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ஐ.எஸ்.எஸ்.என்: 2380-2391

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தொகுதி 3, பிரச்சினை 1 (2016)

ஆய்வுக் கட்டுரை

Removal of Drugs by Cuttlefish Bone Powder: Equilibrium, Kinetics and Thermodynamic Study

Hassen Khazri, Ibtissem Ghorbel-Abid, Rafik Kalfat and Malika Trabelsi-Ayadi

This study aimed to describe the adsorption of three pharmaceuticals which represents a source of environment contamination. The adsorption of three drugs: ibuprofen (IBU), naproxen (NAP) and carbamazepine (CBZ) from river water onto cuttlefish bone powder (CFPB) as adsorbent material were carried of various parameters such as contact time, the effect of pH, the varying of the concentration and the temperature. Adsorption kinetic data were modeled using the Lagergren first order and the pseudo-second order kinetic equations. The kinetic results of adsorption are described better by using the pseudo-second order model. Freundlich and DR equations provided better compatibility than Langmuir equation. The thermodynamic parameters obtained indicate that the adsorption of pharmaceuticals on the cuttlefish bone powder is a spontaneous and endothermic process

ஆய்வுக் கட்டுரை

Evaluation of Effects of Heavy Metal Contents of Some Common Spices Available in Odo-Ori Market, Iwo, Nigeria

Peter Olusakin O and David Olaoluwa J

This study is aimed at assessing the levels of Fe, Cu, Cd, and Pb in some common spices available in Odo-ori Market, Iwo, Osun State, Nigeria. Four samples each of naturalspices (ginger, garlic, onion and locust beans) and processed spices (curry, thyme, nutmeg and beef spicy) were bought and analysed for Fe, Cu, Cd, and Pb using Atomic Absorption Spectrophotometry. 2 g of each of the samples was digested using 30 mL of concentrated HNO3 and heated until digestion was complete. The digests were filtered into standard 30 mL volumetric flask using Whatmann filter paper and made up to mark with distilled water. The digested samples were analysed for Fe, Cu, Cd, and Pb using Buck Scientific Model 210 VGP Atomic Absorption Spectrophotometer. Results showed that the concentrations of heavy metals, such as Fe, was present at level ranging from 33.4 mg/kg – 107 mg/kg and Cu, was present at level ranging from 4.35 mg/kg - 8.40 mg/kg in natural spices. Cd was above the permissible limit set by WHO (0.30 mg/kg). The Fe and Cu levels in natural spices were below maximum permissible limit set by WHO while Cd was above the permissible limit. Therefore, it can be concluded that majority of these spices were not contaminated with the studied heavy metals except Cd which was present in natural and processed spices above MPL and indicating Cd pollution in the natural and processed spices. To avoid chronic effect (which involved accumulation of the metals in the body system and which can be harmful to human health), too much of the spices (processed) and continuing/routine use should be avoided.

ஆய்வுக் கட்டுரை

Elemental Analysis of Nutrients in Dairy Manure by Automated X-ray Fluorescence Spectrometry

Aicardo Roa-Espinosa, John L Markley, Trang T Vu, Evgeny Filatov and Samuel W Roa-Lauby

We have determined that X-ray fluorescence (XRF) spectrometry can be used as a rapid and precise method for quantitative elemental analysis of macro and micro nutrients in dairy manure. The elements chosen for this study were N, P, K, Ca, Mg, S, Zn, Mn, Fe, Cu, Al, Na, B, and C. The wavelength-dispersive XRF spectrometer was calibrated by comparing its results with a panel of dried dairy manure samples with analyses from inductively coupled plasma (ICP) obtained from three independent certified laboratories. In addition, the XRF results for C, N, and S were compared with those from a high-temperature combustion (HTC) analyzer dedicated to measurements of these three elements. Then the performance of the calibrated XRF was tested against a separate panel of dairy manure samples collected at fifteen different sampling points at a manure processing plant. Subsamples from these samples were analyzed for the 14 elements of interest by a certified laboratory. The close agreement between the XRF results and those of the certified laboratory established that XRF can be used as a simple and precise method for the elemental analysis of dairy manure

ஆய்வுக் கட்டுரை

Identification, Mechanisms and Kinetics of Macrolide Degradation Product Formation under Controlled Environmental Conditions

Igal Gozlan, Ilana Koren and Dror Avisar

Erythromycin, azithromycin, clarithromycin and roxithromycin are antibiotics belonging to the widely used macrolide group. Their presence in the environment has been much investigated, despite the rapid degradation of Erythromycin to its spiroketal degradation product. In this study, the formation of macrolide degradation products was investigated in various aqueous solutions, each containing 100 μg/mL of the respective macrolide, under controlled artificial conditions: three phosphate buffer solutions (pH 5, pH 7 and pH 8.5), and a buffer solution at pH 7 with the addition of humic acids. Two solutions from natural sources were also examined: secondary effluent and tap water. The obtained degradation products were identified by their HRMS and NMR spectra (for Erythromycin-spiroketal, obtained from pure compounds isolated by preparative HPLC) as: N-oxide, N-desmethyl and N-didesmethyl forms of all examined macrolides. These degradation products were obtained only under irradiation by sunlight, while the Erythromycin-H2O degradation products were also obtained in the shade. The secondary effluent was the most significant medium for achieving macrolide degradation products. According the degradation product’s t1/2 values obtained in the secondary effluent, the azithromycin was most rapidly degraded (23 hours). Furthermore, results suggested that the degradation process was activated by sunlight irradiation energy, and that the degradation mechanism started with the transfer of an electron from the amine group to O2 to produce the radical ions RMe2N·+ and O2 ·- as intermediates and production of the N-oxide and N-desmethyl macrolide degradation products. The kinetics of macrolide degradation was calculated as a first-order reaction.

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Seasonal Variation of the Physicochemical and Bacteriological Quality of Water from Five Rural Catchment Areas of Lake Victoria Basin in Kenya

Ouma SO, Ngeranwa JN, Juma KK and Mburu DN

Seasonal and regional variation of the physicochemical and bacteriological characteristics of 180 water samples collected from five fish landing beaches of Luanda Rombo, Dunga, Marengo, Osieko and Usoma in the Lake Victoria Basin of Kenya was investigated. Colour, chloride, TSS, TDS, zinc, mercury and nitrates were all below the maximum permissible but other parameters were above limits. Pathogenic bacteria isolated were Escherichea coli (69.6%), Salmonella spp (18.5%), Shigella spp (6.5%) and Vibrio cholerae (5.4%). Dunga site was the most polluted and that water from catchment areas closer to urban areas was more contaminated. Seasonal variation showed that pH, colour, turbidity, TSS, BOD, phosphate, nitrates and coliforms were significantly high (p<0.001) in the wet season. In the dry season temperature, EC, TDS, heavy metals, chloride and ammonia were significantly high (p<0.001). The high level of pollutants in wet season was due to storm water run offs carrying a higher load of contaminants while in dry season it is likely due to the increased solubility of ions as a consequence of the elevated water temperature and low pH. High loads of contaminants in water could pose immediate and long term public health concerns to unsuspecting water users especially due to the pathogenic coliforms, nutrients, algae and heavy metals. Therefore, proper policies regarding protection of the Lake Victoria environmental integrity are required and stiff measures should be taken to discourage law breakers.

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