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Volume 4, Emitir 2 (2017)

Artigo de Pesquisa

Recent Influences of Anthropogenic Activities and Seasons on Heavy Metal Distribution in Shoreline Sediments in Lake Victoria Near Kisumu City, Kenya

Francis M Kiema, Philip O Owuor, Raphael JA Kapiyo

The Winam Gulf on Lake Victoria around Kisumu city has seen increase in anthropogenic activities. The activities discharge pollutants, especially heavy metals into the lake. The heavy metals sink into sediments, which slowly release them into the lake water. The objective of this study was to evaluate the distribution and sources of heavy metals into Winam Gulf sediments near Kisumu city during wet and dry seasons. Sediments were sampled from sites at Molasses Plant, Coca-Cola Plant, Rivers Kisat and Kisian discharge points at intervals of 50 m from the shoreline into the lake. The metal level (μg/g) ranges obtained were: 0.90-1.20 (Cd), 2.60-36.00 (Cr), 71.40-122.90 (Cu), 1283.40-1468.70 (Fe), 792.30-1631.20 (Mn), 61.80-181.00 (Pb) and 100.10-187.60 (Zn) with River Kisat discharge point recording the highest levels for all metals. The metal levels were different (p ≤ 0.05) in all sites. River Kisat discharge point had the highest heavy metals concentration due to the dense anthropogenic activities within the adjacent environment. Metal levels varied (p ≤ 0.05) with seasons in all sites with higher levels recorded during wet season an indication of surface runoff. In all sites, the levels decreased (p ≤ 0.05) with increased distances from the shore into the lake suggesting a dilution effect. The results confirm that the anthropogenic activities cause metal pollution. It is necessary to control activities that discharge heavy metals into the lake water and continuously monitor the heavy metal levels. This will enable enforcement agencies to formulate regulations to safeguard human and aquatic life within the gulf.

Artigo de Pesquisa

Boron Waste Concentration Using Shaking Table

Mahdi Haghani

The most important Iranian boron reserves are in the basin of GHEZEL-OUZAN, a river in the West and Northwest area of Zanjan. The majority of these mines have been extracted with a non-advanced way. There are many great waste damps next to the mines which are a threat to the environment for releasing boric acid and because of an average grade of Boron are valuable from financial point as well. Present paper studies possibility of concentration a low-grade boron waste from Moshampa boron mine using shaking table. In order to concentration, 6 factors in 5 levels were considered. The factors included: particle size, water flow rate, frequency, liberation range, tilt angle and feed rate. Optimization was carried out by classic method (one factor at the time). As a result, optimum condition obtained under particle size of +1.18 -2 mm, water flow rate of 3.5 lit/min, frequency of 320 cycle/min, liberation range of 15 mm, tilt angle of 8 degrees and feed rate of 250 g/min. This test yielded 58.43% of B2O3 recovery under optimum conditions performance, and a concentrate with 26.45% B2O3 was produced.

Artigo de Pesquisa

Determination of 2-Isopropoxyphenyl Methyl Carbamate-Propoxur in Roach Control Peanut Butter by High Performance Liquid Chromatography

Yildiz Y, Jan A, Yildiz B

A method for the determination of 2-isopropoxyphenyl methylcarbamate, also known as Propoxur, in pesticides was developed for liquid chromatography equipped with a UV detector. Roach peanut butter sample was prepared with soxhlet extraction ten times; the standard solutions were prepared with n-butyrophenone and methanol as an internal standard, and both isopropoxyphenol (IPP) and 2-isopropoxyphenyl methylcarbamate (propoxur) as control standards. The target compound propoxur was well-separated and showed no interferences in the chromatograms. Propoxur was determined to comprise less than 2% of the sample.

Artigo de Pesquisa

Variations in Nitrogen (NH4+, NO2-, NO3-) and Heavy Metal (Al and Cu)Levels of Water from Swimming Pools in the City Center and Districts of Canakkale, Turkey

Tolga Uysal, Selehattin Yilmaz, Muhammet Turkoglu, Murat Sadikoglu

In this study, some nitrogen (NO2-, NO3-, NH4+) and metal (Al and Cu) concentrations were analyzed during the summer period by using an ultraviolet-visible (UV-VIS) spectroscopy method in a total of 44 swimming pools located in the province and districts of Canakkale (Turkey). Merck Kits equivalent to EPA, APHA, ISO and DIN standards were used for spectrometric analyses. The monthly quality parameter results in this study were evaluated according to various limit standard values for different countries. As a result, NH4+, NO2-, NO3-, Al and Cu concentrations varied between 0.003 and 0.999 mg L-1 (0.073 ± 0.139 mg L-1), 0.042 and 0.277 mg L-1 (0.086 ± 0.039 mg L-1), 0.054 and 76.844 mg L-1 (12.111 ± 10.487), 0 and 0.652 mg L-1 (0.141 ± 0.068 mg L-1) and 0 and 2.216 mg L-1 (0.139 ± 0.163 mg L-1), respectively. Although all the maximum values, except for NO2-, exceeded the limit values of the Turkish Health Ministry (THM), all the average values were under the limit values of THM.

Artigo de Pesquisa

Chemical Characterization of Atmospheric Particulate Matter for K, Cu, Ni and Zn Metals Collected from Agricultural, Semi-Urban and Commercial Locations in NW India

Nirankar Singh, Susheel Mittal, Amit Awasthi, Ravinder Agarwal, Prabhat K Gupta

Atmospheric particulate samples (comprising ≤ 100 micron size particles) were collected from different locations in Patiala, India during 2006-2007 covering rural, agricultural, urban, semi-urban, residential and commercial areas. These samples were analysed to measure the concentration of potassium, copper, nickel and zinc metals by using atomic absorption spectrophotometer and flame photometer. Average monthly concentration of particulate matter varied between 100 ± 30 μgm-3-593 ± 181 μgm-3 during the study period with higher levels in the month of April-May during summers and October-November. Around 80% samples were loaded with SPM>200 μgm-3. Concentration of Cu, Ni and Zn varied between 0.05 μgm-3 -1.45 μgm-3 while K concentration levels varied between 4.5 μgm-3 -20.2 μgm-3 with 60% samples having concentration>10 μgm-3. Monthly averaged SPM concentration levels were compared with the levels of selected metals. Results indicated significant spatial variation in the ambient air levels of SPM, Cu, Ni, Zn and K.

Artigo de Pesquisa

Prevalence of Some Heavy Metals in Mango and Pawpaw Found in Dumpsites of Obio/Akpo and Eleme Local Government Areas in River State, Nigeria

Kpee F, Edori OS

Concentrations of six heavy metals Pb, Cd, Zn, Mn, Cu, and Mg were investigated in dumpsites and non-dumpsites in parts of Rivers State. Similar sizes of two species of fruits mango (Mangifera indica) and pawpaw (Carica papaya) grown at these sites were used for the study. The levels of heavy metals were also investigated in the topsoil at each site. The samples were prepared and digested with mixture of mineral acids HClO4, HCl, H2SO4 and HNO3. They were analyzed by Atomic Absorption Spectrophotometer model 204. The results obtained in mg/Kg showed that heavy metals in mango occurred in the range; Pb (1.34-2.74), Cd (ND - 0.001), Zn (1.09-2.45), Mn (110-178), Cu (2.3-5.20), Mg (0.31-1.73). In paw paw the following were obtained Pb (1.24-1.57), Cd (ND -0.001), Zn (3.84-6.32), Mn (111-115), Cu (2.5-4.11), Mg (1.04-1.84) and in the top soil samples Pb (142-3.66), Cd (ND-0.001), Zn (5.27-8.63), Mn (106-179), Cu (1.24-6.84) and Mg (1.35-1.72). The results revealed that elevated concentrations of heavy metals were obtained in samples from dumpsites when compared to non-dumpsites. The results showed that samples from dumpsites will not be toxic to humans if consumed, as the levels of metals obtained were within standard set by WHO/FAO for daily intake of minerals except for Mn and Pb.

Artigo de Pesquisa

Phytoremediation: An Environmental Friendly Technique - A Review

Rohma Razzaq

Phytoremediation technology is a cost effective and environmentally and ecologically friendly as it utilizes plants natural ability to suck the pollutant present in the soil. There are many plants having this natural ability to up take the heavy metals and organic pollutants from air, soil and water. There are different subsets of phytoremediation; the most effectively used ones are (a) phytofiltration (b) phytoextraction (c) phytostabilization (d) phytovolatilization. In the present review, current knowledge about the phytoremediation and its techniques are discussed.

Artigo de Pesquisa

Assessment of Physicochemical Parameters of Soils from Selected Abattoirs in Port Harcourt, Rivers State, Nigeria

Edori OS, Iyama WA

Pollution arising from anthropogenic activities is a common phenomenon. Soil samples collected from three abattoirs in Port Harcourt (Agip, Iwofe, and Mile III) between the months of January to July. The samples were analyzed for physicochemical parameters after following laboratory procedures, using the appropriate probes. It was observed that the pH of the soils was acidic, ranging from 4.59 ± 0.03–4.99 ± 0.14, electrical conductivity ranged from 208.00 ± 11.21- 404.34 ± 7.18 μS/cm, temperature from 33.14 ± 1.29 -35.04 ± 0.96°C while salinity had a range of 27.531.91-58.65 ± 2.25. The textural class was sandy-clay-loam, implying that the soil contains sand in a higher proportion. Total moisture content was within the range of 16.66 ± 1.73 -21.07 ± 2.05 %, chloride content ranged from 17.10 ± 1.61-31.75 ± 2.00 % whereas total nitrogen and nitrogen based parameters were generally very low in concentration in the soil. Extractable phosphorus content in the soil ranged from 0.66 ± 0.03-1.34 ± 0.33 %, total organic carbon ranged from 12.81 ± 0.15- 16.41 ± 0.49 %, and total organic matter ranged from 22.33 ± 0.86-29.58 ± 0.72 mg/Kg. Total hydrocarbon content ranged between 11.85 ± 0.48 and 27.12 ± 0.48 mg/Kg. The observed result indicated that human activities within the abattoir have influenced the physicochemical speciation of the abattoirs. The high content of the organic components of the abattoir can serve as useful manure for cultivation of plants. However, constant check on the activities at the abattoirs should be put in place to avoid pollution of the environment.

Artigo de Pesquisa

Ultrasonication Extraction - HPLC-VIS Fluorescence Method Validation for Trace Analysis of Oil and Grease in Water

Mohammed Khaled Elbadawy Babikir

A new method was developed to determine the oil and grease in water by HPLC-Vis fluorescence technique. Ultrasonication liquid-liquid extraction method was applied by using 1 ml of toluene to 100 ml of water. The analysis was carried out on a LC-10AT-VP chromatograph with a fluorescence RF. 10 a syknm detector equipped with a varian CN (250 × 4.6 μm) Column. The separation was preformed isocratically using a mixture of 90% solvent (n-Hexane) with 10% solvent (Toluene). Asphaltenic compounds were established to be the main fluorescence chromophores (excitation wave length at 420 nm and emission wave length at 500 nm). The correlation coefficient was (0.992), recovery ranged from 92% to 108% and the limit of detection was found to be 0.06 μg.L-1. The method can be utilized successfully for determination of oil and grease in water samples.

Artigo de Pesquisa

Study on the Interaction of Retinoic Acids to Human Serum Albumin by Fluorescence and Circular Dichroism Spectroscopy

Heyong Huang, Xiansheng Liu, Ruiming Han, Guoxiang Wang

Retinoic acids (RAs) are considered to be endocrine disruptor chemicals and toxic environmental priority pollutants. In this paper, the interactions between RAs and human serum albumin (HSA) were examined by steady state fluorescence, time-resolved fluorescence and circular dichroism spectroscopy (CD). The RAs quenched the fluorescence of the protein remarkably and the mechanism of quenching was found to be static in nature. Synchronous fluorescence studies suggested that the polarity around the tryptophan(Trp) residues and tyrosine(Tyr) residues was not altered in the presence of RAs. The thermodynamic parameters of the binding reactions (ΔGθ, ΔHθ, ΔSθ) were measured,and they indicated the presences of hydrophobic forces and hydrogen interactions in the RAs–HSA interactions. The alterations of HSA secondary structure in the presence of RAs were confirmed by CD and time resolved fluorescence spectroscopy.

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