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First Report of Enterobacter hormaechei Isolated from Agricultural Soil in the Biodegradation of Glyphosate
2024
Badani, Hadjer | Haddad, Fatma Zohra | ElOuissi, AbdElKader
Several studies have explored the utilization of soil microorganisms, to address the environmental issues associated with glyphosate use and enhance crop yields. In our investigation, screening on Agar plate and broth medium Luria Bertani was carried out after isolating bacterial strains from rhizospheric agricultural soil in Mascara, Algeria, to biodegrade glyphosate, following that by testing the Plant Growth-Promoting Rhizobacteria and evaluate the effects of glyphosate on these proprieties. Our findings indicate that five bacterial strains exhibited growth in the presence of glyphosate concentrations up to 25 mg/ml, beyond this concentration the strains have developed tolerance. Following a partial examination of the 16S rRNA sequences, the bacterial strains were identified as belonging to the genus of Enterobacter. After 10 days of incubation with the glyphosate, Phosphate solubilization decreased in broth and agar Pikovskaya medium and the bacterial strains synthetized less of indole-3-acetic acid compared to the control, indicating the impact of glyphosate on these outcomes, high concentration of glyphosate inhibited nitrogen fixation, and various doses of glyphosate were found to restrict the growth of biofilms in these strains. The results of HPLC examination of secondary metabolites revealed that the primary degradation products of glyphosate in all strains were Sarcosine and Glycine. So, it seemed that the strain could both biodegrade glyphosate and use it for growth ,while also possessing rhizobacteria properties that promote plant development, enabling the use of the strains in the bioremediation of glyphosate-contaminated soils.
Afficher plus [+] Moins [-]A Simulation to Assess the Probability of the Spread of Radioactive Materials from the Zaporizhzhia Nuclear Power Plant using the HYSPLIT Model
2024
Valizadeh, Behshad | Heydarizade, Yassin | Tayebi, Javad | Rezaie, Mohammad Reza
Today, world pollution is increasing, and many pollutants such as radioactive elements enter to environment through human activity contaminants play an essential role in human life and health. Therefore, the examination of models for dispersion caused by radioactive substances is an important issue. This article is a simulation study of the hypothetical scenario of the Zaporizhzhia Nuclear Power Plant (ZNPP) in Ukraine, which is one of the NPPs in Europe. This scenario includes the occurrence of an accident in the power plant that entry of pollutants to environment and creates an environmental disaster. The simulation of this scenario was done using the Hyspli4 )Hybrid Single-Particle Lagrangian Integrated Trajectory) model and NOAA website data of ZNPP (include the wind information, temperature, humidity, and atmospheric pressure in different spatial and temporal scales) to predict and deal with pollutants. The simulation was conducted in the first week of April 2023 for 131 I and 137Cs elements, which are important elements that come out of the power plant and cause many problems. The results show the highest annual dose and concentration are 4.6 mSv/year and 2.7E+06 Bq.s/m3 respectively. It also shows that in the event of pollution, the entry of contaminated materials into the Dnieper River and the western edge of the blackened sea will bring a great disaster. Also, the eastern and northeastern regions of Ukraine, especially Kharkiv and the western borders of Russia, lead to pollution that causes radiation hazard, so the news should be shared with everyone before an actual incident occurs.
Afficher plus [+] Moins [-]Ecological Risk Assessment of the Soil around Odo Iya-Alaro (Iya Alaro River) at Ojota, Lagos States, Nigeria
2023
Adio Hassan, Isiaka | Abdul Raheem, Wahabi Olaitan | Adejoke Obalola, Aishat | Oluwole Bello, Isiaq
Human developmental activities always result to waste generation; that invariably pollute the environment, if not properly managed. The aim of this study is to determine soil quality around Odo Iya-Alaro at Ojota, Lagos. A total of 12 soil samples were collected from 0 -15 cm and 15- 30 cm at three different spots of 100 and 500 m (control) away from the bank of the river. Samples were analysed for pH, EC, NO3, TOC; Zn, Na, K, Ca, Mg, Cu, Fe, Cd, Cr, Ni, and Pb using standard analytical methods. The results were subjected to both differential and inferential statistics using statistical package (SPSS 22.0 version). Subsequently, the data were compared with Earth crust values. The soil pollution was evaluated using pollution, ecological risk, and geo-accumulation index. Cr (50.43), Ni (29.47), and Cu (104.10) mg/kg at 100 m were higher than their controls; (12.09), (8.14), and (86.06) mg/kg respectively, but lower than their respective Earth crusts; (100), (80) except (50) mg/kg. The soil was moderately polluted with pH (1.15), Na (3.00), K (2.11), Mg (1.87), Ca (1.26) and Cu (1.21); considerably polluted with EC (3.82), TOC (3.39), and Ni (3.62); and very highly polluted with Fe (8.26). Fe (711.73) had a very high ecological risk. The Geo – accumulation index was moderately - strongly polluted with Zn (2.61), and very strongly polluted with pH (5.37), EC (14.90), NO3 (9.66), Na (15.41), K (11.31), Mg (9.51), Ca (17.08), Fe (15.32), Cu (12.54), Cr (8.67), and Ni (7.32). The soil was polluted. and urgently needs reclamation for Garden Park (relaxation).
Afficher plus [+] Moins [-]Assessment of the limnological characteristics of Lake Bosomtwe in the Ashanti Region of Ghana
2022
Owusu-Boateng, Godfred | Ampofo-Yeboah, Akwasi | Agyemang, Thomas Kwaku | Sarpong, Kofi
The quality of the water from Lake Bosomtwe was assessed to aid in the conservation decision on the lake. Twenty-six parameters of physico-chemical, bacteriological, and organic effects and major and trace ions were evaluated using the principal component analysis. The levels of these parameters were also compared with surface water benchmarks of Ghana EPA, WHO, EU, US EPA and CCEM. As prescribed by the benchmarks of these regulatory bodies, the mean levels of temperature, pH, dissolved oxygen, total suspended solids, total dissolved solids, nitrates, phosphate, biochemical oxygen demand, chemical oxygen demand, total hardness, conductivity, alkalinity, turbidity and fluorine did not signal any lake pollution, but sulphate, total and faecal coliforms, chlorophyll-a, cadmium and mercury showed pollution tendencies. Temperature, pH, dissolved oxygen, total suspended solids, total dissolved solids, nitrates, phosphate, sulphate and total coliform bacteria were found to be the main parameters that drive 71.2% of the limnological characteristics of the lake water and deserve careful consideration in designing conservation strategies for the lake.
Afficher plus [+] Moins [-]Assessment of groundwater and surface water pollution by hazardous metals, using multivariate analysis and metal pollution index around the old Sidi Kamber mine, NE Algeria
2022
khelfaoui, malika | Benaissa, Amina | Kherraf, Sihem | Madjram, Mohamed Salah | Bouras, Ibtissem | Mehri, karima
In order to evaluate the impact on water quality of the abandoned Sidi Kamber mine in Skikda, NE Algeria, Pb, Zn, Cd, Fe, Cu, Mn and Ni metals were collected at surface water and groundwater, from twenty eight sites located near the mine. Conventional hydrochemical methods, heavy metal pollution index (HPI) and multivariate statistical analysis techniques: correlation matrix (CM), principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used. Surface water results show that El-Souk River has a high level of pollution, but Guenitra dam water is less contaminated. Regarding the groundwater results, the wells and springs are not suitable for drinking. The overall quality estimated by HPI values of surface and groundwater are poor; they may pose a potential health risk to the local population. The PCA and HCA suggest that surface water and groundwater are contaminated by two sources: anthropogenic and natural. According to the obtained results, surface water and groundwater pollution state of this area raises serious concerns about health and environment.
Afficher plus [+] Moins [-]Arbuscular mycorrhizal fungi prevent mercury toxicity in Lactuca sativa (L.) seed germination
2022
Escobar-Vargas, Sebastián | Vargas Aguirre, Carlos | Rivera Páez, Fredy
Mercury pollution is an issue of global concern. In Colombia, the use of contaminated water for food crop irrigation and artisanal mining contributes to mercury pollution in soil, affecting food production and restoration of disturbed areas. Mycorrhizal fungi are symbionts that provide benefits to plants including resistance to heavy metals, but fungal effects on germination remain to be fully described. This study tested the effect of mercury and mycorrhizal fungi on Lactuca sativa seed germination. A 2x5 completely randomized factorial experiment was developed to assess the effect of five HgCl2 polluted treatments, two mycorrhizal treatments (i.e., with inoculum, without inoculum), and the interaction of both factors on seed germination, seedling root colonization, pH, and final water content. In samples with no mercury pollution, mycorrhizal fungi had an inhibitory effect on seed germination. Likewise, the effect of mercury on seed germination is significantly inhibitory. However, pots inoculated with arbuscular mycorrhizal fungi showed constant germination probabilities, independently of mercury concentration. According to the best model determined for the data, a key step in the mitigation of mercury toxicity in seed germination is to prevent substrate pH changes. The environmental conditions of the experiment contributed to densely activate populated biomass of inoculum, which promoted root invasion from various points. Overall, the presence of mycorrhizal fungi in seedbeds could lead to a reduced number of plant individuals. However, the use of fungal inoculum in polluted environments, highly contributes to plant establishment, which is relevant in further vegetable cultivations growing in soil polluted areas.
Afficher plus [+] Moins [-]Analysis of heavy metal concentration in some vegetables using atomic absorption spectroscopy
2021
Abrham, F. | Gholap, A.V.
This study assesses heavy metal levels in water, soil, and vegetables (swiss chard, lettuce, cabbage, collard green, tomato, green pepper and carrot) irrigated with waste water in Gamo, Ethiopia. The samples of soils, water, and vegetables were randomly collected, processed, and analyzed for heavy metals using atomic absorption spectrophotometry. The results obtained show that the irrigational water is profoundly contaminated with heavy metals Cd, Cr and Ni and Pb, Zn and Cu had the lowest concentration in irrigation water. The levels of Cd in Kulfo river area and Chamo Lake area and Ni in most of the farm soils were also found to be higher than the guideline values. The study also revealed that the mean levels of Cd in most vegetables and Cr and Pb in some vegetables were higher than the maximum recommended limits set by WHO/FAO. In general the results show that the highest concentration of the heavy metals was obtained from Kulfo river area compared to the Arbaminch textile share company area, Abaya Lake area, and Chamo Lake area. Cabbage was maximally contaminated with potential toxic elements followed by Swiss-chard, carrot, tomato, collard green, green pepper and lettuce. Hence, from kulfo river area frequent consumption of cabbage and Swiss chard may cause serious health risks to consumers. The levels of many elements were found to vary with location, suggesting localized inputs of the various contaminants related to industrial and other activities that generate wastewater. This study recommends regular monitoring of heavy metals in soils, waters, and foodstuffs to prevent excessive accrual in food chain.
Afficher plus [+] Moins [-]The Effectiveness of the Ballast Water Exchange Method in Removal of the Heavy Metals in the Ballast Tanks of the Ships, Bushehr Port- Persian Gulf
2020
Tolian, R. | Javadzadeh, N. | Sanati, A. M. | Mohammadi Roozbahani, M. | Noorinejad, M.
Ships transport about 80 percent of world trade and transfer approximately three to five billion tons of ballast water internationally every year. Due to the likely presence of pollutants, the ballast water discharged by ships can have negative effects on aquatic ecosystems. This study was conducted on 10 ships that entered the Bushehr port to determine the effectiveness of the ballast water exchange method and also to specify the contents of heavy metals (Ni, Cd, Pb and Cu) in the water and sediment of the ships’ ballast tanks. The samples were collected from January 2017 to July 2018 during a cold and a hot season. The results indicate the values of heavy metals in the samples in this order: Ni> Cu > Pb > Cd. The heavy metals concentrations in the sediment samples did not exceed the standard of the National Oceanic and Atmospheric Administration (NOAA). Whereas, Cu and Ni in all water samples and Cd in samples 2 and 7 exceeded the NOAA quality standard value. A correlation analysis of the metals showed that the sources of heavy metals vary in water and sediment samples, except for Pb and Cu in sediment samples which a positively significant relationship were observed. The results also revealed that the ballast water exchange method cannot by itself be effective and an efficient management together with continuous monitoring seems to be essential to prevent pollution of the ballast tanks of the ships entering the Bushehr port.
Afficher plus [+] Moins [-]Effect of Heavy Metals on the Growth of Total Phytoplankton Load
2019
Khatun, M. | Alam, A. K. M. R.
The experiment was performed to evaluate effect of heavy metals on total phytoplankton load (TPL) using water of Turag River adjacent to Ashulia locating on the north-eastern side of Dhaka city, Bangladesh. Total phytoplankton load comprises of Euglena sp., Borodinella sp., Pediastrum biradiatum, Pinnularia sp., Fragillaria sp., Fragillaria crotonensis, Gloeocapsa sp., Navicula sp., Cynedra sp., Crucigenia sp., Chlorella sp., Spirogyra sp., Phacus acuminatus, Phacus circulatus., Nitzschia sp. and Nitzschia clausii. Phytoplankton load showed the abundances Bascillariophyceae (43.75%) > Chlorophyceae (37.50%) > Euglenophyceae (18.75%). The average maximum growth rate (log transformed) of TPL in control culture was -0.25μg/l and treated cultures using 1ppm, 3ppm, 5ppm, 7ppm concentration of heavy metals (Zn and Cu) were 0.03 μg/l, 0.03 μg/l, -0.11 μg/l and -0.26 μg/l, respectively. In treated culture using 1ppm concentration of heavy metals (Zn and Cu) the growth rate of phytoplankton load increased significantly whereas the growth rate decreased at higher concentrations (3ppm, 5ppm and 7ppm) of heavy metals. The implication of this finding can be used to monitor health of riverine ecosystems and management of river pollution.
Afficher plus [+] Moins [-]Review of Heavy Metal Accumulation in Aquatic Environment of Northern East Mediterrenean Sea Part II: Some Non-Essential Metals
2018
Yilmaz, Ayşe | Yanar, Alper | Alkan, Ela
Heavy metals that enter marine environment and remain in the water as well as the sediments are accumulated by aquatic organisms, thus becoming highly good indicators to monitor metal accumulation in the long run. Metals are potentially harmful to humans and most organisms at varied levels of exposure and absorption. Northern East Mediterranean Sea is a crucial region as it is an area, shared by numerous aquatic species with pollutant factors such as heavy marine traffic, transportation ports, industry plants, iron and steel works, oil pipeline installation, and other small factories. While the previous part of this review (Review of heavy metal accumulation on aquatic environment in Northern East Mediterranean Sea part I: some essential metals) evaluated the data from previous studies concerning toxic effects of selected essential metals on seawater, sediment, and different tissues of aquatic animals, collected from different areas in Northern East Mediterrenean Sea since the 1990s, the present part intends to evaluate the data from previous studies on toxic effects of selected non-essential metals. For this purpose, 94 articles and 6 theses have been examined and a good deal of information has been gathered to open a forward-looking view of the studied area’s pollution. Althought there has not been any harmonization, when comparing heavy metals investigations in the bay, all studies have shown that consumption of aquatic species from the region causes no problem to human health.
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