Contamination Of Water Resources Research Articles

Assessment of Heavy Metal Contamination in Water Resources of the Andean Mining Zone: A Decadal Analysis of the Santa Rosa River Basin, Ecuador

Assessment of Heavy Metal Contamination in Water Resources of the Andean Mining Zone: A Decadal Analysis of the Santa Rosa River Basin, Ecuador

Recent Methods of Effectively Removing Long-chain and Short-chain Per- and Poly-fluoroalkyl Substances from Drinking Water

As a persistent organic pollutant, the non-biodegradable per- and poly-fluoroalkyl substances (PFAS) pervade an extensive scope of life, leading to widespread contamination of water resources including drinking water. Correlated with multiple diseases, PFAS is highly correlated with dyslipidemia. While the production of long-chain PFAS is banned, many short-chain PFAS become the alternatives. Although most short-chain alternatives show less hazard, some may possess greater harm. As a result, the removal of PFAS from drinking becomes urgent. This paper reviewed the recent methods of adsorptive removal of PFAS by activated carbon, ion exchange resins, and metal-organic frameworks. The main mechanism and innovative modifications of each adsorptive material are summarized, and both long-chain and short-chain PFAS are discussed in each section. This study aims to provide a basic understanding of the current removal approaches of PFAS for scholars. Through literature review, activated carbon and metal-organic framework remain highly effective with evident mechanisms for adsorbing long-chain PAFS, while ion exchange resins show considerable potential in adsorbing short-chain and ultrashort-chain PFAS.

Synthesis of zinc oxide/bismuth oxide nanocomposite photocatalyst for visible light-assisted degradation of synthetic dyes and antibacterial application.

Contamination of water resources by artificial coloring agents and the increasing incidence of bacterial illnesses are two significant environmental and public health issues that are getting worse day by day. Traditional treatment techniques frequently fail to address these problems adequately in a sustainable and environmental friendly way. In response, our study presents a novel photocatalyst that demonstrates superior photodegradation capability and antibacterial qualities in catering the above issues. Sonochemical synthesis route was adopted to synthesize the nanocomposite of zinc oxide/bismuth oxide (ZnO-Bi2O3) along with pure ZnO and Bi2O3. X-ray diffraction investigation was performed to analyze the crystallographic structure and confirmed the formation of the composite. High-resolution transmission electron microscopic analysis showed that the particle size of the composite to be in 20 to 55nm range with the formation of heterojunction at ZnO/Bi2O3 interface. Fourier transformed infrared spectroscopic and micro Raman studies of the nanocomposite sample helped to detect the presence of stretching vibrations linked with Zn and Bi ions. X-ray photoelectron spectroscopy study revealed the chemical constitution and electronic states of the nanocomposite sample displaying the Zn 2p, Bi 4f, and O 1s spectral lines. Investigation on the photocatalytic efficiency of the samples was done and the results showed an appreciable increase in photodegradation efficiency for the composite sample in degrading methylene blue (93.24%) and Congo red (92.47%) dyes in 180min. The effect of pH, photocatalyst amount, and dye concentration on the efficiency of degradation was also been examined. Two primary causes of the enhanced performance of the composite are the generation of hydroxyl radicals (OH•) and the suppression of carrier recombination which is initiated by the synergistic combination of the two metal oxides in the nanocomposite. The nanocomposite sample was found to be stable and reusable for its effective use in environmental cleanup. By using the disk diffusion process, the antibacterial potential of the samples was analyzed and it was discovered that the nanocomposite showed an exceedingly superior antibacterial performance than the pristine samples in preventing the growth of two strains of bacteria, i.e., Escherichia coli and Staphylococcus aureus.

Construction of silver-doped graphitic carbon nitride integrated zeolitic imidazolate framework as an ultra-sensitive probe for colorimetric detection application

Abstract Malachite green, and phloxine B are highly effective antifungal, and antibacterial agents utilized primarily in aquaculture. It is classified within the Triarylmethane dye. Numerous studies have indicated that malachite green, and phloxine B are significantly toxic to both terrestrial and aquatic organisms. More critically, it poses substantial risks to human health and safety. As a result, several governments have prohibited its application in aquaculture and food production. There is a pressing need to develop a novel colorimetric probe for the detection of malachite green, and phloxine B. In response, a composite material was synthesized, combining Zeolitic Imidazolate Framework (ZIF-8) with silver-doped graphitic carbon nitride (Ag-g-C3N4), to serve as a colorimetric probe for the sensitive and selective identification of malachite green, and phloxine B. The Ag-g-C3N4/ZIF-8 composite demonstrated exceptional colorimetric sensing capabilities, attributed to the synergistic interactions between ZIF-8 and Ag-g-C3N4, achieving a detection limit as low as 1.073 nM, and 1.214 nM, for malachite green, and phloxine B, respectively. This composite represents a significant advancement in environmental sensing technology, providing a versatile and effective approach for detecting and addressing contamination in water resources.

Groundwater Quality of the Lower Rio Bravo Aquifer in the Northern Zone of Tamaulipas

Objective: The main objective is to evaluate the quality of groundwater used by the population of the ejidos of Reynosa, Tamaulipas. These wells are used for domestic consumption in rural households and for irrigation of sorghum crops in rainfed agriculture systems. Theoretical Framework: Water supply sources in the northern region of Tamaulipas are experiencing a progressive depletion due to the scarcity of rainfall and the high temperatures characteristic of the region. This challenge is compounded by population growth, which has increased the demand for water. One possible solution to this problem is the exploitation of groundwater resources. However, monitoring activities on the quality of this resource are sporadic, with records dating back to 2006, and in the municipalities of Reynosa and Río Bravo there is almost no culture within the framework of good management practices for sustainable development in the use of groundwater in the lower Río Bravo basin. Method: The approach for the analysis of water quality is carried out in wells located in the northern region of the municipalities of Reynosa and Río Bravo, Tamaulipas, through the linkage with the president of Rural Development District 156 to take samples in wells that are mostly used to supply water to crops and, in some cases, for cleaning activities in farms. Specifically, a detailed physicochemical analysis of the water resource is carried out with the purpose of issuing an opinion on its quality, which will make it possible to determine its potential uses and establish guidelines for sustainable and adequate management in its exploitation. Results and Discussion: In the northern region of the state of Tamaulipas, the use of land for agriculture and the exploitation of the oil industry has been constantly punished. It is a latent fact that agricultural activity represents a significant risk of salinization and groundwater contamination due to the intensive use of agrochemicals. This risk is exacerbated by urban growth, which contributes to water resource contamination through industrial discharges and bacteriological contamination from inadequate wastewater management in population centers. These activities are the main sources of deterioration of groundwater quality and have worsened over time. In addition, the geological context of the region, characterized by stratigraphic formations with natural salinity, further contributes to the complexity of this problem. Research Implications: The results obtained in the development of the project highlight the need for continuous monitoring of economic activities and population growth in the region, to avoid contamination of the aquifer to such levels that for a possible use, specific techniques would have to be implemented that would increase the cost of the water resource, as well as its disposal. Originality/Value: The study of water quality in the aquifer of Río Bravo in the northern region of Mexico represents a considerable challenge, since it is an area affected by problems of insecurity, which makes sampling difficult. However, safe and reliable access to farms and ranches in the area was possible with the cooperation of their owners. This made it possible to carry out adequate sampling and obtain accurate in situ parameters, guaranteeing the veracity of the data obtained.

Saccharomyces cerevisiae inactivation during water disinfection by underwater plasma bubbles: Preferential reactive species production and subcellular mechanisms.

The escalating challenges posed by water resource contamination, especially exacerbated by health concerns associated with microbial fungi threats, necessitate advanced disinfection technologies. Within this context, non-thermal plasma generated within bubble column reactors emerges as a promising antifungal strategy. The effects of direct plasma bubbles within different discharge modes and thus-produced plasma activated water (PAW) on the inactivation of Saccharomyces cerevisiae are investigated. Results show that plasma bubbles generated by dielectric barrier discharge (DBD) mode can effectively inactivate yeast cells (∼4.44 logs reduction) within 1 min, outperforming the spark discharge (SD). In this case, SD can cause a significant portion of cell necrosis, possibly due to the high electric field at the bubble interface. In PAW, DBD and SD produce different dominant long-lived oxygen and nitrogen species, while the crucial short-lived species in yeast apoptosis are both attributed to the singlet oxygen (1O2) as confirmed by scavenger tests. The detection of intracellular reactive oxygen species and antioxidant enzymes further illustrates the role of PAW in triggering apoptosis. Overall, this study demonstrates the discharge mode-dependent modulation of reactive species chemistry in plasma-liquid interactions and provides new insights into the subcellular mechanism of plasma-enabled yeast inactivation for water resource decontamination.

Dibutyl phthalate degradation and toxicity assessment based on hydroxyl radicals generated by plasma jet

Phthalate esters such as dibutyl phthalate (DBP) are widely used as plasticizers in various industries and are known to cause water pollution reaching 15.7 mgL-1 in freshwater and 0.01 mgL-1 in seawater. This study investigated the effectiveness of DBP degradation using an atmospheric-pressure plasma jet (APPJ). Variation in the argon (Ar) gas flow rate influenced the spatial distribution of the hydroxyl radicals (∙OH) as it altered the laminar-to-turbulent flow transition. The highest density of ∙OH was recorded to be 3.1 × 1016 cm−3 when the Ar flow rate was maintained at 2 standard liters per minute. Additionally, the ∙OH concentration in plasma-activated water substantially increased to 35.5 μM with prolonged treatment. Similarly, the concentrations of H2O2, which is formed as a result of the recombination of the ∙OH, gradually increased to 34.4 μM over 8 min of treatment time, and subsequently reduced to 32.6 μM after an additional 2 min of treatment. A degradation rate of 96.6 % was achieved within 10 min of treatment, as confirmed by a gas chromatography (GC)-flame ionization detector. GC-mass spectrometry was used to identify the intermediate products, and propose possible degradation pathways. However, a decline in the energy efficiency was observed because of reduced initial concentration over the extended treatment time. Furthermore, a 40 % increase in cell viability and a 45 % decrease in the percentage of the dead cell population were observed during the exposure of MRC5, astrocytes, and PC-3 cell lines to APPJ-treated DBP solution, indicating reduced toxicity of the contaminant. Thus, the proposed approach can effectively reduce the contamination of water resources by DBP.

Mixtures of toxic organic micropollutants compromise the safety of water resources in urban agglomerations in low- and medium-income countries: The example of Lahore, Pakistan

Contamination of water resources with mixtures of organic micropollutants (OMP) including pesticides, pharmaceuticals, and industrial chemicals is a serious threat to aquatic organisms and human health. Long-term exposure to such pollutants may cause detrimental effects even at very low concentrations. Water resources in urban agglomerations in low- and medium-income countries may be under particular pressure due to high population densities, significant industrial activities, and limited water treatment and management resources. In these areas, many inhabitants directly rely on healthy urban water resources. Using the agglomeration of Lahore, Pakistan, as a case, we studied the occurrence, spatial distribution, and toxic risks of OMP mixtures in different urban water resources using target screening with liquid chromatography high-resolution mass spectrometry. In total, 266 of 576 target analytes were detected in at least one of the 200 samples taken from groundwater, canals, River Ravi and drains within the urban agglomeration. Notably, very high concentrations ranging from 10 to over 100 μg L−1 were found for highly toxic pesticides including several fungicides such as picoxystrobin, the transformation product phthalamic acid, and imazalil, the insecticide etofenprox but also industrial chemicals stemming for example from traffic such as 2-naphthalene sulfonic acid. Our study revealed high toxic risks particularly for invertebrates, fish and algae, with etofenprox as a dominant risk driver. This compound is extensively used in Lahore to control insect vectors of malaria and dengue fever in the urban agglomeration. Mixture risks were assessed using a toxic unit (TU) approach based on organism group specific effect concentrations, complemented with a risk quotient (RQ) approach using the lowest predicted no effect concentrations (PNECs). Acute and chronic risk thresholds were frequently exceeded, often by many orders of magnitude. These very high mixture risks strongly exceed those with previous studies in Europe, Africa and South America.

Nickel Nanoclusters Embedded in Carbon Flaky Frameworks for Electrochemical Ammonia Oxidation

Nitrogenous compounds, such as NH4 +/NH3 and NO3 -, are significant contaminants in water resources. An excess of NH3 leads to eutrophication which poses a threat to aquatic organisms. Electrochemical oxidation has emerged as a promising water treatment technology, offering advantages such as simplicity, small-scale operation, and minimal reliance on additional chemicals. In this study, a nickel-based metal-organic framework (Ni-MOF) was synthesized using 2-aminoterephthalic acid (BDC-NH2) and nickel nitrate. The Ni-MOF was further carbonized to produce nickel oxide and nitrogen-enriched carbon composite, NiOx@NC. Ni ions recrystallized as core-shell nickel oxide/nickel within the 2D mesoporous carbon texture, which served as active sites for ammonia oxidation. Results of characterization showed that the Ni-MOF exhibited a hexagonal and flaky nanoparticle morphology. With increasing pyrolysis temperature, the electrochemical surface area of NiOx@NC significantly increased as to improve the rate of ammonia oxidation. The primary mediator of Ni(OH)2⇌NiOOH phase transition occurred at +1.2 V, compared to oxygen evolution at +1.6 V (vs. Hg/HgO), thereby enhancing the Faradaic efficiency. Batch electrolysis was conducted under parameters, including pyrolysis temperatures, pH, current density, initial concentration, and electrode potential. Among these, NiOx@NC(700), treated at 700 °C, was the best electrode for decomposing ammonium nitrogen of 50 mg-N/L to below 1 ppm within 4 hours at 3 mA/cm2 and pH 10. Oxygenated species, such as nitrate and nitrite, negligibly formed, with N2 nitrogen selectivity surpassing 90% in a paired electrochemical cell assisted with a Cu/Ni cathode. Figure 1

Impact of Natural Organic Matter (NOM) on Nitrate Adsorption in the Membrane Capacitive Deionization (MCDI) Process

Fertilizers containing nitrates significantly boost agricultural productivity, resulting in their extensive application in many regions. However, the majority of nitrate found in water originates from these fertilizers, leading to a gradual increase in nitrate concentration. Nitrogen-catalyzed eutrophication of surface waters leads to algal blooms, resulting in deterioration of water resources. Overexposure to nitrate has adverse effects on plants, the health of animals and humans. The contamination of water resources due to nitrates is becoming a serious issue. Thus, addressing the necessity of nitrate removal becomes important in safeguarding both environmental sustainability and public health. A variety of water treatment technologies for nitrate removal have been developed. Recently, membrane Capacitive Deionization (MCDI) is widely utilized for nitrate removal due to its high ion adsorption capability and selectivity. Meanwhile, there has been insufficient investigation regarding the effect of natural organic matters (NOM) found in natural water resources, which is expected to significantly degrade the salt adsorption capacity of MCDI. Moreover, the mechanism of NO3− adsorption in the presence of NOM in the electrosorption process has not yet been shown clearly. Therefore, more research efforts are needed to investigate the effect of NOM and its significance on MCDI to effectively remove nitrate during operation. In this study, we investigated the influence of NOM on the adsorption of nitrate in the MCDI process. Feed water with and without NOM was analyzed to examine changes in the performance of nitrate adsorption. This study will introduce a decrease in nitrate adsorption rates in water containing NOM due to the formation of complexes facilitated by organic matter.

Metagenomics insights into bacterial diversity and antibiotic resistome of the sewage in the city of Belém, Pará, Brazil.

The advancement of antimicrobial resistance is a significant public health issue today. With the spread of resistant bacterial strains in water resources, especially in urban sewage, metagenomic studies enable the investigation of the microbial composition and resistance genes present in these locations. This study characterized the bacterial community and antibiotic resistance genes in a sewage system that receives effluents from various sources through metagenomics. One liter of surface water was collected at four points of a sewage channel, and after filtration, the total DNA was extracted and then sequenced on an NGS platform (Illumina® NextSeq). The sequenced data were trimmed, and the microbiome was predicted using the Kraken software, while the resistome was analyzed on the CARD webserver. All ecological and statistical analyses were performed using the. RStudio tool. The complete metagenome results showed a community with high diversity at the beginning and more restricted diversity at the end of the sampling, with a predominance of the phyla Bacteroidetes, Actinobacteria, Firmicutes, and Proteobacteria. Most species were considered pathogenic, with an emphasis on those belonging to the Enterobacteriaceae family. It was possible to identify bacterial groups of different threat levels to human health according to a report by the U.S. Centers for Disease Control and Prevention. The resistome analysis predominantly revealed genes that confer resistance to multiple drugs, followed by aminoglycosides and macrolides, with efflux pumps and drug inactivation being the most prevalent resistance mechanisms. This work was pioneering in characterizing resistance in a sanitary environment in the Amazon region and reinforces that sanitation measures for urban sewage are necessary to prevent the advancement of antibiotic resistance and the contamination of water resources, as evidenced by the process of eutrophication.

Nano-fertilizers: The future of nutrient approaches for cereals

Nanotechnology offers a promising solution to address the nutrient demands of cereals, which are nutrient-intensive crops typically reliant on large amounts of inorganic fertilizers. These large quantities of nutrients are supplied to the crop by applying a huge amount of inorganic fertilizer as a soil application led to a decline in environmental systems, particularly affecting the soil health, lesser use efficiency of fertilizers and water resources contamination. In this context, nanotechnology serves as a potential solution. The huge demand for nutrients in cereal crops is met by nano-fertilizers. The nano-fertilizers are now playing a promising role in fulfilling the nutrient requirement of the crops by replacing the normal conventional fertilizers not only for cereals but also for other agricultural crops. The mechanism of action of nano-fertilizers is that they are smaller than the pore size of plant cell walls, allowing them to easily enter and reach the plasma membrane. Nano-fertilizers have 100 times greater surface area than conventional fertilizers, allowing them to easily interact with plant surfaces and increase the absorption of nutrients. Therefore, the nutrient-use efficiency of the crop is increased and shown a positive effect on the physiological and growth parameters of cereal crops, resulting in enhanced yield and improved drought tolerance. This review discussed, the effects and efficiency of nano-fertilizers on cereal crop growth and the correlation between physiological, qualitative, quantitative traits with nano-form of application in detailed manner. This review concludes that nano-fertilizers are the potential nutrient source for cereal crops like rice (Oryza sativa L.), wheat (Triticum aestivum L.), maize (Zea mays) etc. and they are going to be a promising resource for nutrient management in agricultural crops.

New insights into the remediation of chromium-contaminated industrial electroplating wastewater by an innovative nano-modified biochar derived from spent mushroom substrate: Mechanisms, batch study, stability and application

To enhance the adsorption and detoxification capabilities of hexavalent chromium (Cr(VI)) using agricultural spent mushroom substrate (SMS), this study pioneered the preparation of biochar (NBC) from Lentinus edodes spent substrate. Subsequently, nano iron sulfide (FeS) particles were integrated onto NBC with carboxymethyl cellulose (CMC) as a stabilizer, resulting in a novel composite biosorption material, nFeS-BC. The adsorption and reduction potential of both NBC and nFeS-BC against Cr(VI) were evaluated through batch experiments, which identified pH as a critical factor influencing adsorption efficiency. Remarkably, nFeS-BC exhibited a superior maximum adsorption capacity (qmax) of 99.57 mg g−1 and a reduction efficiency of 68.65%, outperforming NBC by 277.73% and 211.76% under optimized conditions, respectively. Characterization techniques including Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX), Fourier Transform Infrared Spectroscopy (FT-IR), and X-ray Photoelectron Spectroscopy (XPS) elucidated the removal mechanisms, predominantly attributed to ion exchange, electrostatic attraction, functional group interaction, and redox reaction. The carbon-oxygen functional groups and nano particles were crucial in the adsorption and reduction processes. Compared with NBC, the incorporation of FeS particles increased the specific surface area and pore volume of nFeS-BC by 130.86% and 183.77%, respectively. nFeS-BC owned a shelf-life of up to ∼3 months of use and exhibited excellent performance in the processing of actual electroplating wastewater with q of 16.71 mg g−1 under 0.1 g L−1 dosage. These findings underscore the potential of nFeS-BC as an efficient material for Cr(VI) removal, presenting a novel adsorbent for the sustainable detoxification of contaminated water resources and the potential for using agricultural waste materials in environmental remediation.

A Systematic Review on Fluoride Contamination in Water Resources of Iran from 2016 to 2023: Spatial Distribution and Probabilistic Risk Assessment (Monte Carlo Simulation).

Because of significant variations and existence of high fluoride (F-) in some waters, Iran has been considered for various fluoride studies in recent decades. Nevertheless, there is a no updated review on fluoride levels especially including F- risk assessment. Thus, this systematic review is mainly aimed to evaluate the spatial distribution of F- content in water sources of Iran using geographic information system (GIS) and conduct the health risk assessment. Besides, the Monte-Carlo Simulation technique with 10,000 iterations was applied for determination of the non-carcinogenic effects of F- in different exposed groups (infant, children, teenagers, and adults). The results indicated that the maximum and minimum concentrations of F- content were related to Jazmourian (Roudbar plain) (4.8mg/L) and Sahneh (0.1mg/L) provinces, respectively, and F- content of more than ≅ 19% of the samples exceeds the Iranian standard value (1.5mg/L). The results showed that the HQ of F- in all groups were higher than 1 with the order of children > infants > teenager > adults in which children were the vulnerable group to F- consumption in study area. Therefore, it is necessary to monitor and continuously measure water supplies for fluoride content and control measures, including removal steps, be taken for human risk reduction.

Utilizing Iron Oxidizing Bacteria (IOB) in the Bio-remediation of Subsurface Drinking Water from Haridwar, Uttarakhand, India

Background and Aim: Iron-oxidizing bacteria (IOB) are harmless, chemotrophic organisms that use oxygen to dissolve iron in wastewater contaminated with heavy metals. They thrive in water with iron concentrations as low as 0.1 mg/L, offering a cost-effective, eco-friendly solution for water treatment. In Uttarakhand, widespread iron contamination continues to limit access to safe drinking water despite efforts to address the issue. This study aimed to explore the use of bioremediation and microbial consortia to reduce and eliminate iron contamination in drinking water sources. Methods: The study employed a biosorption process, where the iron-oxidizing bacteria and microbial consortia were immobilized on a solid carrier (coarser sand) to facilitate contact with the contaminated water. The bacteria and consortia adsorbed iron ions from the water onto the surface of the carrier material through various mechanisms, including ion exchange, chelation, and surface complexation. The biosorption experiments were conducted in a batch mode, where the contaminated water was mixed with the carrier material containing the microbial consortium. The mixture was agitated under controlled conditions to promote iron removal. Results: The study assessed the iron removal efficiency of various carriers (gravel, sand, coarse sand, bentonite, and lignite) and iron-oxidizing bacteria (IOB-1 to IOB-6) from 100 water samples collected in Uttarakhand. The key findings are: Carrier Performance: Coarse sand consistently demonstrated the highest iron removal efficiency among all carriers, with an average removal rate of 84.67% ± 0.02%. Microbial Isolate Performance: Among the IOB strains, IOB-1 exhibited the best iron removal efficiency, achieving an average of 46.67% ± 0.08%. Microbial Consortium: The microbial consortium formed using IOB-1 in combination with coarse sand achieved the highest overall iron removal efficiency of 89.33% ± 0.05. These results underscore the effectiveness of bioremediation techniques, particularly using microbial consortia, for addressing iron contamination in water resources. Discussion: The present study demonstrates the efficacy of bioremediation techniques, specifically utilizing iron-oxidizing bacteria and microbial consortia, in addressing iron contamination in water resources. The results indicate that the selected carriers, particularly coarse sand, and the microbial isolate IOB-1 exhibited significant potential for iron removal. Conclusion: The combination of iron-oxidizing bacteria and suitable carriers offers a promising approach for water treatment in regions affected by iron pollution. The microbial consortia entrapped in coarse sand demonstrated superior performance compared to individual strains, suggesting the synergistic effects of microbial interactions.

Development of free flowing granular hybrid functionalized clay sorbent filters for chromium removal from waste water

Chromium (VI) contamination in water resources at industrial sites poses significant environmental and health risks. Conventional sorbents often suffer from limitations such as clogging, back pressure, poor kinetics, and challenges in coupling with flow systems and regeneration. This study focuses on developing, characterizing, and applying free-flowing granular (FFG) amidoxime-functionalized montmorillonite (Mt) clay sorbents (AO-Mt-H-C) to enhance chromium (VI) removal from contaminated waste water. Batch adsorption experiments demonstrated that AO-Mt-H-C outperformed montmorillonite clay modified with quaternary ammonium alone (Mt-H-C), achieving a Cr (VI) removal efficiency of 50.6 mg g−1 compared to 44.3 mg g−1, due to the synergistic interactions of quaternary ammonium and amidoxime functionalities. To address the limitations of conventional sorbents, such as clogging and poor kinetics, an FFG filter column was developed and tested, showing effective Cr (VI) removal across various water sources with minimal interference in drinking and groundwater. In industrial wastewater with higher matrix loads, over 99 % removal efficiency was achieved with a 25 % increase in sorbent dosage. Desorption and reusability assessments confirmed the AO-Mt-H-C's effectiveness across three cycles. Mathematical modelling using Thomas and Yoon–Nelson equations supported the design of customized treatment systems. Scalability was demonstrated by treating 1.6 m3 of textile industrial effluents (100 mg L−1 Cr (VI)) with quantitative removal efficiency (>99.5 %). This study illustrates that the hybrid functionalization and free-flowing granulation of clay sorbent materials significantly enhance Cr (VI) removal, providing valuable insights for advanced water pollution mitigation and environmental sustainability.

Polysulfone (Psf) Mixed Matrix Membrane incorporating Titanium Dioxide (TiO2)/Polyethylene Glycol (PEG) for the removal of copper

The global increasing contamination of water resources with toxic metals such as copper (Cu), poses severe threats to human health and aqueous ecosystems. Therefore, the ultrafiltration mixed matrix membranes (UF MMMs) possess an applicable approach for the removal of copper ions. This novel fabricated technology can be applied in various wastewater treatment systems for the removal of heavy metals, especially copper. MMMs were fabricated by blending polysulfone (Psf) with additives into the dope solution via the phase inversion method by incorporating titanium dioxide (TiO2) and polyethylene glycol (PEG) in Psf MMMs. Seven Psf MMMs samples labelled M0 to M6, each with its own formulation, were prepared and tested for density, porosity, and degree of Cu retention. MMMs were further characterized via Fourier transform infrared spectroscopy (FTIR), which revealed the range of the IR spectrum of Psf polymer membrane from 1319 cm-1 to 1600 cm-1, 1650 cm-1 to 3400 cm-1 for PEG, and 800 cm-1 to 3600 cm-1 for TiO2 NPs. As for the scanning electron microscopy (SEM), M6 (Psf/TiO2/PEG 6000) was found to be the most dense and highest porous morphology asymmetric Psf MMM. The retained percentage of Cu and flux for M6 attained the highest value of 80.3% and 136.99 L/m2 .h respectively, whereas for the neat Psf membrane, M0 exhibited the lowest retained percentage of Cu and flux, about 25.8% and 61.64 L/m2.h. The inclusion of pore former and additives has shown an improvement of 54.5% in the copper rejection. Moreover, M6 displayed the highest antifouling properties compared to other Psf MMMSs. This study proves that PEG and TiO2 additives have significant potential to improve membrane performance due to the highest percentage of Cu retained on the surface of the membrane as adsorptive separation on Psf MMMs.

Kinetic study of the simultaneous removal of ibuprofen, carbamazepine, sulfamethoxazole, and diclofenac from water using biochar and activated carbon adsorption, and TiO2 photocatalysis

The growing number of pharmaceuticals released into the environment poses a threat not only to the aquatic environment but also to human health. This work introduces a novel approach for the simultaneous analysis of four pharmaceuticals—ibuprofen, carbamazepine, sulfamethoxazole, and diclofenac—each with distinct chemical structures. The study explores the kinetic behavior of these compounds during their removal from water, employing biochar and activated carbon as adsorbents, as well as titanium dioxide (TiO2) for photocatalytic degradation. This utilizes two distinct approaches incorporating adsorption mechanisms. The concentrations of pharmaceuticals were simultaneously measured using High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD). In addition to adsorption, photocatalysis with varying dosages of TiO2 was investigated as an alternative method for pharmaceutical removal. The HPLC- DAD analysis enabled the simultaneous monitoring of all four pharmaceuticals in a single analysis. The Langmuir-Hinshelwood model was applied to the photocatalysis data to assess reaction kinetics. The results demonstrate the efficacy of both adsorption methods in removing pharmaceutical contaminants from water. Integrating both adsorption and photocatalysis experiments in one manuscript allows for a comprehensive evaluation of these methods' individual strengths in water treatment applications, providing insights into their combined potential for addressing pharmaceutical contamination in water resources. The calculated removal efficiencies, Langmuir-Hinshelwood kinetics, half-life values, and equilibrium adsorption capacities provide a comprehensive understanding of the efficiency and mechanisms involved in the removal processes, emphasizing the importance of addressing pharmaceutical contamination in water treatment strategies.

Determination of Tetracycline Group Antibiotics Residues in the Tigris River and Agricultural Lands Fed by Tigris River and Reduction of Unconscious Use of Antibiotics

The recent increase in environmental pollutants is contaminating important natural resources and causing irreversible damage. Due to the limitations of traditional treatment techniques, studies on the problem of micro pollutant contamination of water resources have increased significantly. Antibiotics used in medicine and veterinary medicine cause significant pollution of water resources as residues of these contaminants remain unchanged in the aqueous environment. This has recently been recognised as a global environmental health threat. The ecosystem is vulnerable to residues of these contaminants from agriculture and aquaculture. In this study, the presence of tetracycline group antibiotics, the most commonly used in veterinary medicine, was determined in the Tigris river. This is the first study to date in which antibiotics from the tetracycline group have been identified in the Tigris river. Water samples were taken from 16 different points (80 samples) along the river. Sampling points were grouped as abattoirs, livestock markets, farmland, cafes and bridges near settlements. The samples were analysed for the presence of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC). With a concentration range of 0.037 to 1.756 ng/L, oxytetracycline was found in 14 of the 16 sites. A concentration of 0.004–0.014 ng/L of tetracycline was found in five samples. Chlortetracycline was found in six samples, with concentrations ranging from 0.015 to 0.097 ng/L. According to the study, the tetracycline family of antibiotics was found in the water samples, and oxytetracycline was present in the highest concentrations in most of them.

Antimicrobial studies of visible light-responsive nanoflower spheres Bi2WO6/ZnO

The contamination of water resources in recent years has resulted in the dissemination of harmful bacteria via water sources, posing a significant threat to the safety and well-being of humans, animals, and plants. Consequently, there is a growing concern over the health and sanitation of water resources. Photocatalysis, a novel and very effective antibacterial method, has gained significant attention in the area of antibacterial research. Bismuth nitrate pentahydrate and sodium tungstate dihydrate were used in a straightforward hydrothermal process to create nanoflower spheres Bi2WO6/ZnO photocatalytic composites in molar ratios of 1:1, 1:2, 1:3, and 1:4. The first-ever demonstration of the photocatalytic broad-spectrum antibacterial activity of porous nanoflower spheres Bi2WO6/ZnO composites was shown. The samples were analyzed using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and ultraviolet–visible spectroscopy (UV–vis). The antibacterial activity was evaluated using the dilution coated plate technique, with LED light irradiation. The findings indicate that the Bi2WO6/ZnO composite has a much superior antibacterial activity against both bacteria and fungus compared to individual Bi2WO6 and ZnO. When exposed to LED lighting with an intensity of 35 W, the Bi2WO6/ZnO nanoparticles in a 1:2 ratio at a concentration of 1000 mg/L demonstrated complete antibacterial effectiveness against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis within 30 min. Similarly, the nanoparticles achieved 100 % antibacterial efficiency against Candida albicans within 90 min. The antibacterial efficacy of 1000 mg/L 1:2 Bi2WO6/ZnO nanoparticles against Escherichia coli and Staphylococcus aureus was found to be 100 % within 5 min under natural lighting conditions. The findings indicate that Bi2WO6/ZnO nanoparticles have excellent photocatalytic broad-spectrum antibacterial efficacy.