Search

The Nile River islands are recognized as the most productive lands in Egypt. Although, these islands are vulnerable to several natural and man-made crises. The present study was aimed to evaluate the consequences of different anthropogenic activities on the heavy metals load and histological alterations in O. niloticus and S. galilaeus collected from four different Nile River islands along the Great Cairo sector (Egypt), and the possible health risks for human consumers. Metals were accumulated in both fish muscles in the following order: Fe > Zn > Cu > Mn > Pb. S. galilaeus was recorded higher metal pollution index than O. niloticus, while El-Warrak Island was documented the highest MPI and hazard quotient among all sampling sites. All sampled tissues were recorded histopathological lesions in both fish. The present study may be considered as an early alert for habitual consumers, particularly at high consumption rates of some fish species.

Highly efficient Bi2Sn2O7/g-C3N4 composite is reported in present work for enhancing the degradation of Rhodamine B (RhB) in the water. The Bi2Sn2O7/g-C3N4 composite was prepared by direct milling the mixture of pre-synthesized Bi2Sn2O7, as a complexing agent, and Graphitic carbon nitride (g-C3N4). The synthesized composites were characterized by the state of art analytical tools such as XRD, TEM, DRS and FTIR spectroscopy. The surface area of C2 composite (42.8 m2/g) was measure from the nitrogen adsorption/desorption data using Brunauer–Emmett–Teller (BET). Bi2Sn2O7/g-C3N4 was found an excellent photocatalyst for the degradation of RhB (91%) in 6 h. The performance enhancement of the photoactivity is because of improved electron-hole separation efficiency due to active electron transfer between Bi2Sn2O7 and g-C3N4 of the Bi2Sn2O7/g-C3N4 composite.

This study was conducted to evaluate the impact of human activities on the ecological health and food chain at the shores of four Nile Islands in Great Cairo including El-Qeratten, El-Waraq, El-Zamalek, and El-Manial. Water quality, bacteria, phytoplankton, benthic algae, zooplankton, macrobenthic invertebrates, and bony fishes were examined at each island shore over two seasons including the lowest and the highest flow (February and July 2020, respectively). The obtained results showed that the average values of most of the chemicals in Nile Island’s water were within the Egyptian water quality limits. Discriminant analysis of physicochemical factors revealed a similarity between El-Waraq and El-Qerateen and between El-Manial and El-Zamalek. El-Qeratten was the most polluted island. It has the highest total and fecal coliform bacteria count (3.155 and 3.050 Log MPN/100 mL, respectively). El-Zamalek shores have the highest phytoplankton (33,582 cells × 104 L−1) and zooplankton count (310,891 organisms × m−3) and phyto-biochemical values. Biochemical analysis of phytoplankton demonstrated the richness of the bulk by protein (> 85% of biomass), indicating that phytoplankton has a high nutritional value. Elevated zooplankton count was recorded at El-Zamalek, which coincided with the peak of phytoplankton abundance. Mollusca were the dominant macrobenthic invertebrates on most of the island’s shores. Bony fishes were represented by 27 species and two crustaceans. The levels of the metals in fish samples were compared with the food safety guideline endorsed by the World Health Organization and Food and Agriculture Organization (WHO/FAO) to evaluate the toxicity level.

This study was conducted to evaluate the impact of human activities on the ecological health and food chain at the shores of four Nile Islands in Great Cairo including El-Qeratten, El-Waraq, El-Zamalek, and El-Manial. Water quality, bacteria, phytoplankton, benthic algae, zooplankton, macrobenthic invertebrates, and bony fishes were examined at each island shore over two seasons including the lowest and the highest flow (February and July 2020, respectively). The obtained results showed that the average values of most of the chemicals in Nile Island's water were within the Egyptian water quality limits. Discriminant analysis of physicochemical factors revealed a similarity between El-Waraq and El-Qerateen and between El-Manial and El-Zamalek. El-Qeratten was the most polluted island. It has the highest total and fecal coliform bacteria count (3.155 and 3.050 Log MPN/100 mL, respectively). El-Zamalek shores have the highest phytoplankton (33,582 cells × 10

Algae provide an alternative, sustainable, and environmentally beneficial method of dyetreatment. In this study, algae were successfully used to remove methylene blue (MB) from aqueous solutions. The effects of several parameters, such as initial concentration of MB (5–25 mg L−1), algae dosage (0.02–0.1 g mL−1), temperature (4, 20, and 30 °C), and contact time (24, 48, 72 and 84 h), on MB removal were investigated. In addition, the characterization of MB before and after treatment was achieved using UV-spectrophotometer and Liquid chromatography-mass spectrometry (LC-MS). The experimental data were applied to three kinetic models, namely pseudo-first-order, pseudo-second-order, and Elvoich. Moreover, Langmuir, Freundlich, Dubinin–Raduskevich (D–R), and Temkin isotherm models were tested. The maximum removal efficiency of MB (~96%) was accomplished at optimum conditions at the initial concentration of MB (15 mg L−1), temperature (30 °C), and algae dosage (0.06 g mL−1) after 60 min of contact time. The removal of MB follows the pseudo-second-order kinetic model (R2 > 0.999), and the experimental data is best fitted by the Langmuir isotherm model (R2 > 0.9300).

This work appraises the extent of toxic trace metals and seasonal pollution degree in Damietta branch sediments of the River Nile of Egypt. The toxic trace metals Fe, Mn, Cd, Co, Cu, Ni, Pb, and Zn were analysed in sediments from six sites during the summer and winter seasons. The metal concentrations and organic matter were determined using inductively-coupled-plasma mass spectrometry and loss-on-ignition, respectively. Multivariate statistical methods were used in order to allocate the possible metals sources and their relationships in sediments. The seasonal mean sequence of toxic trace metals was: Fe &gt, Mn &gt, Zn &gt, Pb &gt, Cu &gt, Ni &gt, Co &gt, Cd. The mean Cd, Pb, and Zn values exceeded the sediment quality guidelines and average shale and they represent severe potential toxicity for aquatic organisms. Cu and Co were enriched during winter. The geo-accumulation index stipulated that metal pollution degree in the sequence of: Pb &gt, Cd &gt, Fe. The highest metal pollution index reported in winter in sites S4/S5 and during summer in sites S4&ndash, S6. Different agricultural, wastewater discharge, fisheries, and industrial activities, as well as the effect of dilution/concentration during summer/winter seasons, are the main factors that contributed to metal accumulations in Damietta branch sediments. Continuous monitoring and evaluation of toxic trace metal concentrations of the Damietta sediments and similar localities worldwide can help to protect the ecosystem from harmful metal contaminations.

The current work describes the sorption potential of Stevia plant for the elimination of the cadmium (II) metal from wastewater. The sorption and kinetics studies were made to understand the way and the best conditions to reach the maximum amount for removal Cd ions by Stevia plant. Nonmodified and modified Stevia plant was used in this study. Stevia was treated with ascorbic acid and the temperature. The results presented that adsorption of the Stevia for cadmium was owing to time, temperature, sorbent dose, and pH. Outcomes presented the modified Stevia is adsorbing better Cd ions better than those nonmodified. Also, the pH of solutions influences the elimination of the heavy metals of cadmium. The maximum value of elimination achieved for cadmium ion by Stevia plant was 92% at pH 5. Many sorption isotherm models were applied. The outcomes find the rate of the sorption process of Cd (II) conformed well to the Langmuir isotherm. The equilibrium of the elimination of cadmium (II) was at maximum at 60 min. The elimination action can be explained by the pseudo-second-order kinetic; the controlling step of elimination can be diffusion. In the end, the outcomes show that Stevia pant is sufficient in eliminating Cd (II) and the activated carbon synthesized with Stevia has enhanced the sorption activity.

YFeO3/g-C3N4 composites with varying weight ratios were prepared following three different methods The optimum weight ratio and the method of preparation for enhanced visible photocatalytic activity towards the degradation of organic contaminants were identified. The successful formation of the composites was proven by XRD and IR measurements. XPS analysis shows that the inactive Y2O3 passive layer on the hexagonal YFeO3 (h-YFeO3) disappeared during the composite formation, resulting in a direct and intimate contact of h-YFeO3/g-C3N4 which is crucial for the photocatalytic activities. The loading of h-YFeO3 varied from 1 to 20% and the highest activity was achieved at 2.4%. At the optimum loading 80% degradation of methyl orange (MO) was obtained under 5 h visible light illumination. The composite photocatalyst shows also modest activity for the photodegrading of 4-chlorophenol (4-CP). Additionally the synthesized composites were characterized by high resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FT-IR) and diffuse reflection UV–vis spectroscopy (DR-UV–vis). In order to determine the relative band positions of the composite photocatalysts their flat band potentials were estimated from Mott-Schottky analysis. Improved charge separation in the composite is mainly responsible for the enhanced photoactivity and supported by photoluminescence experiments.

To study whether the effluents of Sabal drain could affect the health status of Oreochromis niloticus; site2 (south part of main canal), site3 (at the canal outlet), site4 (north part of main canal) and site1 (reference site) were selected. Compared to the reference fish, activities of superoxide dismutase and glutathione peroxidase in addition to glutathione reduced and thiobarbituric acid reactive substances concentrations of the gills showed significant (p

Egypt faces a severe water scarcity in the last years. Increasing population cause rising in water demands and fast economic growth leads to ecosystem degradation. In addition, ineffective irrigation methods with water misuse result in water quality degradation. River Nile is the main fresh water source in Egypt. This study evaluates, one of River Nile branches; Rosetta water quality through Geographical Information System (GIS) techniques. Fifteen water samples were analyzed for their chemical and biological properties. A mathematical model of Water Quality Index (WQI) has been built to integrate biochemical data as input parameters. This model describes the spatial distribution. On the other hand, the temporal of water quality status has been defined. A spatial variation of water quality index was generalized for the study area. The average water quality index values range between 58.8 and 67.2. Generally, the water quality index values within the study area were about the critical pollution level. The concentrations of most elements in the studied water samples were above the permissible levels for drinking water standards. This study concludes that Rosetta water is not suitable for drinking. Furthermore, it can be used for irrigation and domestic uses with specified treatments.

This study was carried out to investigate the seasonal variability and distribution of heavy metals “HMs” (Fe, Mn, Co, Cr, Cu, Ni, Pb, Zn and V) in the bottom sediments of Lake Qaroun, in Egypt. The samples were collected from 10 sites in summer and winter seasons in 2015. Total metals concentrations were measured using inductively coupled plasma spectrometer. Multivariate techniques were applied to analyse the distribution and potential source of heavy metals. The mean seasonal concentrations follow a descending order of Fe > Mn > V > Zn > Cr > Ni > Cu > Co > Pb. The mean concentrations of HMs in sediments during summer were higher than the concentrations during winter and above the average world shale values, except for Pb, suggesting potential adverse toxicity to aquatic organisms. All metals showed enrichment during summer and winter at sites S3 and S5 in the southeastern parts of the lake due to the heavy discharge of contaminants from El-Bats and El-Wadi drains. Principal component analysis results suggested two principal components controlling HMs variability in sediments, which accounted for 63.9% (factor 1: Co, Cr, Cu, Ni, Zn, Pb and V), 15.9% (factor 2: Mn and Fe) during summer, and 76.7% (factor 1: Fe, Co, Cr, Cu, Ni, Zn, Pb and V), 13.8% (factor 2: Mn) during winter of the total variance. Geo-accumulation index (I geo ) showed some pollution risk at the southeastern and southern parts (sites S3 and S5). Dilution during winter, concentration during summer, impact of non-point sources from different agricultural, industrial, municipal sewage and fish farms in the southern part of Lake Qaroun, adsorption and salt dissolution reactions and lithogenic sources are the main controlling factors for HMs in the study area. Monitoring of contaminant discharge at Lake Qaroun should be introduced for future remediation and management strategies.

The Nile River is the major source of water and soils in Egypt. Silt is the main soil component of it. The Nile is one of the international rivers; it passes through ten countries in Africa and is divided into two branches, Rosetta and Damietta at the end of the River. A hydrochemical facies study of the Rosetta branch was done. The geochemical processes which control the water quality and its suitability for drinking, fishing, and irrigation purposes were evaluated. Thus, the hydro-environmental status is studied. Fifteen water samples were collected for determining the physical and chemical parameters. The results show that several parameters are above the desired limits. High concentrations of total dissolved solids (TDS), electrical conductivity, total alkalinity, ammonia (NH3), electrical conductivity (EC), biological oxygen demand (BOD), chloride (Cl−), and sulfate (SO4 2−) were found. While a reduction in dissolved oxygen (DO) in the drains, especially Tala and El Rahawy drains, were noticed. In addition, residual sodium carbonate (RSC), sodium adsorption ratio (SAR), sodium percent (Na %), and magnesium hazard (MH) were measured. The results show that the salinity values for the selected samples minimized their utilization for irrigation. The results indicate that the main geochemical process in the study area is cation exchange and evaporation which control the main ion distribution.

This study investigated heavy metal pollution in sediments of the Rosetta branch of the River Nile of Egypt to quantify the toxic distribution potential of metals into the surrounding environment. Sediment samples were collected at 9 sites during in four seasons. Organic matter and total metal concentrations were determined using loss on ignition and inductively coupled plasma spectrometry, respectively. Principal component analysis has been applied to evaluate the metal sources and the relationships between metals in sediments. Metal concentrations showed the following order: winter > autumn > spring > summer. Mean concentrations of Cu, Zn, Cd, and Pb in sediments were above the average background value of metals in shale. Pb and Cd showed higher enrichment during all seasons at stations N3/N4, Zn at stations N1 to N4, and Cu at stations N6/N8. The variations in heavy metal total concentration and organic matter are due to different input sources, physico-chemical conditions, and adsorption/precipitation/redox conditions in sediments. Mean values of Geo-accumulation index (Igeo) for Fe, Mn, and Cu were below 0 which were classified as unpolluted during spring, summer, and autumn, except Cu increased from unpolluted to moderately polluted during winter. Igeo values for Cd, Pb, and Zn increased from unpolluted–moderately polluted to highly–very highly polluted during autumn and winter. Pollution Load Index was recorded in highest values during winter, especially at Fuwwah/Basioun and in lowest values during summer at after the Edfina Barrage/before Kafer El-Zayat due to industrial/human activities. Both natural and anthropogenic sources contributed to the metal accumulations in sediments, and industrial, agricultural, and municipal sewage effluents discharged from non-point sources may be the main anthropogenic sources for metals in the Rosetta branch.

Hexagonal perovskite YFeO3 was synthesized by a complex-assisted sol-gel technique allowing crystallization at calcination temperatures below 700 °C. As determined by diffuse reflectance spectroscopy (DRS) and Tauc plots, the hexagonal YFeO3 exhibits a lower optical band gap (1.81 eV) than the orthorhombic structure (about 2.1 eV or even higher) being typically obtained at elevated temperatures (>700 °C), and thus enables higher visible light photocatalysis activity. Structure and morphology of the synthesized YFeO3 perovskites were analyzed by powder X-ray diffraction (XRD) and nitrogen adsorption, proving that significantly smaller crystallite sizes and higher surface areas are obtained for YFeO3 with a hexagonal phase. The photocatalytic activity of the different YFeO3 phases was deduced via the degradation of the model pollutants methyl orange and 4-chlorophenol. Experiments under illumination with light of different wavelengths, in the presence of different trapping elements, as well as photoelectrochemical tests allow conclusions regarding band positions of YFeO3 and the photocatalytic degradation mechanism. X-ray photoelectron spectroscopy indicates that a very thin layer of Y2O3 might support the photocatalysis by improving the separation of photogenerated charge carriers.