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Bioremediation of Heavy Metals by Use of Bacteria
2022
Orcan Demircan | Abdul Razaque Memon
Heavy metal pollution generally occurs due to socio-economic, industrial, and anthropogenic activities, which may cause an environmentally hazardous and serious severe threat to the survival of the organisms (genotoxic, carcinogenic, and clastogenic effects on it). Many physical and chemical remediation approaches have been proposed to deal with this pollution, but these are very time-consuming and costly. While bioremediation stands out as an inexpensive and efficient approach, the use of bacteria is thought to be a potential and productive organism to prevent this pollution. This review has evaluated the bacterial potential to clean up heavy metals from the environment and elucidated the mechanisms responsible for bioremediation.
显示更多 [+] 显示较少 [-]Assessment of Metal Levels in Biotic and Abiotic Materials from Giresun Forests
2020
Mustafa Türkmen | Aysun Türkmen | Ayhan Kara
The study investigated the metal levels in biotic and abiotic materials from Giresun forests. While soil and water samples were selected as abiotic materials, leaves and moss were selected as biotic materials in forest. These selected materials were sampled from six stations. All samples were analyzed three times for arsenic, iron, chromium, copper, manganese, nickel, lead and zinc by ICP-OES. A logarithmic transformation was done on the data to improve normality. One way ANOVA and Duncan’s multiple range tests were performed to test the differences among metal levels of stations. The differences among metal levels in stations were statistically significant (p
显示更多 [+] 显示较少 [-]Determination of Molybdenum Contents and Relation of Some Heavy Metals in the Soil of Meadow-Pasture Terraces Between Kırıkhan-Reyhanlı
2019
Mehmet Yalçın | Kerim Mesut Çimrin
This study was aimed to determine the molybdenum content of meadow - pasture soil between Kırıkhan and Reyhanlı in Hatay province and to determine the relations of the molybdenum content with some heavy metals in the soil. For this purpose, two different depths (0-20 and 20-40 cm) representing grassland pasture lands and 80 soil samples from 40 different points were taken. Cadmium (Cd), Cobalt (Co), Nickel (Ni), Lead (Pb), Copper (Cu), Iron (Fe), and Molybdenum (Mo) contents were determined in the soil samples. The contents of the available Cd, Co, Pb, Cu, Fe, Ni and Mo of the soil were determined by reading the 0.005 M DTPA + 0.01 M CaCl2 + 0.1 M TEA extracts in the ICP instrument. The results of the research shows that the Cd contents of the soils are between 0.01-0.32 ppm; Co contents are from 0.01 to 4.97 ppm; Ni contents 0.00 to 20.00 ppm; Pb contents 3.00-67.00 ppm; Cu contents 0.26-7.48 ppm; The Fe contents are between 4.00 and 61.00 and the Mo contents are between 0.001 and 0.064 ppm. It was determined that there are significant positive relationships between Co, Ni, Pb, Cu and Fe contents of Mo in the soil. It was also determined that there are significant positive significant relationships between Cd and Co; Co with Ni, Pb, Fe and Pb and Cu, Fe and Cu and Fe. No heavy metal pollution was found when the heavy metal contents of the regional soils were compared with the limit values.
显示更多 [+] 显示较少 [-]Conformity of Fruit Nectar Samples to Libyan Specification Standards
2016
Ahmeda Algari Alzagtat | Rema Yousef Eledody
The aim of this study is to evaluate the quality characteristics of physical, chemical and microbiological of some fruit nectar samples produced from some local and imported companies and sold in the city of Tripoli, and to determine their conformity with Libyan specification standards. In this study, 40 samples of different fruit nectars (grape, pineapple, guava, orange, apple, and mixed fruits) were collected from different local supermarket, five imported companies and 4 domestic which were available at the time of study. The Samples were classified based on their type of fruit nectars and also marked as (A, B, C, D) and (E, F, L, M, N) for different domestic or imported and imported companies respectively. The results showed that all the samples were free from artificial colours added. Local and imported samples were conform with the Libyan specification standards (990-2014) for fruit nectars. Five local and four imported samples were unconfirmed with the standards. In terms of acidity, some local and imported samples were conform to the Libyan specification standards, except one local sample and 5 imported samples. However, 35.3% of local samples and 43.5% of the imported samples unconfirmed to the Libyan standard specifications. Microbiological results showed that all local and imported samples were free from total bacterial count, yeasts and molds and coliform bacteria. Heavy metals (cadmium, lead, arsenic, copper, zinc, iron) of local and imported samples were conform to the Libyan specification standard, except 3 samples of imported products were had higher arsenic concentration. Based on the results of this study which indicated the importance of quality control programs for such products not only during production but also during storage and sales due to possibility of contamination and spoilage.
显示更多 [+] 显示较少 [-]Determination of Heavy Metal Remediation to Soil from Community Buildings’ Rooftop
2022
Yasin İlhanlı | Erman Ulker
Considering the importance of water in the world, the amount of usable water is not sufficient throughout the world, the existing available fresh water resources are not enough, therefore, water shortages may be encountered in the following years. Keeping the quality of water as it is demanded gains more importance than before. Particularly, heavy metals begin to interfere with groundwater resources, and the quantity of pollution growing due to industrialization, and urbanization. In the present study, the quantitative analysis of heavy metals in harvested rainwater from the rooftop of public buildings in Bornova, Izmir is investigated. The results show that a minimum of 5 μg of copper, 4 μg of zinc, 2.69 μg of lead, 0.095 μg of cadmium, 0.55 μg of chromium, 89,7 μg of iron, 0.96 μg of arsenic, 0.0119 μg of mercury and 3.88 μg of nickel should be tossed away for obtaining a liter of potable water. In conclusion, first flush diverters are recommended to convert these non-point pollutants to point source. Thus, municipalities can take necessary measures to protect the environment such as using phytoremediation and hyperaccumulator plants in sewages.
显示更多 [+] 显示较少 [-]The Effect of Foliar Application of Different Amino Acids (L-Histidine, Methionine) on Cadmium and Zinc Uptake of Wheat
2022
Özlem Ete Aydemir | Kürşat Korkmaz | Faruk Özkutlu
In this study, the effect of foliar L-Histidine and Methinonin amino acid applications on grain cadmium (Cd) and zinc (Zn) uptake on durum wheat grown in soil contaminated with Cd was investigated. The research was carried out according to the randomized blocks design as a pot experiment in greenhouse conditions. In the experiment, Cd doses were applied as control (0 mg Cd kg-1) and (3 mg Cd kg-1). L-Histidine and Methionine amino acids were applied 7 times from the leaf after the start of flag leaf formation in wheat at 0.5 mM doses and harvested after the grain maturity was completed. According to the results obtained, the wheat grain dry matter yield in 3 mg Cd kg-1 polluted soil was 44.5 mg grain-1 in the control, while the dry matter weight was increased with the application of L-Histidine and Methionine from the leaves being 48 and 50 mg grain-1, respectively. It was determined that there were differences in grain Cd and Zn concentrations with the application of amino acids from the leaves at the dose of 3 mg kg-1 cadmium. When the grain Cd and Zn intakes were compared with the control, it was found that the grain Cd concentration decreased, and the Zn concentration increased as a result of the application of amino acids. The high amount of Cd in wheat can make it to the human body through the food chain and is known to cause serious health problems after a certain amount of accumulation. As a result of this study, it is seen that L-Histidine and Methionine are effective in reducing Cd in the grain, and these amino acids probably form a complex with Cd, resulting in less transport.
显示更多 [+] 显示较少 [-]Determination of Heavy Metals in Locally Available Chocolates in Lahore Region
2021
Muhammad Amjad | Shabbir Hussain | Zia Ur Rehman Baloch | Aoun Raza
Heavy metal toxicity can either be acute or chronic effects. Long-term exposure of the body to heavy metal can progressively lead to muscular, physical and neurological degenerative process. In this research, a total of 30 representative chocolate samples were collected from local shops and markets in Lahore. All the samples were analysed to assess the levels of Lead (Pb), Nickel (Ni), Chromium (Cr) and Cadmium (Cd) by using Atomic Absorption Spectrophotometer in Pakistan Council of Scientific and Industrial Research (PCSIR), Lahore. It was observed that the majority of chocolate samples contain heavy metals levels higher than the permissible limits as recommended by Punjab Food Rules (PFR) 2011. The levels of Pb ranged between 0.375 and 3.4 mg/kg with 90% samples having concentrations exceeding PFR allowable limit (0.5 mg/kg). Whereas, Ni concentrations varied from 0.005 to 0.28 mg/kg and 80% samples were above the PFR limit (0.025 mg/kg). Further, Cr levels analysed between 0.005 to 0.28 mg/kg and 53% samples had Cr concentrations higher than PFR limit (0.02 mg/kg). Similarly, Cd levels were observed between 0.50-3.25 mg/kg with 53% samples having Cd concentrations exceeding the PFR limit (1.0 mg/kg). Investigation indicates that the quality of available chocolates is not recommendable for eating because of the higher concentrations of toxic heavy metals.
显示更多 [+] 显示较少 [-]Heavy Metals in Cassava (Manihot esculenta Crantz) Harvested from Farmlands along Highways in Owerri, Nigeria
2020
Josephat Nwabueze Okereke | Judith Nkeiru Nduka | Ukaoma Augustina Adanma | Odangowei Inetiminebi Ogidi
Concentrations of heavy metals (Cu, Pb, Zn, Ni, Cd) in cassava grown on farmlands along highways in Owerri, was investigated. Cassava leaves and root samples were harvested from cassava farms along three major roads with high traffic density and another rural road that served as control location. Standard laboratory procedures to determine the concentration of these metals were adopted using Atomic Absorption Spectrophotometer. The metal concentrations in mg/kg in cassava root showed high levels of Cu (6.29±0.0346), Zn (8.49±2.243), Pb (0.5267±0.3156) and Cd (0.1167±0.0833). The concentrations of the heavy metals in the cassava leaves were of the order: Zn > Cu >Pb> Ni > Cd. Soil plant transfer factor values for all the metals in all the sites indicated medium accumulation. Heavy metal concentrations in soil showed significant correlation with concentrations in cassava root with no significant statistical differences in bioaccumulation of heavy metals in different parts of cassava. The overall results showed evidence of some heavy metal pollution on the soils and cassava plant.
显示更多 [+] 显示较少 [-]Heavy Metal Concentrations in Razor Clam (Solen marginatus, Pulteney, 1799) and Sediments from Izmir Bay, Aegean Sea, Turkey
2019
Elif Çağrı Taş | Uğur Sunlu
This study was carried out to determine the concentrations of some heavy metals (Cd, Cu, Pb, Zn, Cr and Fe) in Solen marginatus (Pulteney, 1799) and sediments in the middle region of Izmir Bay. Metal concentrations in S. marginatus vary in the one-year period between summer 2005 and summer 2006. The order of accumulation of metal concentrates in soft tissue of razor clam was determined as Cd < Pb < Cr< Cu < Zn < Fe. Metal accumulations in the soft tissue of S. marginatus were compared with Provisional Tolerable Weakly Intakes (PTWI) and Provisional Tolerable Daily Intakes (PTDI) for human consumption. The results show that the maximum concentrations of metals were markedly below the limits of the FAO (Food and Agriculture Organization), WHO (World Health Organization) and TFC (Turkish Food Codex) for human consumption. The order of the metal concentrations detected in the sediment samples was Cd < Pb < Cu< Cr < Zn < Fe. In this study, the maximum heavy metal values determined in the sediment are below the criteria values of the stated for international sediment quality guidelines in the NOAA (The National Oceanic and Atmospheric Administration), OMEE (The Ministry of Environment and Energy of Ontario), ANZECC (The Australia and New Zealand Environmental on Conservation Council), CCME (The Canadian Council of Ministers of Environment). There was a statistically significant but weak correlation between concentrations of Cu and Cr in sediment and S. marginatus. The significant correlations have shown that Solen species can be used as a bioindicator species, such as mussels due to their ability to accumulate heavy metals.
显示更多 [+] 显示较少 [-]Impact of Brewery Waste Sludge on Sorghum (Sorghum bicolor L. Moench) Productivity and Soil Fertility in Harari Regional State, Eastern Ethiopia
2017
Nano Alemu Daba | Abduletif Ahmed | Muktar Mohammed
The study was conducted on farmers' field in sofi district of Harari Regional State during 2013/2014 main cropping season, eastern Ethiopia, to investigate the impact of brewery sludge on sorghum production and soil fertility. The treatments comprised seven levels of brewery sludges (0, 2.5, 5.0, 7.5, 10.0, 12.5 and 15.0 t ha-1) and NP inorganic fertilizer at recommended rate, arranged in randomized complete block design with four replications. Application of brewery sludge at 15 t ha-1 significantly increased the yield and biomass yield of sorghum by 79 and 85% over control and by 57 and 67% over NP application, respectively. There was no effect of brewery sludge application on heavy metals concentrations in soil after crop harvest, compared to international standard tolerable level. Co and Se levels were high in the control as well as in the soils treated with brewery sludge indicating the already high concentration of these heavy metals in the soils of the area. Plots, which received higher brewery sludge application, resulted in decreased or less percentage of grain nitrogen content showing the independence of grain protein content on lower brewery sludge level. The nitrogen uptake by sorghum grain, straw and the total was maximum (52.68, 44.25 and 79.03 kg ha-1, respectively) with the application of brewery waste sludge at 10 and 15 t ha-1 which were significantly higher than the other brewery sludge and NP mineral fertilizer applications.
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