Search

This article examines the utilization and advancements of constructed wetlands (CWs) in South Asia (SA), focusing on their roles, costs, and efficacy enhancements through pre- and post-treatment units for various pollutants. Notable findings include Phragmites and Canna species as commonly used macrophytes, achieving high removal rates for various pollutants. CWs consistently remove total suspended solids, biochemical oxygen demand, chemical oxygen demand, emerging contaminants, and antimicrobial resistant bacteria at substantial rates. Anaerobic baffled reactors are effective pretreatment devices for high-strength wastewater. Moreover, CWs exhibit lower operational and maintenance costs compared to conventional treatment methods. However, the bibliometric analysis reveals limited regional cooperation in SA. Key challenges identified include the absence of guidelines for media, vegetation, and maintenance. The review underscores the necessity for further research in optimizing CWs' efficiency through land area management, plant selection, and enhanced design and operation and maintenance protocols. [ABSTRACT FROM AUTHOR]

Amid escalating global challenges such as population growth, pollution, and climate change, access to safe and clean water has emerged as a critical issue. It is estimated that there are 4 billion cases of water-related diseases worldwide that cause 3.4 million deaths every year. This underscores the urgent need for efficient water quality monitoring and assessment. Traditional assessment techniques include laboratory-based methods that are manual, costly, time-consuming, and risky. Although some studies leveraged Internet of Things (IoT)-based systems to examine water quality, they only relied on a limited number of water quality parameters (and thus do not offer a comprehensive and accurate water quality assessment), mainly due to the technical difficulties to integrate multiple sensors to a single device. In fact, due to the issues of multimodality, heterogeneity, and complexity of data, the interoperability among sensors with various measurements, sampling rates, and technical requirements makes it very challenging to seamlessly integrate multiple sensors into one device. This study overcame these technical challenges by leveraging multisensor data fusion capabilities to develop an intelligent cloud-based IoT multimodal edge sensing device to provide an automated, real-time, and comprehensive assessment process of water quality. First, a total of nine water quality parameters were identified and considered. Second, the sensing device was designed and developed using an ESP32 embedded system, which is a low-cost, low-power system on a chip (SoC) microcontroller integrated with Wi-Fi and dual-mode Bluetooth connectivity by fusing data from six different sensors that measure the nine identified water parameters on the edge. Third, the overall water quality was evaluated using the National Sanitation Foundation Water Quality Index (NSFWQI). Fourth, a cloud-based server was created to publish the data instantly, and a graphical user interface (GUI) was developed to provide easy-to-understand real-time visualization and information of the water quality. The real-world applicability and practicality of the developed IoT-enabled sensing device was tested and verified in a pilot project (i.e., a case study) of a building located in Newark, New Jersey, for a duration of 6 months. This paper adds to the body of knowledge by being the first research developing a single IoT-enabled device that is capable of reporting NSFWQI in real-time based on 9 water quality indicators encompassing both physical [temperature, total dissolved solids (TDS), turbidity, and pH] and chemical [potassium, phosphorus, nitrogen, dissolved oxygen (DO), and 5-day biochemical oxygen demand (BOD5)] parameters. Thus, this study serves as a multifaceted improvement across different dimensions, fostering healthier, more efficient, and technologically advanced environments. [ABSTRACT FROM AUTHOR]

Pyridinic nitrogen vacancy in carbon nitride for photo-self Fenton-like purification of organic contaminants. [Display omitted] • Carbon nitride with pyridinic nitrogen vacancy was successfully prepared. • Pyridinic nitrogen vacancy promotes charge transfer and activating O 2 into H 2 O 2. • Pyridinic nitrogen vacancy accelerates carbon nitride to adsorb organic contaminants. • Photo-self Fenton-like reaction for photocatalytic degradation of organics. This work reports a carbon nitride with pyridinic nitrogen-vacancy (N 2C V-CN), which purifies organic contaminants via an in-situ photo-self Fenton-like reaction. Experiments and calculations demonstrated that the nitrogen-vacancy induces lone-paired (LP) and symmetry-unpaired electrons, promoting the formation of low-energy LP-π hybridized orbitals and helping to overcome the pairing energy required for oxygen to accept electrons. Furthermore, the nitrogen-vacancy accelerates film and intra-particle diffusion rates of organic contaminants on N 2C V-CN, creating beneficial conditions for reactive oxide species to mineralize organic contaminants. Under sunlight and atmospheric oxygen, a photo-self Fenton-like reaction involving proton-coupled electron transfer occurred on the surface of N 2C V-CN. Furthermore, by integrating photocatalysis with flocculation, about 99.1 % suspended substance, 45.5 % chemical oxygen demand, and 38.4 % biological oxygen demand were reduced from polluted river-water. Constructing N 2C V-CN and understanding its crucial role offer theoretical and methodological insights into the in-situ purification of contaminated water bodies. [ABSTRACT FROM AUTHOR]

Background: Whey, which has high biochemical oxygen demand and chemical oxygen demand, is mass-produced as a major by-product of the dairying industry. Microbial fermentation using whey as the carbon source may convert this potential pollutant into value-added products. This study investigated the potential of using whey powder to produce α-ketoisovalerate, an important platform chemical. Results: Klebsiella oxytoca VKO-9, an efficient L-valine producing strain belonging to Risk Group 1 organism, was selected for the production of α-ketoisovalerate. The leucine dehydrogenase and branched-chain α-keto acid dehydrogenase, which catalyzed the reductive amination and oxidative decarboxylation of α-ketoisovalerate, respectively, were inactivated to enhance the accumulation of α-ketoisovalerate. The production of α-ketoisovalerate was also improved through overexpressing α-acetolactate synthase responsible for pyruvate polymerization and mutant acetohydroxyacid isomeroreductase related to α-acetolactate reduction. The obtained strain K. oxytoca KIV-7 produced 37.3 g/L of α-ketoisovalerate from lactose, the major utilizable carbohydrate in whey. In addition, K. oxytoca KIV-7 also produced α-ketoisovalerate from whey powder with a concentration of 40.7 g/L and a yield of 0.418 g/g. Conclusion: The process introduced in this study enabled efficient α-ketoisovalerate production from low-cost substrate whey powder. Since the key genes for α-ketoisovalerate generation were integrated in genome of K. oxytoca KIV-7 and constitutively expressed, this strain is promising in stable α-ketoisovalerate fermentation and can be used as a chassis strain for α-ketoisovalerate derivatives production. [ABSTRACT FROM AUTHOR]

Background: Whey, which has high biochemical oxygen demand and chemical oxygen demand, is mass-produced as a major by-product of the dairying industry. Microbial fermentation using whey as the carbon source may convert this potential pollutant into value-added products. This study investigated the potential of using whey powder to produce α-ketoisovalerate, an important platform chemical. Results: Klebsiella oxytoca VKO-9, an efficient L-valine producing strain belonging to Risk Group 1 organism, was selected for the production of α-ketoisovalerate. The leucine dehydrogenase and branched-chain α-keto acid dehydrogenase, which catalyzed the reductive amination and oxidative decarboxylation of α-ketoisovalerate, respectively, were inactivated to enhance the accumulation of α-ketoisovalerate. The production of α-ketoisovalerate was also improved through overexpressing α-acetolactate synthase responsible for pyruvate polymerization and mutant acetohydroxyacid isomeroreductase related to α-acetolactate reduction. The obtained strain K. oxytoca KIV-7 produced 37.3 g/L of α-ketoisovalerate from lactose, the major utilizable carbohydrate in whey. In addition, K. oxytoca KIV-7 also produced α-ketoisovalerate from whey powder with a concentration of 40.7 g/L and a yield of 0.418 g/g. Conclusion: The process introduced in this study enabled efficient α-ketoisovalerate production from low-cost substrate whey powder. Since the key genes for α-ketoisovalerate generation were integrated in genome of K. oxytoca KIV-7 and constitutively expressed, this strain is promising in stable α-ketoisovalerate fermentation and can be used as a chassis strain for α-ketoisovalerate derivatives production. [ABSTRACT FROM AUTHOR]

This study investigates the potential of a salt bridge‐mediated microbial fuel cell (MFC) for power generation and wastewater sludge treatment in breweries. Unlike traditional "one‐parameter‐at‐a‐time" methodologies, this study uses a three‐variable Box–Behnken design response surface methodology to optimize critical MFC operational parameters. The effects of parameters such as solution pH, salt bridge molarity, and temperature were studied in the range of 4 to 10, 1 to 5 M, and 20 to 45 g L−1. The optimum operating parameters were found to be solution pH of 5.853, salt bridge molarity of 3.343 M, and temperature of 32.5 °C for chemical oxygen demand and biological oxygen demand removal efficiencies of 92.485 % and 88.51 %, respectively. Temperature was found to be the most significant factor affecting the reactor's performance. [ABSTRACT FROM AUTHOR]

Introduction: With increasing age, patients experience a reduction in immunity and an increase in systemic illnesses. These factors significantly contribute to the occurrence of candidiasis in the oral cavity. New approaches to treating and preventing a wide range of oral disorders may become possible through host immunity modulation. Natural agents are preferred for complete denture wearers to prevent candidiasis, which is one of the leading causes of denture stomatitis. Aim: To assess the efficacy of herbal oral rinses (Triphala) and probiotics against Candida species in denture-wearing patients. Materials and Methods: This randomised double-blinded study clinical study was conducted in the Department of Prosthodontics at MM College of Dental Sciences and Research, Mullana, Ambala, Haryana, India, from August 2022 to January 2023. Ethical clearance was obtained and 60 patients were randomly divided into two groups (n=30): Group-A (Probiotics group) and Group-B (Triphala group). Sample collection was performed at baseline and after an 8-week experimental period. The collected samples were inoculated in Sabouraud Dextrose Agar with Chloramphenicol and incubated for 48 hours at 37°C±2°C in a Biological Oxygen Demand (BOD) incubator. The number of Candida colonies was scored and counted using a Digital Colony Counter, reported as Colony-forming Units (CFU) at baseline and after eight weeks. Data analysis was conducted using the Wilcoxon matched-pair test for comparisons within groups and the Mann-Whitney U-test for pair-wise comparisons (p<0.05). Results: The mean age of patients in Group-A was 61±3 years, while in Group-B it was 60±2 years. The mean CFU for the probiotics group was 44.70±72.5 and for the Triphala group, it was 79.60±58.7 before treatment. After treatment, the mean CFU for the probiotics group was 24.70±271.4 and for the Triphala group, it was 50.67±196.4. Although no significant difference (p-value>0.05) was observed between the two groups, both rinses proved effective against Candida species in denturewearing patients. However, the mean reduction in CFUs was significantly higher for Triphala (p-value=0.021). Conclusion: Both probiotics and Triphala showed a significant reduction in CFU after eight weeks of use. However, Triphala was more effective in reducing Candida compared to probiotics. Therefore, it can be considered an efficient agent for denturewearing patients against Candida species. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is one of the most significant processes for treating fecal sludge. However, a substantial amount of microplastics (MPs) have been identified in septic tanks, and it remains unclear whether they impact the resource treatment of feces. To investigate this, polyethylene terephthalate (PET) was used as an indicator of MPs to study their effect on the anaerobic digestion of fecal sludge (FS). Two digestion systems were developed: FS mono-digestion and FS co-digestion with anaerobic granular sludge. The results indicated that the effects of PET varied between the two systems. PET inhibited volatile fatty acid synthesis in both systems, but the inhibition period differed. During mono-digestion, PET slightly increased gas and methane production, in contrast to the co-digestion system, where PET reduced methane production by 75.18%. Furthermore, in the mono-digestion system, PET increased soluble chemical oxygen demand and ammonia nitrogen concentrations while blocking phosphorus release, whereas the co-digestion system showed the opposite effects. Ultimately, the choice of digestion method is crucial for the resource utilization of septic tank sludge, and the impact of MPs on AD cannot be ignored. [ABSTRACT FROM AUTHOR]

Before 2016, the Eskişehir city landfill was an irregular landfill. Since then, it has been transformed into a regulated landfill. This study aimed to investigate the presence of pollution in the landfill drainage area. For this purpose, water samples were collected from the landfill drainage area and the Kadirbey Farm Spring, upstream of the landfill area, during the rainy and dry seasons of 2021. Analyses of the heavy metal content, total dissolved soil (TDS), chemical oxygen demand, biochemical oxygen demand, pH, phenol material content, ammonia nitrogen content, and conductivity were conducted on the samples. Electrical resistivity tomography (ERT) measurements were also performed along the stream bed. According to Turkish Soil Water Quality regulations, the TDS concentrations of all the samples, except one, were lower than the limits for class 3 water quality. The conductivity limits were within the acceptable range for class 3 water quality. The pH of the water samples was alkaline. The calculated leachate pollution index values indicated a pollution risk. The heavy metal pollution index values for the water samples were under 100. Additionally, 75% of the samples were in the very pure category according to the heavy metal evaluation index, with the remaining samples classified as slightly affected. According to the ERT measurements, soils with low resistivity near the landfill were notably laterally wider. The conductivity decreased with the increasing distance from the landfill site. Low resistivity zones, such as plumes, were disconnected from each other. The shape and volume of highly contaminated plumes decreased toward BH1. Based on the study outcomes, it is recommended to measure the water pollution parameters at periodic intervals within the landfill drainage area. [ABSTRACT FROM AUTHOR]

The present study tries to account for the diversity of desmids and also determine their distribution and abundance in Thattekkad Bird Sanctuary, situated in Ernakulam District, the first Bird Sanctuary in Kerala and lies within the geographical limits of 10°08′N 76°41′E and 10°13′N 76°68′E. The water samples collected were preserved and the physico-chemical parameters were analyzed using standard protocols. The study was carried out over a period of one year, from March 2022 to April 2023 in three seasons (pre-monsoon, monsoon, and post-monsoon) from the freshwater resources within the sanctuary like rivers, streams, and ponds. The following physico-chemical parameters of water were analyzed: the concentration of nitrates and phosphates, pH, temperature, dissolved oxygen (DO), biological oxygen demand (BOD), and turbidity. Desmids are unicellular algae that belong to conjugating green algae and occur exclusively in freshwaters, each cell consists of two almost symmetrical and often profusely sculptured segments. The current study identified a total of seventy-four taxa, which are distributed under four families and 18 genera. Predominant genera included were Cosmarium (21), Euastrum (12), and Staurastrum (8). Notably Heimansia pusilla, Euastrum praemorsum, Euastrum jenneri, Staurastrum saltans var. javanicum, Cosmarium clepsydra var. bicardia are new reports to India, five species are new reports to Kerala and all species being novel to Thattekkad Bird Sanctuary. The Shannon's diversity index is in the range of 0.8070 to 1.0151, and Simpson's Index range between 0.5051 to 0.6177. [ABSTRACT FROM AUTHOR]

The elevated level of pollutants in water highlights the urgency of effective wastewater treatment. Hence, the concern about the potential of microalgae as an economically and environmentally sustainable for wastewater treatment is addressed. Wastewater treatment using microalgae resulted in significant reductions in micropollutants by 82 % for chemical oxygen demand (COD) and biological oxygen demand (BOD). Iron (Fe) concentration was reduced by 99 %, while calcium (Ca) decreased by 25 %. Algal biomass obtained from wastewater is executed for biochar production and bio-stimulant preparation. Bio-stimulant treatment significantly enhanced seed germination and increased shoot and root lengths in maize (Zea mays) and beans (Phaseolus vulgaris) compared to the control. Conversely, seed germination was completely suppressed in both maize and beans in the presence of biochar of bio-stimulant treatment. The GC-MS and NMR analysis study revealed the presence of key compounds in the microalgal extract that have a great contribution to plant growth. Hence, the study concludes the multifaceted and potential application of microalgae as a remediation and bio-stimulant in a sustainable way. [Display omitted] • Integrated wastewater treatment, recycling and reuse technology (SDG 6a). • Utilization of wastewater treated C. sorokiniana for biochar & bio stimulant generation. • Bio-stimulant influenced germination and growth of Zea Maize and Phaseolus vulgaris. • GC-MS analysis identified key compounds in bio-stimulant for plant growth promotion. [ABSTRACT FROM AUTHOR]

In this study, we performed continuous high spatial resolution temperature measurements (six thermistors per 1–1.4 m water column) at six sites in three shallow temperate ponds during the warm season. These measurements were accompanied by experiments on plankton and sediment respiration rates, including the relationship between temperature and sediment respiration. Continuous temperature measurements allowed the construction of detailed stratification profiles, as well as the construction of seasonal trends in both plankton respiration and sediment oxygen demand, all with high temporal resolution (at 1-h intervals). A peak in plankton respiration was detected in mid-summer, while sediment oxygen demand showed two peaks, one before and one after the plankton peak. Sediment respiration made a significant contribution to total respiration in the water column and even exceeded plankton respiration during certain periods. The criteria for determining stratification and its thresholds, which differ for shallow and deep waters, are discussed in detail. We discuss the uncertainties in estimating respiration and explore contributing factors, such as limitation of sediment oxygen demand by low oxygen concentrations near the bottom and sampling time. In addition, we used statistics to analyze the effect of environmental factors on sediment surface oxygen. On the basis of statistical analysis, water column turbidity was found to be the most significant factor, followed by duration of stratification breakdown, dissolved oxygen (DO) in the surface layer, water column depth, chlorophyll a concentration in the water column, time of day, plankton respiration near the pond bottom, duration of stratification, and temperature near the pond bottom. [ABSTRACT FROM AUTHOR]

This study aimed to assess the trophic status of Pegametan Bay, Bali, Indonesia, as influenced by floating net cage aquaculture activities during June 2019 (dry season) and March 2021 (wet season). The trophic status was assessed using 24 parameters developed from a literature review, and water samples were collected from four observation stations. Data were analyzed using field measurements and laboratory analyses. The results showed that dissolved oxygen ranged between 2.6–9.1 mg/l in June 2019 and 3.4–7.7 mg/l during the March 2021 measurement period, salinity (33.6–34.4 ppt and 31–34 ppt), turbidity (0.77–6.33 FNU and 1.2–3.42 FNU), water clarity (4.18–11.92 m and 4.44–8.44 m), Biological Oxygen Demand (10.5–26 mg/l and 1–17 mg/l), Chemical Oxygen Demand (3.68–11 mg/l and 15.5–46.5 mg/l), chlorophyll-a (0.11–0.24 mg/l and 0–0.56 mg/l), Total Dissolved Solids (20,400–22200 mg/l and 21,300–53400 mg/l), ammonia (0.038–0.178 mg/l and 0.01–0.3 mg/l), nitrate (0.02–0.706 mg/l and 0.01–0.03 mg/l), orthophosphate (0.014–0.174 mg/l and 0.04–1.59 mg/l, and culturable bacteria (0–1.74 ∙ 105 CFU/mL and 0–1.61 ∙ 108 CFU/mL). Pegametan Bay exhibited a significant decrease in water quality between June 2019 and March 2021, with mesotrophic and eutrophic trophic states. The parameters determining changes in the trophic state of Pegametan Bay were orthophosphate, TSS, organic content, E. coli, Salmonella, and Vibrio. This trophic state assessment can be used for early detection, monitoring, water quality control, and eutrophication control, thereby ensuring sustainable aquaculture activities and optimal marine resource production. [ABSTRACT FROM AUTHOR]

Food and dairy processing industries consume large quantities of clean water for various processes throughout the plant operations and consequently generate large amounts of wastewater. The objective of this study is to treat the wastewater of food and dairy industries using ZnO nanoparticles (ZnO NPs) to control the pH level and reduce contamination levels. The wastewater from three industries was tested for pH, total dissolved solids (TDS), turbidity, Chemical Oxygen Demand (COD), and Biochemical Oxygen Demand (BOD). The ZnO NPs are prepared with an average size of less than 100 nm by using a simple precipitation method. The obtained particles were characterised by X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) proving the nano size of Zinc Oxide nano particles. The effluents have been treated with the ZnO NPs by varying doses resulting in reducing all contaminants to an acceptable level as recommended by concerned environmental organisations. [ABSTRACT FROM AUTHOR]

Inadequate energy management leads to more emission exposure, which causes climate change, severe environmental contamination, and human health risks. Therefore, the World Health Organisation (WHO) monitors universal efforts to prevent emissions and encourages governments to develop industries to transform the green economy. During the current study, the energy and cost variation was observed through three years (2020, 2021, and 2022) at a surface water plant in southern Egypt. Consistent with applying operation strategies that met convenient standard operating procedures (SOPs) during 2021 and 2022. Energy consumption was reduced by 13% to 17%, and the cost decreased by 5% to 12% for 2021 and 2022, respectively. These energy and financial savings should be considered as an influence of the water safety plans (WSPs). Detrended correspondence analysis (DCA) was utilised to identify the mechanism of energy consumption and its impact on the cost during the study period. The finding proves that the energy and cost rise is related to increased water demand during the summer months, periodic/emergency maintenance, and comprehensive cleaning activities. WSPs were applied to control biological oxygen demand (BOD), chemical oxygen demand (COD), and oil and grease (O & G) that show increasing values than Egyptian law. [ABSTRACT FROM AUTHOR]

Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L. [ABSTRACT FROM AUTHOR]

The Gd-doped ZnO/SnO2 nanocomposites with various atomic percentages (0, 0.5, 0.8, and 1.2 at%) of gadolinium (coded as GdZS0, GdZS1, GdZS2, and GdZS3) was synthesis via the sol–gel method and explored for photodegradation against dye solutions exposing solar light irradiation. The synthesized nanocomposites were characterized employing the XRD, FTIR, FE-SEM, Raman spectroscopy, BET analysis and UV–Vis spectrophotometer. The FE-SEM results indicated that the formation of nanoparticles to nanoflowers covered with Gd ions was observed with an increased doping concentration of Gd. The optical bandgap was evaluated and found in the range of 3.21–3.27 eV for GdZS nanocomposites. The GdZS nano-photocatalysts were investigated against the degradation of different organic dyes and GdZS3 shows the highest degradation efficiencies of 99.3%, 98.3% and 99.4% towards MO, MB and RhB dyes, respectively at neutral pH in aqueous media. Before and after photodegradation. Biological oxygen demand and chemical oxygen demand tests to make estimations of mineralization. The investigations are very promising for the degradation process in rare earth doped metal oxide nanocomposites. A plausible photodegradation mechanism of synthesized nanocomposites under investigation has also been proposed. [ABSTRACT FROM AUTHOR]

The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = − 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = − 0.7112, p = 0.0252) and TDS and bacterial load (r = − 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the effects of the wastewater treatment plant located in the Aziziye District of Erzurum Province on the Karasu River. For this purpose, water samples were taken from 3 stations for a year between 2022-2023. The mean water temperature was measured in situ during sampling as 13.8 ˚C, the mean pH value was 7.7, the mean electrical conductivity was 403 μs/cm, and the mean dissolved oxygen value was 6 mg/l. The mean total suspended solid (TSS) amount was determined as 46.7 mg/l, the mean chemical oxygen demand (COD) concentration was 28.9 mg/l, the mean biological oxygen demand (BOD) concentration was 18.5 mg/l, the mean total nitrogen (TN) concentration was 4.47 mg/l, the mean nitrate (NO3) concentration was 5.35 mg/l, the mean nitrate nitrogen (NO3-N) concentration was 1.21 mg/l, the mean total hardness (TH) was 155 mg/l, the mean ammonium (NH4) concentration was 2.75 mg/l, and the mean ammonium nitrogen (NH4-N) concentration was 2.16 mg/L. As a result, it was determined that the Wastewater Treatment Plant positively affected some water quality parameter values of the Karasu River. [ABSTRACT FROM AUTHOR]

This study aimed to assess the feasibility of employing indigenous cyanide-degrading bacterial strains for the treatment of cassava mill effluent (CME) in Nigeria, a hazardous waste material posing significant public health risks. The physicochemical properties and heavy metal concentrations in CME were determined through standard methodologies. Cyanide-degrading bacteria were isolated, characterized, and identified using molecular techniques. These strains were immobilized within a porous network of cross-linked biochar, confirmed through SEM imaging, and evaluated alongside free cells for CME bioremediation. Multiple variables were examined to assess the effluent's pollution load, including pH, electrical conductivity (EC), chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total dissolved solids (TDS), nitrate (NO3), phosphate (PO4), and cyanide levels, falling within respective ranges of (4.00-4.02), (2394-2618 S/cm), (985-1219 mg/L), (1556-1667 mg/L), (3459-3705 mg/L), (2709-2812 mg/L), (251-311 mg/L), (87.25-118 mg/L), and (25.00-28 mg/L). Copper was the most prevalent heavy metal in the effluent, while chromium was detected at the lowest levels, with mean values of 10.00-12.39 mg/L and 0.00-0.27 mg/L, respectively. The study revealed severe contamination of the effluent, above the Federal Environmental Protection Agency (FEPA) threshold limit. The 16S rDNA of the cyanide degrading bacteria were deposited at the NCBI database and the following GenBank accession numbers were assigned (MK71248O, MK71281, MK712482, and MK712483) for Pseudomonas putida, Bacillus subtilis, Alcaligenes faecalis and Leuconostoc mesenteroides respectively. Results of the bioremediation approach demonstrated a substantial reduction in physicochemical parameters and heavy metal contents, indicating a promising biological treatment strategy to mitigate CME's adverse effects on public health. In conclusion, despite elevated physicochemical parameters and heavy metal concentrations in CME, this study offers a promising avenue for employing biological treatments to mitigate environmental and public health impacts. Further research and application of this technique hold substantial potential for cassava mill effluent management in Nigeria and other regions facing similar challenges. [ABSTRACT FROM AUTHOR]

This research focuses on the impact of pulsed feeding of corn residues on biogas production from pig manure. It also analyzes the properties and microbial diversity in the resulting product. The study highlights the increasing global demand for pork and the resulting environmental challenges, such as effluent management, and suggests that biogas production can be a sustainable solution. The research was conducted at a model farm in Argentina and involved evaluating biogas production and microbial variability at different stages of the pulsed feeding process. The results showed a significant decrease in the chemical and biochemical oxygen demands after the degassing process, indicating a reduction in organic matter. The biogas composition improved with an increase in methane and a reduction in volatile fatty acids. There was also an increase in biogas and methane production and a decrease in methane production lag time, indicating an improvement in anaerobic digestion efficiency. Microbiological analysis revealed a reduction in microbial diversity during pulsed feeding, indicating the adaptation of the microbial community to new conditions. Overall, the study demonstrates the potential of pulsed feeding of corn residues to enhance biogas production from pig manure, with significant implications for effluent management in pork production and sustainable biogas production. [ABSTRACT FROM AUTHOR]

The potential for corrosion and odor emissions from a combined sewer interceptor system in Northwest Chicago was investigated. Seven manholes along the interceptor system were selected as monitoring locations, and eight critical physical-chemical and biological parameters were measured semiweekly at each location for four weeks during the morning and afternoon hours. Statistical analyses were performed to determine the diurnal variability of 5-day biochemical oxygen demand (BOD5), as well as the variability of total sulfide with respect to BOD5 and the sewer flow rates. Subsequently, the Pomeroy–Parkhurst mathematical model was used to predict the change in total sulfide concentration in a mile-long segment of the interceptor system. The model was calibrated by modifying the sulfide flux coefficient in the generation term to reflect the conditions in these interceptors, such that the measured values and model predictions were in agreement. A strong linear relationship between the system's wastewater flow and water quality characteristics and the modified sulfide flux coefficient was found (R2=0.828). With limited wastewater characteristic data, the modified Pomeroy–Parkhurst model can be used in predicting the change in total sulfide concentrations for this interceptor. [ABSTRACT FROM AUTHOR]

The effect of COVID-19 was observed on water quality parameters (WQPs) of river Ganga, and the overall quality of water was analysed with the aid of weighted arithmetic water quality index (WAWQI), which provides a scientific platform for comparison of water quality (WQ) during pre-, during and post-lockdown. The correlation of parameters was also determined to check the spatial variation of parameters among the monitoring stations. Analysis of Variance (ANOVA) was also performed to confirm the impact of lockdown on WQ. In this study, six water quality parameters (Dissolved Oxygen (DO), pH, Biochemical Oxygen Demand (BOD), Electrical Conductivity (EC), Nitrate (NO3), and Total Coliform (TC)) were reviewed at five monitoring stations (Shuklaganj, Jajmau Bridge, Ranighat, Jajmau Pumping Station, and Bithoor) of river Ganga at Kanpur stretch. Results revealed that NO3 was well within the permissible limits at all the stations with respect to all the designated classes specified by CPCB. Lockdown helped in the reduction of BOD concentration from 3.4 to 1.7 mg/l, about 50% maximum, at Shuklaganj from Feb-20 to April-20 and at the same time, the study also revealed that DO concentration was escalated at all the monitoring stations at a significant rate up to 54.86%, highest at Shuklaganj downstream. Water Quality Index (WQI) at Ranighat shows a significant reduction of 30.85% as WQI decreases to 76.28 from 99.81. Similarly, diminution of 59.23% in WQI was seen at Shuklaganj with WQI value declining from 96.27 to 60.46. ANOVA reveals that the lockdown has affected BOD and TC significantly as compared to other parameters. However, there is a noticeable improvement in general characteristics at all sites due to the low levels of tourism and industrial activity during COVID. A correlation analysis was also conducted to deduce the degree of association between the WQPs. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the utilization rate of organic substrates contained in sanitary landfill leachates (SLLs) by fixed and suspended biomass reactors. Five bioreactors were designed, constructed, and tested for chemical oxygen demand (COD) removal. We applied three levels of organic loading in the influent for each bioreactor, including (1) a rotating biological contactor (RBC) (12, 20, and 25 g COD/m2/day); (2) a trickling filter (TF) (2.67, 5.33, and 8 kg COD/m3/day); (3) an upflow anaerobic sludge blanket (UASB) (13.31, 15.98, and 18.65 kg COD/m3/day); (4) an upflow anaerobic filter in two separated stages (UAF-2SS) (3.71, 2.76, and 1.8 kg COD/m3/day); and (5) an upflow anaerobic filter in three separated stages (UAF-3SS) (2.25, 3.45, and 4.44 kg COD/m3/day). Two equations for predicting the substrate utilization rate (SUR) of organic compounds by microorganisms were calibrated and validated, modeled under a nonsteady state condition. We modified Monod's equation to obtain the significant organic SUR and COD removal efficiency by the biomasses. These kinetic parameters were performed by the microorganisms fixing controlled experimental conditions for pH (8–9) and temperature for the UAFs (20°C, 27°C, and 34°C) and the remaining reactors (18°C– 20°C). The SUR and COD removal efficiency results were as follows: for UASB, −400 to −800 mg/L/h , 70% to 85%; for UAF-3SS, −100 to −300 mg/L/h , 85% to 95%; for UAF-2SS, −100 to −200 mg/L/h , 70% to 85%; and for RBC and TF, −50 to −250 mg/L/h , 70% to 80%. The results were mainly influenced by the structural arrangement of the organic compounds being biodegraded and the geometric configurations of the bioreactors in multiple separated stages, allowing the influence of the solubility of the recalcitrant substances, which varied from 7 to 14:1 COD dilition, to obtain subinhibitory levels for the microbial metabolism and achieve a high COD removal efficiency. Practical Applications: Two of the five bioreactors evaluated in this study, the upflow anaerobic filter in two separated stages and the upflow anaerobic filter in three separated stages, are proposed and designed as innovative reactors for treating groundwater from tropical aquifers contaminated with hydrocarbons. Additionally, UAFs were configured in a coupled bioreactor arrangement (i.e., a sequencing batch reactor followed by UAFs) to restore water quality by removing organic compounds in tropical rivers. By comparing the five bioreactors, the capacity for the chemical oxygen demand removal was significant related to the organic substrate utilization rate (SUR) for treating sanitary landfill leachates with low recalcitrance levels (i.e., rapidly biodegradable). Rapidly biodegradable SLLs can be associated with La Cortada-SLL percolated from the cells/trenches excavated for the disposal of municipal solid waste (MSW) (i.e., Pamplona Municipality, Colombia) due to the contents of a high fraction of putrescible wastes (67%) and a high biochemical oxygen demand/chemical oxygen demand ratio (62%). This level ratio produced a suitable SUR obtained from the microbial metabolism starting with the upflow anaerobic sludge blanket reactor (−400 to −1,200 mg/L/h) followed by the remaining bioreactors (−150 to −350 mg/L/h). Upflow anaerobic filters in multiple separated stages reactors constitute a feasible technical option for overcoming medium to high recalcitrance levels in SLLs obtained from cells/trenches excavated storing around 25% components fraction (e.g., metals, plastics, rubber, leather, textiles). [ABSTRACT FROM AUTHOR]

AbstractWater resources are precious resources around the world, but pollution is becoming increasingly severe. While the degree of damage to water caused by organic pollutants is reflected by chemical oxygen demand, which is also an important indicator for hydrological monitoring. Therefore, accurate measurement of chemical oxygen demand is necessary. The rapid development of water quality detection by ultraviolet visible spectrum analysis as an efficient, convenient, and pollution-free new water quality detection method has been achieved. When we were processing ultraviolet visible spectral absorbance data, various environmental factors can affect the chemical oxygen demand light absorption value, thus affecting the accuracy of detection. So there are some goals, such as more comprehensively extracting the feature wavelength and reducing the interference to achieve better detection results. It is expected that the model can be applied to a portable water quality detection device. It is necessary to consider detection time, reduce model training parameters, and improve detection speed. Therefore, this article proposes Competitive Adaptive Weighted Sampling-Convolutional Neural Network-Long Short-Term Memory and Competitive Adaptive Weighted Sampling-Convolutional Long Short-Term Memory models for detecting chemical oxygen demand in water. To verify the effectiveness of the proposed model, the model was trained on the experimental dataset and the detection results of all models involved in the article were compared. It can be confirmed that the application of these two proposed algorithms results in less detection time and higher accuracy in concentration detection. [ABSTRACT FROM AUTHOR]

High-precision tidal forecasting plays a crucial role in providing reliable tidal information to coastal communities, ship operators, fishermen, and government agencies. Existing tidal prediction models, such as backpropagation neural networks (BPNN) and genetic algorithm-optimized BPNN (GA-BPNN), frequently difficulty in in achieving high precision because they rely solely on past tidal variations for real-time predictions. Signal-to-Noise Ratio (SNR) data have emerged as a valuable indicator closely related to real-time sea level changes due to the widespread adoption of Global Navigation Satellite System Interferometric Reflectometry (GNSS-IR) technology. In this paper, we propose a nowcasting tide level prediction method by adding SNR data to BPNN, i.e., Improved BPNN and Improved GA-BPNN, which predicts the next momentary tide level value by using the previous 15 tidal values and real-time SNR as input factors to BPNN. The results of 100-day, 200-day and 1-year tide prediction based on Astoria and Friday Harbor tide gauge stations show that the improved model prediction accuracies are better than the traditional model. Meanwhile, among the two improved models, Improved GA-BPNN has the higher prediction accuracy and can adapt to different time lengths of tide level prediction. [ABSTRACT FROM AUTHOR]

The inverse problem of reconstructing two space-varying coefficients in a system of one-dimensional (1-d) time-dependent advection-diffusion-reaction (ADR) equations is considered. The ADR system can be used as a water quality model which describes the evolution of the biochemical oxygen demand (BOD) and dissolved oxygen (DO) in a river or stream. The coefficients to be reconstructed represents the effect of the deoxygenation and superficial reaeration processes on the DO and BOD concentration in water. Hölder stability estimates for the coefficients of interest are established using the Carleman estimate technique. [ABSTRACT FROM AUTHOR]

Bung Binh Thien Lake, the largest freshwater lake in An Giang, is vital for providing drinking water, supporting agriculture, and sustaining local services. Recently, the lake has been facing organic pollution from household wastewater and local production activities. This study evaluated the water quality using biochemical oxygen demand (BOD5) and dissolved oxygen (DO) parameters, collecting nine water samples from different locations. The DELWAQ model was applied to assess seasonal changes and water quality distribution. During the 2022 rainy season, the average DO value was 5.42 mg/L, meeting the A2 class standard (= 5 mg/L), while the BOD5 value was 12.25 mg/L, within the B1 class standard (= 15 mg/L). In the dry season, the DO value dropped to 4.82 mg/L, and the BOD5 value increased to 12.63 mg/L, indicating higher phytoplankton density and organic pollution. The simulated DO and BOD5 values closely matched observed values, with NSE values of 0.74 and 0.87 for DO and BOD5, respectively, in the flood season, and 0.86 and 0.88 in the dry season. The DELWAQ model proved effective in simulating water quality at Bung Binh Thien Lake, providing valuable data for environmental management and decision-making. This study also serves as a useful reference for further research and water quality management. [ABSTRACT FROM AUTHOR]

This research aims to analyze the efficiency of processing liquid waste from the laundry industry using the Free Water Surface Constructed Wetland (FWS) system with Azolla microphylla plants. The research method used is experimental research by manipulating independent variables and controlling other relevant variables, as well as observing the effect on the dependent variable. Laundry waste samples were taken from Berkah Laundry, Puri Gading, Bekasi. The results showed that the biomass of Azolla microphylla plants increased significantly from day 0 to day 12, with a growth rate between 0.0289 - 0.0477 grams/day and plant density between 185.19 ind/m2 - 277.78 ind/m2. The influent BOD concentration of laundry liquid waste during the acclimatization stage ranged from 5.89 - 10.54 mg/L, while the effluent BOD ranged from 4.35 - 6.98 mg/L, with the highest efficiency reaching 33.8%. The constructed wetland system with Azolla microphylla plants has proven to be effective in reducing pollutant content in liquid waste, with a BOD removal efficiency of 11.1% - 17.7% and COD of 14.5% - 39%. The conclusion of this research is that the use of artificial wetlands with Azolla microphylla plants can be an effective and environmentally friendly alternative solution for processing liquid waste from the laundry industry. The implications of this research show the potential for applying constructed wetland technology in the clothes washing industry to reduce the negative impact of waste on the environment. [ABSTRACT FROM AUTHOR]

Laundry businesses in Indonesia have high economic development opportunities. However, laundry wastewater in Indonesia does not yet have a good environmental culture and regulations for service users. Constructed wetland can be used as a sustainable biological processing technology, uses low energy, and does not require high costs to process laundry wastewater. The aim of this research is to analyze the ability of horizontal sub-surface flow constructed wetlands in a batch system with different numbers of aquatic bamboo plants (Equisetum hyemale) in degrading chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) in laundry wastewater. The research results showed that reactor 2 HSSF CW with a total of 200 E. hyemale plants produced higher removal efficiency compared to reactor 1 HSSF CW with a total of 120 E. hyemale plants where reactor 2 produced COD and BOD5 removal efficiency respectively. amounted to 88.22% and 90.30% while reactor 1 produced COD and BOD5 removal efficiencies of 86.04% and 88.10% respectively. Based on these results, reactor 1 and reactor 2 horizontal sub-surface flow constructed wetlands with E. hyemale plants produced effective performance in reducing COD and BOD5 concentrations in laundry wastewater. [ABSTRACT FROM AUTHOR]

Nutrient enrichment and climate warming threaten freshwater systems. Metabolic theory and the paradox of enrichment predict that both stressors independently can lead to simpler food‐webs having fewer nodes, shorter food‐chains and lower connectance, but cancel each other's effects when simultaneously present. Yet, these theoretical predictions remain untested in complex natural systems. We inferred the food‐web structure of 256 lakes and 373 streams from standardized fish community samplings in France. Contrary to theoretical predictions, we found that warming shortens fish food‐chain length and that this effect was magnified in enriched streams and lakes. Additionally, lakes experiencing enrichment exhibit lower connectance in their fish food‐webs. Our study suggests that warming and enrichment interact to magnify food‐web simplification in nature, raising further concerns about the fate of freshwater systems as climate change effects will dramatically increase in the coming decades. [ABSTRACT FROM AUTHOR]

River water quality often follows a long-memory stochastic process with power-type autocorrelation decay, which can only be reproduced using appropriate mathematical models. The selection of a stochastic process model, particularly its memory structure, is often subject to misspecifications owing to low data quality and quantity. Therefore, environmental risk assessment should account for model misspecification through mathematically rigorous and efficiently implementable approaches; however, such approaches have been still rare. We address this issue by first modeling water quality dynamics through the superposition of an affine diffusion process that is stationary and has a long memory. Second, the worst-case upper deviation of the water quality value from a prescribed threshold value under model misspecifications is evaluated using either the divergence risk or Wasserstein risk measure. The divergence risk measure can consistently deal with the misspecification of the memory structure to the worst-case upper deviation. The Wasserstein risk measure is more flexible but fails in this regard, as it does not directly consider the memory structure information. We theoretically compare both approaches to demonstrate that their assumed uncertainties differed substantially. From the application to the 30-year water quality data of a river in Japan, we categorized the water quality indices to be those with truly long memory (Total nitrogen, NO3-N, NH4-N, and SO 4 2 - ), those with moderate power-type memory (NO2-N, PO4-P, and Total Organic Carbon), and those with almost exponential memory (Total phosphorus and Chemical Oxygen demand). The risk measures are successfully computed numerically considering the seasonal variations of the water quality indices. [ABSTRACT FROM AUTHOR]

Brassware industry constitutes the second most polluting industrial sector in Fez city, Morocco, owing to its high heavy metal load. The aim of this study is to examine and evaluate the performance of vertical flow constructed wetlands in treating brassware effluents using various plant species. Ten treatment systems were planted with four types of plants: Chrysopogon zizanioides, Typha latifolia, Phragmites australis, and Vitex agnus-castus, while another system remained unplanted. These systems underwent evaluation by measuring various parameters, including pH, electrical conductivity, suspended solids, chemical oxygen demand, biological oxygen demand, sulfates, orthophosphates, total Kjeldhal nitrogen, ammonium, nitrates, nitrites, and heavy metals such as silver, copper, and nickel, using standard methods over of ten weeks. The results obtained demonstrate effectiveness of these systems. When planted with Ch. zizanioides, the systems achieved elimination rates of 83.64%, 98.55%, 91.48%, 86.82%, 80.31%, 96.54%, 98%, and 98.82% for suspended solids, ammonium, nitrites, BOD5, sulfates, orthophosphates, silver, and nickel, respectively. System with V. agnus-castus showed significant reductions in nitrate and copper, with rates of 84.48% and 99.10%, respectively. Considerable decrease in pH and electrical conductivity values was observed in all systems, with a notable difference between planted and control systems regarding effectiveness of treatment for other parameters. The novelty of this study lies in the application of constructed wetlands for the treatment of brassware effluents in the city of Fez, Morocco. Consequently, a comparison was conducted to assess the removal efficiency of Chrysopogon zizanioides (L.) Roberty and Vitex agnus-castus L., in comparison to Typha latifolia L. and Phragmites australis (Cav.) Trin. These four plant species were specifically chosen for their high elimination capacity and resistance to the toxicity of the pollutants. Notably, this study represents an unexplored aspect in the existing literature. Nevertheless, T. latifolia and P. australis have been extensively utilized in constructed wetlands for treating diverse wastewaters. The findings from this study can also be extrapolated to pilot-scale constructed wetlands, offering valuable insights for the removal of pollutants from brassware wastewater. [ABSTRACT FROM AUTHOR]

The Kereh River in Penang, Malaysia, has faced severe pollution for over 40 years due to untreated wastewater from swine farms in Kampung Selamat, discharged via stormwater drains. Despite official claims that all 77 swine farms treat their wastewater to meet regulatory standards, local non‐governmental organizations and villagers have challenged this, though their concerns lack scientific backing. This study evaluates the river's water quality by analyzing samples from upstream (US), midstream (MS), and downstream (DS), and from Parit Cina‐Parit Besar, a conduit for untreated swine wastewater. Fourteen parameters were measured against Malaysia's National Water Quality Standards (NWQS). Significant differences were found in six parameters: ammonium nitrogen (AN), biochemical oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO), total suspended solids (TSS), and oil and grease (OG). While Dunn's post hoc pairwise comparison showed no significant differences among river segments, mean values indicated increased pollution downstream, particularly after the convergence with untreated swine wastewater. River classification worsened, with water quality index dropping from 69.88 ± 11.37 score (Class III) US to 38.49 ± 12.74 and 50.44 ± 3.14 scores (Class IV) MS and downstream, respectively. A significant positive correlation between E. coli and AN (r = 0.71, p < 0.01) suggests a common point source pollutant, particularly the untreated swine wastewater. The river exhibits low oxygen levels and high organic matter and nutrient concentrations, especially MS and downstream, highlighting substantial ecological and public health risks. Effective enforcement of waste treatment regulations and enhanced monitoring are crucial for mitigating pollution and restoring the river's ecosystem. Collaboration between authorities and pig farmers is essential to improve water quality and maintain the river's ecological balance. Practitioner points: Severe Kereh River pollution: Untreated swine wastewater from Kampung Selamat pig farms, primarily via Parit Cina‐Parit Besar, has degraded the river for over 40 years.Regulatory non‐compliance: Despite official claims, untreated swine wastewater continues to pollute the river, challenging regulatory standards.Significant pollution indicators: Elevated levels of AN, BOD, COD, DO, TSS, OG, and E. coli signal severe pollution midstream and downstream.Water quality index drop: WQI scores classify midstream and downstream sections as polluted, indicating worsening conditions downstream.Urgent need for action: Enforcing regulations, improving wastewater treatment, and relocating pig farms are crucial for restoring the Kereh River. [ABSTRACT FROM AUTHOR]

This 5-year study (2015 - 2019) investigates the dynamics of phytoplankton and their correlation with environmental factors including water volume, physicochemical and nutrient availability in Mae Kuang Dam, Northern Thailand. The study identified 177 taxa across 6 groups, with Charophyta being predominant (53.3 %) in both wet and dry seasons, specifically in the genus Staurastrum. Taxonomic richness was higher in the wet season, with green algae being the most abundant. In addition, Cyanobacteria, Bacillariophyceae and Chrysophyceae showed increased densities. Annual variations peaked in 2015, decreased in 2017 and exhibited a slight increase thereafter. Cyanobacteria experienced blooms in the wet season, accompanied by significant fluctuations in Charophyta, Cyanophyta, Dinophyta and Euglenophyta. Notably, Cyanophyta exhibited a 20-fold increase from 2015 to 2019. Redundancy Analysis (RDA) highlighted the influence of soluble reactive phosphorus (SRP), conductivity, air temperature, pH, total dissolved solids (TDS) and biochemical oxygen demand (BOD) on phytoplankton during the dry season. Lower water volumes and concentrations of water bodies may intensify the impact of certain factors on phytoplankton communities during this period. In the wet season, pH, conductivity, TDS, ammonia, air temperature and BOD played significant roles, as increased rainfall and nutrient runoff occurred. These results indicate that the combined effects of these environmental variables and hydrological events, including water volume and water static, could influence the dynamics of phytoplankton and water quality. This finding helps us understand the shifts in the aquatic ecosystem under the environmental factors in Thailand. Therefore, further research is needed, emphasizing the necessity for well-planned dam management to maintain both water quality and ecological stability. [ABSTRACT FROM AUTHOR]

Tannery effluents contain high amounts of polluting chemicals, such as salts and heavy metals released often to surface waters. New economic and eco-friendly purification methods are needed. Two adsorbing materials and five salt-tolerant fungal isolates from mangrove habitat were studied. Purification experiments were carried out using the pollutant adsorbents biochar and the biomass of vetiver grass (Chrysopogon zizanioides) roots and the fungi Cladosporium cladosporioides, Phomopsis glabrae, Aspergillus niger, Emericellopsis sp., and Scopulariopsis sp., which were isolated from mangrove sediment. They efficacy to reduce pollutants was studied in different combinations. Salinity, turbidity, total dissolved solids, total suspended solids, phenols, nitrogen, ammonia. Biological and chemical oxygen demand (BOD, COD) and several heavy metals were measured. The adsorbents were efficient reducing the pollutants to 15–50% of the original. The efficiency of the combination of biochar and roots was generally at the same level as the adsorbents alone. Some pollutants such as turbidity, COD and ammonium were reduced slightly more by the combination than the adsorbents alone. From all 14 treatments, Emericellopsis sp. with biochar and roots appeared to be the most efficient reducing pollutants to < 10–30%. BOD and COD were reduced to ca 5% of the original. The treatment was efficient in reducing also heavy metals (As, Cd, Cr, Mn Pb, Zn). The fungal species originating from the environment instead of the strains present in the tannery effluent reduced pollutants remarkably and the adsorbents improved the reduction efficiency. However, the method needs development for effluents with high pollutant concentrations to fulfil the environmental regulations. [ABSTRACT FROM AUTHOR]

Background: The majority of existing industries in Ethiopia discharge untreated effluents into nearby water bodies, streams and open land. The wastewater generated by Gondar malt factory (GMF) was disposed freely and join a natural wetland implemented for the treatment of the wastewater. The objective of the study was to analyze and characterize wastewater from GMF and to evaluate the effectiveness of the wetland for the treatment purpose. Methods: Different Physicochemical quality indicators (color, turbidity pH, temperature, Total Dissolved solids, Total Suspended solids, total solid, conductivity, alkalinity, hardness, nitrate, phosphate, sulfate, free chlorides, heavy metals-(Cd, Cr, Fe, Mn, and Pb)and Biological Oxygen Demand were measured according to the standard procedures. Data was analyzed using Statistical Package for Social Sciences (SPSS-25). Analysis of Variance (ANOVA) was used to find whether significant differences existed in the different sampling stations for the parameters studied. P value less than 0.05 was considered to show significant difference. Results: The results of this study revealed that most of the quality indicators were improved in value after the water passed through the wetland except for alkalinity M, sulfite, Mn, temperature and pH. From ANOVA result, it was noted that there was a significant mean difference between the stations except for chromium, manganese and lead. The result showed that the wetland plays a great role in the removal of pollutants where the best performance was obtained at removal efficiency of 96.188% PO4HR,75.63% Nitrate,>99% Cl2, ammonia and nitrite 99.99%, 92.77% sulfate,84.36% Total hardness,87.43% color, and for others it is ranged between 30 and 60%. Conclusion: the study concluded that GMF wetland was almost effective and had potential in treatment of the wastewater from the discharging facilities (especially for nutrients, alkalinity P, hardness, color and chloride). It is recommended that wetlands should be conserved and used as wastewater treatment facility. [ABSTRACT FROM AUTHOR]

AbstractThe aim of this work is to investigate the influence of an alkaline pretreatment of the Mediterranean plant Carpobrotus edulis on the adsorption capacity toward the dye methylene blue and to estimate the content of soluble organic matter that can be released into the aqueous solution by this biomaterial. The biomaterial used was characterized by SEM-EDX, SS, FT-IR, pHZ, COD and BOD5. Removal of methylene blue (MB) dye by this biomaterial was carried out and the effects of physicochemical factors such as initial pollutant concentration, adsorbent dose, contact time, pH and temperature were investigated. After adsorbent treatment, the soluble organic matter was reduced by 97%, 96%, and 96% for biological oxygen demand, chemical oxygen demand, and organic matter, respectively. Kinetics and equilibrium studies of MB adsorption on the bioadsorbents were fitted with a pseudo-second order kinetic model and a Langmuir model, respectively. The maximum adsorption amount of the modified C. edulis plant was 153.9 mg/g at 298°K. The thermodynamic parameters show that the adsorption process was possible and spontaneous in nature. The adsorption mechanism of MB on the surface of biomaterials was attributed to the electrostatic interaction and H-bonding. The prepared biomaterial (0.016 U$ per gram) was easily regenerated with aqueous HNO3 solution, with a slight decrease in adsorption capacity up to five cycles. The results of Taguchi experimental design and analysis of variance showed that contact time, adsorbent mass and initial concentration are the most important factors affecting the removal efficiency with a contribution of 43.91%, 32.68%, and 22.95%, respectively. The maximum removal capacity of MB dye in optimal operating conditions was 99.39%, which was obtained at the optimum conditions of m = 1 g, pH 4, T = 35 °C, Ci = 1000 mg/L, tc = 5 min. These results confirm previous results obtained with the batch system and show that this absorbent is also promising for the removal of cationic dyes from wastewater. [ABSTRACT FROM AUTHOR]

The increasing global water pollution leads to the need for urgent development of rapid and accurate water quality monitoring methods. Microbial fuel cells (MFCs) have emerged as real-time biosensors for biochemical oxygen demand (BOD), but they grapple with several challenges, including issues related to reproducibility, operational stability, and cost-effectiveness. These challenges are substantially shaped by the selection of an appropriate air-breathing cathode. Previous studies indicated a critical influence of the cathode on both the enduring electrochemical performance of MFCs and the taxonomic diversity at the electroactive anode. However, the effect of different gas diffusion electrodes (GDE) on 3D-printed single-chamber MFCs for BOD biosensing application and its effect on the bioelectroactive anode was not investigated before. Our study focuses on comparing GDE cathode materials to enhance MFC performance for precise and rapid BOD analysis in wastewater. We examined for over 120 days two Pt-coated air-breathing cathodes with distinct carbonaceous gas diffusion layers (GDLs) and catalyst layers (CLs): cost-effective carbon paper (CP) with hand-coated CL and more expensive woven carbon cloth (CC) with CL pre-applied by the supplier. The results show significant differences in electrochemical characteristics and anodic biofilm composition between MFCs with CP and CC GDE cathodes. CP-MFCs exhibited lower sensitivity (16.6 C L mg−1 m−2) and a narrower dynamic range (25 to 600 mg L−1), attributed to biofouling-related degradation of the GDE. In contrast, CC-MFCs demonstrated superior performance with higher sensitivity (37.6 C L mg−1 m−2) and a broader dynamic range (25 to 800 mg L−1). In conclusion, our study underscores the pivotal role of cathode selection in 3D-printed MFC biosensors, influencing anodic biofilm enrichment time and overall BOD assessment performance. We recommend the use of cost-effective CP GDL with hand-coated CL for short-term MFC biosensor applications, while advocating for CC GDL supplied with CL as the preferred choice for long-term sensing implementations with enduring reliability. [ABSTRACT FROM AUTHOR]

Flue gas emissions are the waste gases produced during the combustion of fuel in industrial processes, which are released into the atmosphere. These identical processes also produce a significant amount of wastewater that is released into the environment. The current investigation aims to assess the viability of simultaneously mitigating flue gas emissions and remediating wastewater in a bubble column bioreactor utilizing bacterial consortia. A comparative study was done on different growth media prepared using wastewater. The highest biomass yield of 3.66 g L−1 was achieved with the highest removal efficiencies of 89.80, 77.30, and 80.77% for CO2, SO2, and NO, respectively. The study investigated pH, salinity, dissolved oxygen, and biochemical and chemical oxygen demand to assess their influence on the process. The nutrient balance validated the ability of bacteria to utilize compounds in flue gas and wastewater for biomass production. The Fourier Transform–Infrared Spectrometry (FT–IR) and Gas Chromatography–Mass Spectrometry (GC–MS) analyses detected commercial-use long-chain hydrocarbons, fatty alcohols, carboxylic acids, and esters in the biomass samples. The nuclear magnetic resonance (NMR) metabolomics detected the potential mechanism pathways followed by the bacteria for mitigation. The techno-economic assessment determined a feasible total capital investment of 245.74$ to operate the reactor for 288 h. The bioreactor's practicability was determined by mass transfer and thermodynamics assessment. Therefore, this study introduces a novel approach that utilizes bacteria and a bioreactor to mitigate flue gas and remediate wastewater. [ABSTRACT FROM AUTHOR]

This study explores the optimization of iron electrocoagulation for treating laundry greywater, which accounts for up to 38% of domestic greywater. Characterized by high concentrations of surfactants, detergents, and suspended solids, laundry greywater presents complex challenges for treatment processes, posing significant environmental and health risks. Utilizing response surface methodology (RSM), this research developed a second-order polynomial regression model focused on key operational parameters such as the area-to-volume ratio (A/V), current density, electrolysis time, and settling time. Optimal treatment conditions were identified: an A/V ratio of 30 m2/m3, a current density of 10 mA/cm2, an electrolysis duration of 50 min, and a settlement period of 12 h. Under these conditions, exceptional treatment outcomes were achieved, with turbidity removal reaching 94.26% and COD removal at 99.64%. The model exhibited high effectiveness for turbidity removal, with an R2 value of 94.16%, and moderate effectiveness for COD removal, with an R2 value of 75.90%. The interaction between the A/V ratio and electrolysis time particularly underscored their critical role in electrocoagulation system design. Moreover, these results highlight the potential for optimizing electrocoagulation parameters to adapt to daily fluctuations in greywater production and meet specific household reuse needs, such as toilet flushing. This tailored approach aims to maximize contaminant separation and coagulant efficiency, balance energy use and operational costs, and contribute to sustainable water management. [ABSTRACT FROM AUTHOR]

Objective: The current research aimed to investigate the physicochemical and bacteriological quality status of the Kalte River in Wolaita Sodo Town, southern Ethiopia. Methods: A total of 42 water samples were collected using sterile glass bottles from three different river sites: Damota (upstream), Kera (midstream), and Gututo (downstream). All the water samples were examined for the presence of heterotrophic bacteria, total coliform and fecal coliform using direct plate count method and membrane filtration method. Standard methods suggested by American water works association were used to analysis the physicochemical parameters of the water samples. Results: The results revealed that the total heterotrophic bacteria, total coliform, and fecal coliform count ranged from 8.9 to 12.6 × 104 cfu/ml, 7.5–11.3 × 102 cfu/ml and 5.7–9.7 × 104 cfu/ml, respectively. The bacterial count results indicated that the river water crossed the WHO-recommended limit of potable water. Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella, and Shigella species were the common bacterial pathogens isolated from river water samples. The results of the physicochemical analysis revealed that some of the parameters Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and turbidity exceeded the maximum permissible limits of WHO and other parameters were below the WHO permissible limits. Conclusion: Therefore, the presence of bacterial pathogens, fecal coliform indicators, and some physicochemical parameters of the Kalte River exceeding the recommended limits may expose users of the river water to the risk of infection. [ABSTRACT FROM AUTHOR]

Palm oil Mill effluent Materials (POME) are significantly more contaminated than municipal sewage due to their high chemical and biological oxygen demand (BOD and COD). This study examines the properties of POME wastewater under typical physical settings to track the growth conditions of microalgae, namely Botryococcus sp., in various volumes at varying POME dilutions. Begin with analyzing POME's water quality measurements and conclude the growing conditions of microalgae. Botryococcus sp. microalgae could not flourish in diluted raw POME. However, it was well propagated in diluted anaerobic POME under adequate light and oxygen conditions. The finding shows that diluted anaerobic POME 70% is the ideal dilution for microalgae Botryococcus sp. to proliferate. Raw POME is physically described as a thick, brownish liquid with a high total solids and turbidity concentration that is contained in water. The study explores the use of Botryococcus sp. culture and propagation in POME materials for sustainable bioenergy production, highlighting the potential of microalgae for future economic benefits. [ABSTRACT FROM AUTHOR]

Textile industry wastewater is rich in color, has a low BOD/COD ratio, and contains high levels of salts (TSS and TDS). There is the presence of heavy metals at high concentrations. This has a major environmental impact underlined by chemical oxygen demand (COD) and biochemical oxygen demand (BOD). These issues arise from the presence of dye, pieces of fiber, and other surface treatment agents viz., detergents, salts, and caustic soda. Hence membrane optimization is investigated for treatment and recovery of these components, which would provide both economic and ecological benefits. It was required to provide chemically stable membranes, which would provide efficient separation for these components at effluent conditions of pH, temperature, and other parameters. A major challenge here was a selection of membrane and backing material with sustainability at low pH conditions of textile effluent. Hencepolysulfone (PSF) based membranes with cellulose as backing were optimized and tried for clarification of textile effluent. These membrane properties were further optimized for the recovery of other components. Membrane formation and performance were optimized with the proposition of a two-stage process for clarification and further concentration. Formed membranes showed excellent removal of impurities, validated by ICPMS. The clarified solution can be further treated for concentration enhancement from 7 to 20 %. Such recovered alkaline solution can be recycled or used in further applications. This solution provides an economically attractive and environmentally benign process. Further, it provides the advantages of low energy consumption, high efficiency in separation, and non-thermal processing of sensitive composite products. [ABSTRACT FROM AUTHOR]