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Olushola S. Ayanda Olalekan S. Fatoki Folahan A. Adekola Bhekumusa J. Ximba 《Environmental science and pollution research international》2013,20(11):8172-8181
The removal of triphenyltin chloride from contaminated simulated seawater with adsorption method was discussed. The adsorbents used are fly ash, nSiO2, and nSiO2/fly ash composite. The results showed that the adsorption of the adsorbents increases with increase in the adsorbent dose, contact time, pH, stirring speed, initial TPT concentration, and decreased with increase in temperature. The adsorption fitted well with the Freundlich isotherm, showing that the adsorbent and TPT combined with function groups and the adsorption kinetics followed the pseudo-second-order kinetic model. The thermodynamic parameters were also evaluated. Optimal conditions for the adsorption of TPT from simulated seawater were applied to TPT removal from natural seawater. A higher removal efficiency of TPT (>99 %) was obtained for the nSiO2/fly ash composite but not for fly ash and nSiO2. 相似文献
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The effect of white African mineral dye Yombofita (YF) on the activities of alkaline phosphatase (ALP), acid phosphatase (ACP) and malondialdehyde (MDA) levels in the skin, liver, kidney and serum of albino rats was investigated. The chemical analysis of the dye was first carried out using solubility test, pH determination and X-ray fluorescence (XRF) elemental analysis. Six different concentrations (0.05, 0.15, 0.25, 0.5, 0.75 and 1.00%) of the dye were prepared using hydrogen peroxide (30 volume) as solvent. A total of 80 albino rats (Rattus norvegicus) were used for the study. The rats were divided into 8 groups of 10 each and were maintained on commercial feed for the period of the experiment i.e. 30 days. In group 1, the control group, the animals were applied distilled water on their heads, whereas in group 2 the vehicle i.e. hydrogen peroxide was applied. In groups 3 to 8 various concentrations of YF (white) dye ranging from 0.05, 0.15, 0.25, 0.5, 0.75 to 1.00% was applied respectively. At the end of the experiment, blood samples were collected and portions of the selected tissues were excised for the determination of ALP and ACP activities. The MDA level was also determined in the skin of experimental animals. The results revealed a significant decrease (p?0.05) with increasing concentration of the dye in the activities of ALP and ACP in the kidney and skin but not in the liver while the level of MDA in the skin increased significantly (p?0.05) with increasing concentration of the dye. 相似文献
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Olalekan S. Fatoki Hussein K. Okoro Folahan A. Adekola Bhekumusa J. Ximba Reinette G. Snyman 《The Environmentalist》2012,32(1):48-57
Heavy metal concentrations in black mussels (Mytilus
galloprovincialis) collected from Cape Town Harbour were determined using energy dispersive X-ray fluorescence (EDXRF) and inductively coupled
plasma-mass spectrometry (ICP-MS). EDXRF showed that tissue portions of the mussels contained K, Ca, Fe, Cu, Zn, Si, Sr, Al
and Au, while the shell portion contained K, Ca, Fe, Cr, Zn, Si and Sr. In addition to these metals, EDXRF also revealed the
presence of Al in the shells of the largest mussels. Highest concentrations of Cu and Zn were recorded in the tissues of the
smallest mussels. Due to poorer detection limits of EDXRF, ultra-trace elements (Mn, Pb, As, Hg, V, Cr, Sn, Cd, Ni and Co)
were determined in mussels using ICP-MS. The average metal concentrations found in the mussels are as follows; Pb (7.30 ± 0.67),
Cd (1.98 ± 0.13), Hg (4.92 ± 0.60), As (6.94 ± 0.04), Sn (2.63 ± 0.13), Ni (1.88 ± 0.05), Cr (3.54 ± 0.05), V (4.17 ± 0.23),
Co (0.74 ± 0.01) and Mn (35.20 ± 1.46). ANOVAs, Pearson correlation and principal component analysis (PCA) were employed in
data analysis. The order of the abundance of metals in the mussels is Mn > Pb > As > Hg > V > Cr > Sn > Cd > Ni > Co. The
average metal concentrations found in the mussels were higher than the permissible Food and Agriculture Organization (FAO)
limits and other international guidelines. 相似文献
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The concentration of some heavy metals (lead, zinc and copper) were determined in the scalp hair of children (1–15 year) and active adults (16–40 year) in two Nigerian cities. The levels of zinc were found to be higher in children than in the adult population. There was a significant difference (P?=?0.05) between the two age groups. The levels of copper were all within the same range for the two age groups and independent of location. The levels of lead were generally higher in adults than in children. However, there was no significant difference (P?=?0.05) in the average concentrations of lead between the children and adult populations of the two cities. The regression analysis indicated a strong correlation (r?=?0.86) between zinc and copper. 相似文献
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Regional Environmental Change - A critical element of current flood management is the importance of engaging key policy actors when policy decisions are to be made. However, there is still only... 相似文献
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Concentrations of some heavy metals in Tilapia zilli (Tilapia) and Synodontis membrane (Catfish), the two common fishes from Asa River Ilorin, Nigeria have been determined. Manganese, zinc, iron, and lead, were present at appreciable concentrations in the tissues of the two species while cadmium, mercury, and nickel, were found to be less than 0.01?ppm. Concentrations of metals were highest downstream than at upstream locations. Mean concentrations of Mn in Tilapia, ranged between 0.56?ppm at the upstream end and 2.69?mg/kg of fresh weight at the downstream end. Pb, Zn, and Cr ranged between 4.05 and 5.59?mg/kg of fresh weight, 0.09 and 1.16?ppm, 5.62 and 11.15?ppm, and 0.09 and 0.13?ppm respectively. In the Catfish, Mn, Fe, Zn, and Cr ranged between 0.62 and 0.78?ppm, 3.79 and 8.79?ppm, 0.78 and 1.57?ppm, 7.30 and 15.15, and 0.23 and 0.35?ppm respectively. Heavy metals except lead did not pose any health risks in human since the calculated probable amounts being ingested by an average adult (50?kg average weight) per day were lower than WHO maximum recommended value of intake. However, the level of lead was higher than WHO limit and this could render inedible the fishes from this catchment river. 相似文献
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A. M. O. Abdul Raheem F. A. Adekola I. O. Obioh 《Environmental Modeling and Assessment》2009,14(4):497-509
A combination of multivariate statistical methods including factor analysis, principal component analysis, principal component
regression, and multiple linear regression (MLR) were employed to evaluate the influence of seasons on the concentrations
of ozone, sulfur (IV) oxide, and oxides of nitrogen in ambient air of Nigerian cities of Lagos and Ilorin. The former city
is located in the coastal area, and it is highly congested with a high intensity of marine, vehicular, and industrial activities,
and the latter city is a medium size town, located in the central guinea savannah zone of Nigeria. Samples were collected
using a high-volume sampler from near the ground at various sites of diverse human and industrial activities, during wet and
dry seasons from 2003 to 2006. The PCA reveals three distinct groupings during the day for all data, which is a reflection
of different factors contributing to the atmospheric chemistry of these cities. The predicted ozone concentration values by
MLR agree fairly well with the measured data. The dependence of ozone on meteorological parameters including relative humidity,
air temperature, and sun exposure and the precursor pollutants depends on weather and the anthropogenic activities. The results
for the two cities indicate that reduction in the level of NO2 is accompanied by an increase in the level of ozone, suggesting the interconversion between the two via photochemical activity. 相似文献
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Chemical and mineralogical characterization of sediments collected from seven different locations along Asa River in Ilorin,
Nigeria have been carried out. The total concentration of Mn, Cr, Fe, Zn and Cu were monitored using Total Reflection X-ray
Fluorescence (TXRF). The range of concentration of these metals were: Mn (179.9–469.4, Fe (1998.4–4420.4) Cr (3.0–11.3), Zn
(26.6–147.6), Cu (1.9-13.3) mg kg−1. The mineralogical composition was determined using X-ray diffraction (XRD) method and this was complemented with the Infrared
Spectroscopy. It was found that the sediments of Asa River had predominantly quartz, and goethite was present in five of the
seven locations. Chromite (FeCr3O4) and pyrite (FeS) were also identified at some locations along the River. Higher enrichment factors were calculated for Zn,
Cr, Mn, and Fe in the sediment indicating anthropogenic source of contamination. Pyrite was prominent at a location receiving
effluent from a detergent industry and near a refuse dumpsite. 相似文献
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