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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.
显示更多 [+] 显示较少 [-]Mercuric oxide nanoparticles deferred germination and devastated root anatomy of maize
2024
Hassan, Yasser | AbdElgawad, Hamada | Zaki, Ayman | Hammouda, Ola | Khodary, Salah-Eldin
Given the widespread use of mercuric oxide NPs (HgO-NPs), they have become increasingly prevalent in the soil ecosystem. Consequently, it is important to promptly evaluate their phytotoxic impacts. To this end, we have investigated the effects of HgO-NPs (0-200 mg/L) on germination and early growth of maize. Moreover, we have evaluated the interactive influences of HgO-NPs toxicity on the elongation and anatomical structures of primary roots. Relative to control, HgO-NPs decreased the germination percentage, speed and rate, but increased the mean germination time, mean daily germination time and time to 50% germination. The length and biomass of root and shoot and seedling vigour indices have significantly deteriorated. The inhibitory impacts of HgO-NPs on growth parameters were more pronounced in root than in shoot. The response of root was concomitant with dose and time-dependent inhibitions in root elongation and significant drops in root diameter, stele size, cortex size, and cortical cells count. The consequences of HgO-NPs were dose-dependent. For instance, the decrease of maize germination, growth, root elongation, and anatomy were more evident at 200 mg/L HgO-NPs compared to other doses and control. Overall, this study suggests that the presence of HgO-NPs leads to phytotoxic effects on germination and growth of young seedlings, highlighting a noteworthy challenge and environmental concern.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Localized Environmental Pricing of Noise Pollution in Iran
2024
Amini, Fariba | Karbassi, Abdolreza | Amiri, Mohammadjavad
Noise pollution has detrimental negative externalities which Scholars have attempted to evaluate the noise externalities economically, but environmental pricing has not been considerably applied to assess economically noise pollution. The present research aims to quantify the economic cost of noise pollution using the environmental pricing framework proposed by the Delft University. To realize environmental pricing frameworks, this study estimates the costs of noise pollution in the area of Tehran metropolitan. The study attempts to apply the environmental prices framework to local conditions with the assistance of GDP and Gini coefficient. The results demonstrate that the Localized Environmental Prices (LEP) mechanism is capable of internalizing environmental prices. The research indicates that LEP demonstrates the significance of noise pollution necessity to reduction. The results of present investigation show that the sum of environmental prices for noise pollution at Tehran is 56271911 €/year. It also offers a useful foundation for planners and policymakers to make more rational decisions.
显示更多 [+] 显示较少 [-]The geochemistry of strontium-90 in peatlands of the European Subarctic of Russia
2024
Lukoshkova, Anna | Yakovlev, Evgeny | Orlov, Alexander
The subject of this research is the vertical migration of strontium-90 in peatlands of the European Subarctic region of Russia. The activity level of strontium-90 has been determined in peat samples, and the physicochemical parameters of peat deposits have been studied. The specific activity of the radionuclide has been determined using beta radiometric methods with radiochemical preparation according to the methodology. The physicochemical parameters of the peat have been determined using weight-based methods according to the specified procedures. The influence of physicochemical parameters on the vertical migration of the radionuclide in peatlands has been evaluated using correlation analysis. The results have shown that the specific activity of strontium-90 in peat deposits ranges from 0.25 to 7.7 Bq/kg. The results are consistent with typical values for all soils in Russia. The average value of the specific activity of strontium-90 in peat deposits is estimated to be 1.5±0.02 Bq/kg, which is below the established minimum values and average parameters for all soils in Russia. The pathways of vertical migration of strontium-90 in peat deposits demonstrate a downward direction with various trajectories. These pathways serve as a trace of past global atmospheric radioactive fallout. The vertical migration of strontium-90 in peat is associated with the organic matter content, ash content in peatlands, and recent local atmospheric fallout from nuclear fuel facilities. The research results provide valuable information for predicting the migration of strontium-90 into aquifers under changing environmental conditions due to the Arctic's rapid climate warming.
显示更多 [+] 显示较少 [-]Use of Eggshell as a Low-Cost Alternative Adsorbent for Elimination of Fluoride from Groundwater
2023
Assami, Zakaria | Messaitfa, Amar
This paper aims to study the possibility of providing a low-cost alternative for the adsorbents used in the fluoride adsorption from water by using eggshells. Indeed, eggshells were used as an adsorbent for fluoride adsorption from a drinking groundwater sample containing (2.14 mg/l) of fluoride. The eggshells were crushed and sieved into three particle sizes (0.2, 0.5, and 1mm) and then heated at different temperatures ranging from 100 to 250°C. XRD, FT-IR, pHpzc, and TG/DTA analysis were used for the characterization of the adsorbents. Adsorption batch experiments were carried out to determine the adsorption capacity of eggshell powder such as, particle size, preparation temperature, contact time, and adsorbent dose. A spectrophotometer UV-VIS was used to assess fluoride removal efficiency. The eggshell powder heated at 250°C with 0.2mm of particle size was found to be the most efficient adsorbent, with a maximum fluoride removal efficiency of 51.4%, a maximum adsorption capacity of 0.052mg/g, and a residual fluoride concentration of 1.1mg/l within 150 minutes. The data of the adsorption kinetic on ES250°0.2 were successfully fitted with the pseudo-second-order model with a satisfying coefficient of determination (R2=0.993). The results of the intra-particle diffusion model showed a multi-linearity, revealing that the diffusion of fluoride into the adsorbent was by two stages with diffusion rate constants of Ki = 0.007 (mg /g/min1/2) and Ki = 0.001(mg /g/min1/2) for the first and second stage respectively. An adsorbent dose of 1.5g and 1 hour of contact time were sufficient to decrease fluoride concentration from 2.14 to 1.1mg/l.
显示更多 [+] 显示较少 [-]Assessment of Environmental Hazard and Heavy Metal Contamination in Dhaleshwari River Sediment: A Toxicity based Study on Pollution
2023
Islam, Md. Al Sadikul | Hossain, Mohammad Enayet | Nahar, Kamrun | Majed, Nehreen
Developing nations, such as Bangladesh, face an enormous crisis in maintaining natural sustainability due to heavy metal contamination by the peripheral rivers. Frequent heavy metals discharged from tanneries, dyeing, and potential anthropogenic activities in Savar city pollute the Dhaleshwari river, which is an important river of the capital city, Dhaka. The present study aimed to assess the heavy metals contamination in the Dhaleshwari river sediment and evaluate the subsequent ecological risk indices emerging from the deposits. The contamination levels of heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) were analyzed in the Dhaleshwari River sediment. Various environmental indices, such as Potential Enrichment Risk (PER), Geo-accumulation Index (Igeo), Enrichment factor (EF), Toxic unit analysis (TUs), etc., were observed in various compartments. The concentration of heavy metals ranged as follows: Lead (Pb), 297.3-414.6 mg/L; Cadmium (Cd), 1.5-4.4 mg/L; chromium (Cr), 97.9 -282.4 mg/L; Nickle (Ni), 85.1-264.5 mg/L; Iron (Fe), 11800-14375 mg/L. The metal concentrations were higher than the threshold effect level (TEL) and probable effect level (PEL) standards. Based on the TUs, the probability of toxicity is about 76% (TU > 2.3) at the Dhaleshwari river. Comparative evaluation of different environmental indices between present and past studies indicated progressive deterioration of sediments by heavy metals. Linear correlations of heavy metals in sediment samples demonstrated toxic accumulation of heavy metals in the surrounding ecosystem. The study outcomes emphasize the necessity of systematic investigation in the Dhaleshwari river and warranting effective prioritization to ensure river health over industrial wastewater discharge.
显示更多 [+] 显示较少 [-]The Rhizospheric Soil of Sparganium erectum L. Plant: A new Source of Efficient Bacteria for Azo Dye Decolorization
2023
Nikkhah, Masoumeh | Pourbabaei, Ahmad Ali | Shariati, Shayan | Shakiba, Mina
The purpose of our study was to identify the native bacteria with the ability to degrade azo dyes from the rhizosphere of Sparganium erectum L., and Typha latifolia L. plants that were grown on a drain of a textile mill. Eight and one strain with decolorization ability of Cibacron Brilliant Red EB and Terasil Red 3BL-01 were isolated from the saline rhizosphere of Sparganium erectum L. and latifolia L. plant respectively. Results showed that the bacteria isolated from the rhizosphere of Sparganium erectum L. are more capable of decolorizing azo dyes. Based on the 16S rRNA sequencing, selected strains were identified as follows: Enterobacter ludwigii strain SNP3 (OL719291), Rhodococcus fascians strain SNP5 (OL759129), Pseudomonas aeruginosa strain SNP10 (OL759126), and Bacillus safensis strain SNP13 (OL759127). The results of azo dyes biodegradation tests revealed that strains SNP10, SNP3, and SNP5 were more capable of decolorizing 94-97%, 72.53-73.8, 72.53%, and 71.13-73.5% of Cibacron Brilliant Red EB at concentration 10-20 mg/L within 72 h, respectively. Besides, strain SNP13 was the fastest strain in decolorization of Cibacron Brilliant Red EB with 68% and 59% decolorization activity at 10 and 20 mg/L respectively (24 h). Only strains SNP3 and SNP13 could decolorize 83% and 77% of Terasil Red 3BL-01 (30 mg/L), respectively. For the first time, our research findings illustrated that indigenous rhizospheric bacterial strains isolated from Sparganium erectum L. plants have the potential to apply as an azo dye breakdown tool in textile effluent treatment or other ecosystems.
显示更多 [+] 显示较少 [-]Assessment of Concentration and Distribution of Contaminants Using Magnetic Susceptibility Measurements
2023
Anis, Naushi | Kumar, Arun | Arya, Ajay
Magnetic properties are used throughout the world to measure the concentration of (ferri) magnetic minerals in soil, sediment and dust. These minerals in soil come from a variety of sources, including air-borne particulate pollution, parent rock and paedogenesis. Changes in the content of magnetic minerals, as well as their spatial and vertical distribution in soil profiles are caused by human activity. Magnetic minerals are distinguished by their affinity for other elements found in soil, such as heavy metal. As a result, magnetic susceptibility has been widely used as an approximation of heavy metal contamination in soil. The current study was conducted in a tropical deciduous forest in Central Uttar Pradesh, namely the kukrail reserve forest in Lucknow to assess heavy metal contamination levels caused by various anthropogenic activities and to confirm the utility of using MS surveying in these types of studies. The current study was conducted at two sites viz. agricultural area and forest area because these sites are the most contaminated ones. Significant correlation between heavy metal concentration and magnetic susceptibility with p<0.005 is noticed for Co, Cr, Pb, Zn, Cu and Fe of agricultural area. Similarly in forest area significant correlation exists between Cr, Ni, Pb and Zn. The χLF values show a significant correlation with the concentration of heavy metals except for Cu and Cr in forest area and Pb and Zn in agricultural area. In comparison to the methodologies of chemical analysis, the χLF measurement techniques provide us with lower cost and less time consuming method for identification of possible soil pollution.
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