band gap of 2.31 eV. Photoelectrochemical investigation indicates a very reducing photo-potential of −0.9 V, which is very similar to that of commercial CdS. CdS-HTa, albeit having similar reducing properties, is more active than commercial CdS in the reductive dehalogenation of 2,2-dichloropropionic acid (dalapon) to propionic acid. Spectroscopic, electro-, and photoelectrochemical investigation show that photocatalytic properties of CdS are correlated to its electronic structure. The reductive dehalogenation of dalapon has a double significance: on one hand, it represents a demanding reductive process for a photocatalyst, and on the other hand, it has a peculiar interest in water treatment because dalapon can be considered a representative molecule of persistent organic pollutants and is one of the most important disinfection by products, whose removal from the water is the final obstacle to its complete reuse. HPLC-MS investigation points out that complete disappearance of dalapon passes through 2-monochloropropionic acid and leads to propionic acid as the final product. CdS-HTa requires very mild working conditions (room temperature, atmospheric pressure, natural pH), and it is stable and recyclable without significant loss of activity. [ABSTRACT FROM AUTHOR]

As a regulator of alveolo-capillary barrier integrity, Transient Receptor Potential Vanilloid 4 (TRPV4) antagonism represents a promising strategy for reducing pulmonary edema secondary to chemical inhalation. In an experimental model of acute lung injury induced by exposure of anesthetized swine to chlorine gas by mechanical ventilation, the dose-dependent effects of TRPV4 inhibitor GSK2798745 were evaluated. Pulmonary function and oxygenation were measured hourly; airway responsiveness, wet-to-dry lung weight ratios, airway inflammation, and histopathology were assessed 24 h post-exposure. Exposure to 240 parts per million (ppm) chlorine gas for ≥50 min resulted in acute lung injury characterized by sustained changes in the ratio of partial pressure of oxygen in arterial blood to the fraction of inspiratory oxygen concentration (PaO2/FiO2), oxygenation index, peak inspiratory pressure, dynamic lung compliance, and respiratory system resistance over 24 h. Chlorine exposure also heightened airway response to methacholine and increased wet-to-dry lung weight ratios at 24 h. Following 55-min chlorine gas exposure, GSK2798745 marginally improved PaO2/FiO2, but did not impact lung function, airway responsiveness, wet-to-dry lung weight ratios, airway inflammation, or histopathology. In summary, in this swine model of chlorine gas-induced acute lung injury, GSK2798745 did not demonstrate a clinically relevant improvement of key disease endpoints. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 pandemic illustrates the importance of understanding the behavior and control of human pathogenic viruses in the environment. Exposure via water (drinking, bathing, and recreation) is a known route of transmission of viruses to humans, but the literature is relatively void of studies on the persistence of many viruses, especially coronaviruses, in water and their susceptibility to chlorine disinfection. To fill that knowledge gap, we evaluated the persistence and free chlorine disinfection of human coronavirus OC43 (HCoV-OC43) and its surrogates, murine hepatitis virus (MHV) and porcine transmissible gastroenteritis virus (TGEV), in drinking water and laboratory buffer using cell culture methods. The decay rate constants of human coronavirus and its surrogates in water varied, depending on virus and water matrix. In drinking water without disinfectant addition, MHV showed the largest decay rate constant (estimate ± standard error, 2.25 ± 0.09 day-1) followed by HCoV-OC43 (0.99 ± 0.12 day-1) and TGEV (0.65 ± 0.06 day-1), while in phosphate buffer without disinfectant addition, HCoV-OC43 (0.51 ± 0.10 day-1) had a larger decay rate constant than MHV (0.28 ± 0.03 day-1) and TGEV (0.24 ± 0.02 day-1). Upon free chlorine disinfection, the inactivation rates of coronaviruses were independent of free chlorine concentration and were not affected by water matrix, though they still varied between viruses. TGEV showed the highest susceptibility to free chlorine disinfection with the inactivation rate constant of 113.50 ± 7.50 mg-1 min-1 L, followed by MHV (81.33 ± 4.90 mg-1 min-1 L) and HCoV-OC43 (59.42 ± 4.41 mg-1 min-1 L). IMPORTANCE This study addresses an important knowledge gap on enveloped virus persistence and disinfection in water. Results have immediate practical applications for shaping evidence-based water policies, particularly in the development of disinfection strategies for pathogenic virus control. [ABSTRACT FROM AUTHOR]

The introduction of the first list of priority pathogenic fungi by the World Health Organization stresses the need to research and develop public health actions to mitigate infections caused by fungi. One of those actions involves the water disinfection systems, which comprise classical and alternative methods that have been developed in the last decades. Thereby, this work reviews the disinfection of fungi by classical methods such as chlorination, ozonation, and ultraviolet (UV) treatments and alternative advanced oxidation processes (AOPs) such as photo-Fenton, photocatalysis, or couplings of UV with peroxides. The matrices of aquatic systems (sewage, groundwater, drinking water, among others) were considered. A bibliometric analysis is performed initially, and then some aspects of the resistance to antifungals are presented, and the efficiency of the diverse processes in the reduction in fungal loading is also revised. Herein, it is shown the role of the disinfecting agents (e.g., chlorine, hydroxyl radical, or light) and their effects on fungi structures (e.g., direct DNA damage, or indirect damage due to the action of radicals). Moreover, gaps, such as the treatment of antifungal-resistant fungi and limited information about combinations among AOPs, related to the disinfection of water polluted by fungi, were identified. [ABSTRACT FROM AUTHOR]

Alternative water disinfectants to chlorination need to be identified because its effectiveness is limited by water pH and potentially carcinogen by−products resulted from chlorination and organic compound reaction. The first study aimed to evaluate the effect of different drinking water chemical disinfection treatments on water quality, its potential hazard effects on animal health, water and feed consumption, and apparent total tract digestibility in dairy beef bulls fed high-concentrate diets. For 224 days, 24 Holstein bulls (176 ± 16.3 kg BW, and 149 ± 5.8 days of age) were individually assigned to one of four treatments with different drinking water chemical disinfectants: without disinfection (CTR); acidification and chlorination (ACCHL; 0.65 mL/L H3PO4 and 0.14 mL/L NaClO 15%); hydrogen peroxide (PER; 0.15 mL/L); and chlorine dioxide (DIO; 2.50 mL/L). Data were analysed with a mixed-effects model. Treatments affected the chemical characteristics of the water: in ACCHL, pH was 6.60 and free residual chlorine was 0.75 mg/L; in PER, H2O2 was 10.6 mg/L; and in DIO, ClO2 was 0.52 mg/L. Water physicochemical quality parameters in all treatments were below maximal thresholds established for safe water consumption by the Water Safety Royal Decree (RD 140/2003). In addition, the total coliform count of treated waters was reduced (P = 0.01) compared with CTR; moreover, ACCHL and DIO treatments were more effective in reducing total coliform count than PER. Dry matter intake tended (P = 0.07) to increase in DIO compared with CTR. Treatments did not affect blood parameters nor apparent total tract digestibility. The second study aimed to evaluate the potential benefit on animal performance of two drinking water disinfectants under commercial conditions in dairy beef crossbred Holstein bulls fed high-concentrate diets. Ninety-six animals (307 ± 4.4 kg BW, and 224 ± 1.8 days of age) were allocated to six pens for 140 days and assigned to one of two treatments: ACCHL, most common water disinfectant, and DIO. Data were analysed with a mixed-effects model. Water total coliform count and water consumption were similar between treatments. Concentrate intake was greater (P = 0.02) in ACCHL for the last 14 study days. Growth performance and carcass quality were similar between treatments. In summary, acidification and chlorination, H2O2, and ClO2 as drinking water disinfectants in dairy beef bulls had good disinfecting activity without detrimental effects on health and nutrient digestibility, and performance.

Clean and safe water is a fundamental requirement for human survival and well-being. The destruction of civilian infrastructure during wars or natural disasters can severely limit access to clean water for the local population, military, rescue workers and volunteers. The objective of the study was the evaluation of the efficiency of fresh water disinfection by electrolytic ozonation. The ozone concentration was measured photometrically by the intensity of the colour change in the reaction with N, N-diethyl-p-phenylenediamine sulfate. The water quality was assessed microbiologically by determining the total microbial count of the samples and by analysing the colour of the bottom of the flasks in which the water samples were stored. The efficiency of ozonation of artesian water in the field was evaluated. Electrolytic ozonation of 500 mL of spring water for two and five minutes produced an aqueous ozone solution with a concentration of 0.74 and 1.72 mg/L, respectively. Electrolytic ozone decomposed slowly and was detected in the samples three days after the water treatment. Ozonation of spring water for 5 and 10 minutes effectively inactivated all natural microorganisms (2.11 log CFU/mL), the water remained sterile and without any colour changes for a month. Water samples ozonated for 2 minutes did not demonstrate any visible changes after a month of storage, however the natural microflora partially recovered. Planktonic microorganisms in the amount of 2.33 log CFU/mL, as well as biofilms on the walls of the flasks, were detected in a month in the control water samples. The colour of the bottom of the control flasks changed to dirty yellow. In the field, ozonation of water for 10 minutes prevented its spoilage even when the recommended treatment volume was increased by 10 times. The obtained results indicate that electrolytic ozonation is an effective method of freshwater disinfection, and portable ozonators can play an important role in emergency water purification in areas of armed conflicts or natural disasters

Water scarcity and contamination are urgent issues to be addressed. In this context, different materials, techniques, and devices are being developed to mitigate contemporary and forthcoming water constraints. Photocatalysis-based approaches are suitable strategies to address water contamination by degrading contaminants and eliminating microbes. Photoreactors are usually designed to perform photocatalysis in a scalable and standardised way. Few or none have been developed to combine these characteristics with portability, flexibility, and cost effectiveness. This study reports on designing and producing a portable (490 g), low-cost, and multifunctional photoreactor that includes adjustable radiation intensity and two types of wavelengths (UV-A and visible), including combined agitation in a compact mechanism produced through 3D printing technology. The mechanical, electrical, and optical subsystems were designed and assembled into a robust device. It is shown that it is possible to apply radiations that can reach 65 mW/cm2 and 110 mW/cm2 using the installed visible and UV LEDs and apply mechanical agitation up to 200 rpm, all under a ventilated system. Regarding functionality, the photoreactor proof of concept indicated the ability to degrade ~80% and 30% ciprofloxacin under UV and visible irradiation of TiO2 and Ag/TiO2 nanoparticles. The device also showed the ability to eliminate E. coli bacteria, recurring to radiation set-ups and nanoparticles. Therefore, the originally designed and constructed photoreactor concept was characterised and functionally validated as an exciting and flexible device for lab-scaled or outdoor experiments, assuring standardised and comparable results. [ABSTRACT FROM AUTHOR]

Designing efficient antimicrobials for the rapid disinfection of water is increasingly critical owing to the rising threat of pathogenic microorganisms. In this study, direct Z-scheme Bi 2 WO 6 /TiO 2 heterojunctions were constructed using a simple in situ hydrothermal method. The optimal Bi 2 WO 6 /TiO 2 Z-scheme heterojunction inhibited 98.80 % of Escherichia coli (5 × 108 CFU mL−1) at 0.35 mg mL−1 and 99.33 % of Staphylococcus aureus (5 × 108 CFU mL−1) at 0.5 mg mL−1 after 10 min of light-emitting diode (LED) light irradiation. Furthermore, in antibiotic degradation experiments, Bi 2 WO 6 /TiO 2 had a 92.91 % removal rate for ciprofloxacin with a pseudo-second-order degradation rate constant (k) of 0.056 min−1 after 240 min of irradiation. The antibacterial mechanism of Bi 2 WO 6 /TiO 2 was systematically investigated and confirmed to occur by LED light-driven surface activation and efficient charge transfer. The surface and interfacial structures of the Bi 2 WO 6 /TiO 2 samples were studied by high-resolution transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The antibacterial mechanism was studied by controlled experiments and electron spin resonance analyses, which revealed that the primary antibacterial mechanism of Bi 2 WO 6 /TiO 2 is oxidative sterilisation via generated reactive oxygen species. Time-resolved fluorescence spectroscopy was used to analyse the charge-transfer pathway in Bi 2 WO 6 /TiO 2 , which demonstrated that the spatial separation of the redox-active sites extended the lifetimes of the photogenerated carriers, enhancing the oxidative destruction of bacteria. This comprehensive understanding paves the way for the design of new Z-type heterojunction photocatalytic materials for antimicrobial applications. [ABSTRACT FROM AUTHOR]

In food safety implementation, bacterial inactivation is an imperative aspect of hygiene and sanitation. Studies on lithium magnesium silicate (LMS) hydrosol incorporated with slightly acidic electrolyzed water (SAEW) for decontamination of pathogenic bacteria are limited. This present study aimed to investigate the bactericidal efficacy of LMS hydrosol incorporated with SAEW against Escherichia coli. Optimum combination conditions of SAEW, hydrosol concentration, and available chlorine concentration (ACC) were optimized by response surface methodology under the central composite design against the growth of E. coli. The optimum combination conditions of exposure time, hydrosol concentration, and ACC were 9.5 minutes, 1.7%, and 20.5 ppm, respectively. The results showed that the increase in ACC led to inactivation in the survival of E. coli compared with the control (p<0.05). It can be concluded that the best combination percentage between SAEW and hydrosol ranged from 1.5-1.7%, in which E. coli was reduced by 4.50 log10 CFU/mL at an ACC of 9.94 ppm. When increasing the ACC to 14.84 ppm, E. coli was reduced by 4.51 log10 CFU/mL compared with the initial number of bacteria (8.20 log10 CFU/mL) in the control group. The number of bacteria was undetected after increasing ACC to 19.93, 25.15, and 29.88 ppm at 10 min. This study suggests that LMS hydrosol incorporated with SAEW could potentially be used as an effective sanitizer. [ABSTRACT FROM AUTHOR]

In this paper, IEC 61511 was used to evaluate the hazards and risks associated with the continuous operation of the hydrolysis reactor system in the copper-chlorine thermochemical hydrogen production cycle, with a specific focus on the application of automated active safety systems and safety integrated systems. The analysis presented herein was performed using a speculative but representative hydrolysis piping and instrumentation diagram (P&ID) for the hydrolysis reaction, which was based on currently published systems as well as experience with experimental hydrolysis reactors. This analysis was then used to inform the design of a set of automated safety systems that provide the redundant operation of critical devices and can bring the hydrolysis to a safe shutdown state if needed. [ABSTRACT FROM AUTHOR]

The use of integrated plasma-activated water (PAW) with micro/nanobubbles (MNBs), ultraviolet (UV) photolysis, and ultrasonication (US) for the synergistic efficiency of Escherichia coli inactivation in chicken meat was investigated. A 2k factorial design was employed to optimize the combined treatment parameters for pathogen disinfection in Design of Experiments (DOE) techniques. Its effectiveness was evaluated based on electrical conductivity (EC), oxidation–reduction potential (ORP), hydrogen peroxide (H2O2) concentration, and E. coli inactivation. The most significant impact on E. coli reduction was observed for MNBs, UV treatment time, and their interaction (MNBs and UV). Optimal E. coli inactivation (6 log10 CFU/mL reduction) was achieved by combining PAW with MNB and UV for 10 and 20 min, respectively. Integrating PAW with appropriate supplementary technologies enhanced E. coli inactivation by 97% compared to PAW alone. This novel approach provides a promising alternative for pathogen control in chicken meat, potentially improving food safety and shelf life in the poultry industry. [ABSTRACT FROM AUTHOR]

Powdered infant formula (PIF) is prone to Cronobacter sakazakii (C. sakazakii) contamination, which can result in infections that endanger the lives of newborns and infants. Slightly acidic electrolytic water (SAEW) has shown antibacterial effects on a variety of foodborne pathogens and has a wide applicability in the food industry. Here, the antibacterial activity of SAEW against C. sakazakii and its use as a disinfectant on contact surfaces with high infection transmission risk were investigated. The inactivation of SAEW on C. sakazakii was positively correlated to the SAEW concentration and treatment time. The antibacterial effect of SAEW was achieved by decreasing the intracellular adenosine triphosphate (ATP), K+, protein, and DNA contents of C. sakazakii, reducing the intracellular pH (pHin) and destroying the cell morphology, which led to inactivation of C. sakazakii ultimately. To test the applicability of this study, the results showed that approximately 10³ CFU/cm² of C. sakazakii were successfully inactivated on stainless steel and rubber surfaces after a 30 mg/L SAEW treatment for 20 s. These results indicate the antibacterial mechanism and potential application of SAEW against C. sakazakii, as well as a new strategy for the prevention and control of C. sakazakii on stainless steel and rubber surfaces. [ABSTRACT FROM AUTHOR]