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Examination of Medicinal Plants for Radionuclide Absorption and their Health Implications
2024
Popoola, Felix | Isola, Oladotun | Fakeye, Oluseye | Owolabi, Tunde | Sanyaolu, Modupe | Owoyemi, Sheu | Elijah, Isaac
This study examined the concentrations of 40K, 238U, and 232Th radionuclides and evaluated the possible radiological health risks to medicinal plants found in Ewu, Edo State, Nigeria, using a NaI(Tl) gamma spectrometer. The six selected medicinal plants were Mangifera indica, Dacryodes edulis, Terminalia catappa, Cymbopogon citratus, Anacardium occidentale, and Persea Americana. The results showed that the activity concentrations for 40K ranged from 146.59 ± 4.81 in Persea americana to 296.08 3.42 Bq/kg in Cymbopogon citratus, with a mean of 209.43 ± 5.14 Bq/kg; 238U ranged from 2.25 ± 0.06 to 5.57 ± 0.15 Bq/kg, with a mean of 4.73 ± 0.15 Bq/kg; and 232Th varied from 4.50 ± 0.35 to 12.07 ± 0.57 Bq/kg, with a mean of 8.00 ± 0.40 Bq/kg. The maximum and minimum activity concentrations of both 238U and 232Th were found in Mangifera indica and Cymbopogon citratus, respectively. The calculated average committed effective dose ECED was 0.130 μSv/yr and the excess lifetime cancer risk (ELCR) has a mean of 0.00913 (×〖10〗^(-3)). The radiological hazard assessment of the investigated medicinal plants was well within the internationally recommended safe limits of 0.3 mSv/yr and >〖10〗^(-4) for ECED and ELCR respectively. 232Th contributes 54.91% of the total ECED, while 238U contributes the least to 6.35%. 232Th exhibits a very strong, positive, and significant relationship with ECED and the ELCR, and it contributes largely to the ECED and ELCR due to ingestion of the examined herbal plant. Therefore, these medicinal plants are radiologically safe for human consumption.
Afficher plus [+] Moins [-]Removal of microplastics from synthetic wastewater via sono-electrocoagulation process: modeling and optimization by central composite design
2024
Ghadami, Mahshid | asadi-Ghalhari, Mahdi | Izanloo, Hassan | Alasvand, Shokoufeh | Tabatabaei, fatameh sadat | Mostafaloo, Roqiyeh | Omidi Oskouei, Alireza | Ghafouri, Nasim
Wastewater treatment plants are an important pathway for microplastics (MPs) to enter the environment. In recent decades, hybrid treatment technologies such as sono-electrocoagulation have been used to treat various types of wastewater. This study aimed to remove polypropylene microplastics from synthetic wastewater by sono-electrocoagulation process using central composite design. The central composite design was utilized to investigate the relationship among four independent variables including the number of MPs (0.003-0.03 MPs/L), sodium sulfate concentration (180-9000 mol/L), voltage (1-15 V) and reaction time (20-180 min) on the efficiency of polypropylene microplastic. Design Expert 13 software and central composite design method were used to design and analyze the experiments and results. The optimum number of concentration of MPs, sodium sulfate concentration, voltage, and reaction time were found to be 6343.36 MPs/L, 0.0181924 mol/L, 10.0356 V, and 62.21 min, respectively. In optimal conditions, polypropylene removal was found to be %90.34. Central composite design proposed a quadratic model for this process. Adequacy of the model using lack of fit statistical tests values, p-values, and F-values was checked, yielding the values of were 1.76, 0.0001 ˂, 19.51, respectively. The R2, R2 adjusted, R2 predicted values which were 0.9367, 0.8776, 0.6959, respectively. Considering the proper removal efficiency, the sono-electrocoagulation process can be used to remove microplastics.
Afficher plus [+] Moins [-]Treatment of Textile Wastewater Through Constructed Wetland Coupled Microbial Fuel Cell by Canna indica
2024
Sheoran, Deepika | Singh, Simranjeet
Constructed wetland coupled microbial fuel cell (CW-MFC) encompasses both aerobic and anaerobic zones to produce electrical energy while facilitating the oxidative breakdown of pollutants. In this study, we ascertained the effective setup of CW-MFC in order to assess the pollutant removal efficiency and electricity generation. The CW-MFC system was initially filled with textile wastewater. Stainless steel mesh with granular activated carbon as the anode and graphite rods as the cathode were used. Soil and gravel were used as substrates and Canna indica as macrophyte. Over the course of 4 weeks, regular assessments were conducted every 3rd day to monitor the alternations in the wastewater properties. Throughout the treatment phase, the planted CW-MFC system achieved a significant reduction in phosphate, nitrate, BOD, COD, and chloride as compared to the unplanted CW-MFC system. From this study, the results also show that planted CW-MFC produce maximum peak voltage (0.112V) and current (1.12 mA) in comparison to CW-MFC without plants. Consequently, the finding suggests that Canna indica possesses the capacity to treat textile wastewater.
Afficher plus [+] Moins [-]Bioremediation: Assessment of Growth Attributes of Maize (ZEA MAYS) on Crude oil-Polluted Soils
2024
Agbor, Reagan | Asuquo, Eno | Ivon, Ettah | Ellen, Simon
Environmental pollution has posed a major threat to terrestrial, aquatic, and marine ecosystems, thereby affecting microflora and micro-fauna populations. This study assessed the growth attributes of maize plants on crude oil-polluted soils amended with agro-wastes. Six kilograms each of composite soil sample was weighed and transferred into one hundred and fifty labeled plastic buckets with drainage holes for soil aeration and spiked with 300mls each of crude oil, allowing for 14 days of soil acclimatization. Soil amendments such as groundnut husks, cassava peels, empty fruit bunch of oil palm, and maize cob powder were applied and allowed for 90 days. Maize seeds were sowed, while periodic data were collected and subjected to a three-way ANOVA. The result obtained revealed that maize seeds grown on agro-wastes treated and pristine control soils show early seed germination than the crude oil-polluted control soil. The plant height obtained for GnH14P + MaC14P at 10% was the highest with a mean (of 152.81cm2), and the leaf area of the maize from soil treated with GnH14P + EFBOP14P at 10% had the highest mean (756cm2), the leaf length of maize from soil treated with GnH14P + CasP14P at 3%, 6%, and 10% was the highest with mean ranging (54-97 cm2) with no significant difference in mean values obtained. The stem girth, number of leaves, and leaf width were generally improved in the bio-remediated soils. The result for the yield performance of maize shows that the days to flowering were shortened in the bio-remediated soil compared to the prolonged flowering days observed in the crude-oil polluted control. The number of seeds per cob was high in the bio-remediated soils while no seed was obtained in the crude-oil-polluted control soils. It can be concluded that the ameliorated treatment with the agro-wastes improves the performance of maize plants in crude oil-polluted soils.
Afficher plus [+] Moins [-]Modeling Airflow in Urban High-Rise Building Areas and Climate Comfort
2024
Zahedifar, Tahmineh | Darabi, Hassan
Urban morphology impacts micro-climates, solar energy absorption, air flow, wind patterns, energy consumption, and air pollution concentration. Temperature control in public spaces reduces heat island formation, while ventilation corridors potentially improve air quality. However, despite the literature on airflow and urban tall buildings providing valuable insights, further research is needed to understand the complex relationship between airflow patterns and urban high-rise buildings. This research should consider factors such as landscape types, building height, density, and orientation. This research aims to examine airflow patterns in high-rise buildings that are influenced by nearby land use, which can impact ventilation and climate comfort. To investigate these objectives, we utilized the Universal Thermal Climate Index (UTCI) and Predicted Mean Vote Index (PMV) by conducting simulations using ENVI-met software. The results revealed that buildings with narrower widths have better wind warded front conditions, while those with an unfavorable wind angle or a narrow facade are less comfortable. Public spaces that face the wind benefit from improved ventilation. It is essential to consider the optimal arrangement, ventilation, and height of buildings to ensure the favorable airflow. Factors such as the placement of trees, the use of porous walls, water features such as fountains and sprinklers, and the local climate all contribute to creating better wind conditions. Investigating the reciprocal interaction between the landscape, high-rise buildings, and climate comfort could be considered in future research.
Afficher plus [+] Moins [-]Assessing Heavy Metal Contamination In Surface Water And Sediments Of The Tafna River (North-West Of Algeria)
2024
Mechouet, Ouezna | Foudil Bouras, AliEddine | Benaissa, Noureddine | Ait Hamadouche, Yasmine | Haddad, Fatima Zohra | Dimache, Alexandru
Water and sediments have become a major threat. Heavy metals, some of which are potentially toxic, are distributed in different areas by different routes. Tafna river was studied upstream and downstream under contrasting hydrological conditions during the year 2020.The different levels and sources of pollution are assessed by combining geochemical indicators: geoaccumulation index (GI-go), contamination factor (CF), pollutant loading index (PLI) and supplemented by correlation matrix (CM) as statiscal analyses added principal component analysis (PCA). The elements analysed were physical and chemical parameters (pH, DO, electrical conductivity CE and, COD BOD5), and the metallic elements (Fe, Cd, Pb, Cu, Mn and Zn). They were classified based on how contaminated they were: for the water compartment (Fe> Mn>Cu>Pb>Cd>Zn), while for sediments (Zn> Pb>Fe>Cd>Cu >Mn). The results suggest that the chemical composition of the waters of the Tafna river is influenced by the lithology, which contributes to the enrichment of the sediments. All of the indicators suggest an average levels of sediment and water pollution at the Tafna's summit, then decreases towards the bottom due to the geomorphology with multiple sources of pollution. As a result, our study offers the first comprehensive information on the amount of heavy metals present in the riverbed's sediment and water.
Afficher plus [+] Moins [-]Determination of Radon Gas Concentration in the Water of Midelt Region, Morocco, Using a Nuclear Track Detector (LR-115) and Assessment of Radiological Health Risk
2024
Said, Khadour | Brahim, Sedra Moulay | Abderrahman, El boukili | El-Taher, Atef
The article aims to assess radon concentration in various water samples, revealing levels ranging from 0.53 Bq/L to 4.68 Bq/L. Radon, specifically the isotope 222Rn, is a naturally occurring radioactive gas formed during the decay of the 238U decay series, originating from the breakdown of 226Ra. This gas is commonly found in rocks, soil, natural gas, and groundwater. Exposure to airborne and waterborne radon can increase the risk of certain cancers due to human radiation exposure. The primary Aim of this study was to assess the concentration of radon in water samples collected from diverse regions of Morocco, particularly the Midelt province and the Draa-Tafilalt region located at coordinates 32° 40' 48″ North, 4° 44' 24″ West. For this purpose, Solid State Nuclear Track Detectors of the LR-115 variety were used. The evaluations of annual effective dose equivalents exhibited a range spanning from 11.51 to 1.30 μSv/y, showcasing a consistent pattern of decline. Correspondingly, projections of excess lifetime cancer risk encompassed a spectrum from 4.00 to 1.98. Significantly higher risks were associated with samples S1 and S2, while notably lower risks were tied to S14 and S15. It is worth noting that all the water samples subjected to analysis registered annual effective doses that fell within the global average level recommended for ingestion exposure dose values (0.23 mSv/y) by the United Nations Scientific Committee on the Effects of Atomic Radiation. Given these results, there seem to be no radiation risks from radon gas in the study area.
Afficher plus [+] Moins [-]Satellite-Based Chlorophyll-a Analysis of River Tapi: An Effective Water Quality Management tool with Landsat-8 OLI and Acolite Software
2024
Punde, Bhagavat | Jariwala, Namrata
Most pollutants found in rivers come from the discharge of raw sewage from both point and nonpoint sources. So, monitoring the pollution levels in surface water sources is essential. River pollution monitoring is a real challenge. Using remote sensing, precise outcomes can be achieved with the help of the selection of the right combination of satellite images and algorithms. Generally, established available algorithms are site-specific, indicating that they may not work at all areas on Earth's surface due to differences in altitude, cloud cover, and sun glint. The present work determined Chlorophyll-a concentrations in the Tapi River at various locations using Landsat-8 satellite images and Acolite software from 2017 to 2021 Period. The outcomes reveal that applying the dark spectrum fitting with sun glint correction when processing Landsat-8 satellite images is needed. In the present study, water quality results were obtained very precisely for the months of January, February, November, and December after processing and analysing satellite images. Due to factors such as sun glare, cloud cover, cloud shadow, and haze, the desired effect could not be achieved in the remaining months of the study period. This research provides a solid foundation for estimating the impact of eutrophication in the water body by estimating chlorophyll-a concentration from satellite images.
Afficher plus [+] Moins [-]Concentration of Selected Phenolic Compounds in Effluent, Stream and Groundwater of a Local Textile Industry in Abeokuta, Ogun State, Nigeria
2024
Olayinka, Olufunmilayo | Egbeyemi, Morenikeji | Oyebanji, Adedayo
Phenols have attracted global interest in the sphere of environmental management due to their potential toxicity on human health. This study determined concentrations of three priority phenolic compounds in effluent and water of a local textile industry in Abeokuta, Nigeria. During tie-dye production, triplicates of effluent, well water, stream and control water were collected three times from five points to give a total of forty-five samples. Physicochemical parameters of samples including temperature, pH, electrical conductivity (EC), total suspended solids (TSS) and total dissolved solids (TDS) were determined according to standard methods while the concentrations of the priority phenolic compounds (4-nitrophenol, 4-chloro-3-methylphenol and 2, 4-dinitrophenol) were determined using High Performance Liquid Chromatography equipped with Ultra-Violet detector (HPLC/UV). Data obtained were subjected to descriptive (mean and standard deviation) and inferential (ANOVA) statistics. pH, EC and TSS of effluent and water samples were higher than the permissible limits of World Health Organization (WHO) and Federal Environmental Protection Agency (FEPA) while temperature of the effluent samples and TDS of the well water samples were within standard values. Higher concentrations of the priority phenolic compounds occurred in effluent than water samples but 4-nitrophenol was below detection limit (DL) in water samples. Concentrations of 4-nitrophenol, 4-chloro-3-methylphenol and 2,4-dinitrophenol in effluent exceeded stipulated standard of WHO (0.01 mg/L) and water samples. High concentrations of phenols in water bodies at the local textile industry suggest uncontrolled discharge of effluent from the industry which could eventually reach surface and ground water with potential significant health implications to the populace.
Afficher plus [+] Moins [-]The Effect of Magnetic Treatment on some Physico-Chemical Properties of Landfill Leachate (Wadi Al-Hada)
2024
Ahmad, Adnan | Soubh, Alaa Mohamad
The landfill leachate contains high concentrations of organic pollutants that can be biological and resistant to it. Therefore, the resulting leachate must be treated from the healthy landfill before disposing of it in the environment. In this research, the technique of improved magnetic therapy was tested to improve some physicochemical properties of landfill leachate. Where a laboratory model was designed to evaluate the performance of the magnetic field with different strengths on the treatment of the leachate field collected from the Wadi al-Hadda landfill in Tartous Governorate-Syria. By the increasing in magnetic field strength from 272 to 678 µT, the removal efficacy of BOD and COD increased from 9 and 19% to 36.7 and 54.7%, respectively, and, the removal efficacy of NO3-N and NO3 increased from 6 and 17% to 24.6 and 46.8%, respectively. Electric conductivity (EC) values also decreased due to the use of magnetic field.
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