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Despite recording the worst heavy metal disaster involving children, there is still scarcity of information on risk assessment of playground soils in Nigeria. In this study, thirty-six soil samples at 0-5 cm depth were collected from nine playgrounds in Owerri metropolis during the dry and rainy seasons. Five heavy metals were fractionated into six chemical fractions using a modified sequential extraction scheme and mean concentrations quantified by AAnalyst 400 Perkin Elmer AAS. Predictive risk models were used to obtain information about the risk of metals contamination to children using these playgrounds for longer periods. These reveal that there were no significant differences in the mean values of bioconcentration factors of all five metals in the various playgrounds for the two years of data. Even though risk values for both dry and rainy season followed the same trend, it was observed that the Zinc showed highest bioconcentration factors (1.6), average daily dose (230.08 mg/kg/day) and risk (5095593 mg/kg/6years). Over all, playgrounds UPS, TSO and SCP had highest mean risk values, respectively. Though with no clear trend, mobility factors showed a weak and positive correlation with risk. Children in playgrounds of public schools within Owerri metropolis could, therefore, be at risk of Mn, Cu and Zn toxicity problems as projected risk values were high for all studied playgrounds. This assessment could help identify playgrounds with urgent need for heavy metals reduction goals, consequently contributing to preserving children’s health.
This study assesses the physiochemical characteristics and heavy metals content of crude oil polluted soils and non-polluted soils from Ohaji/Egbema, Imo State. Soil samples were collected at depths of 0-30 cm at each sampling point and then analyzed using standard analytical methods. Data from the five areas were compared to standards for soils in Nigeria and in World Health Organization (WHO) data banks. The results obtained from the analysis showed an average pH of (4.88 ± 0.02 to 5.02 ± 0.04) for polluted soil and (6.57 ± 0.05 to 6.82 ± 0.03) for non-polluted soil, electrical conductivity (571 ± 1.1 to 592 ± 0.8 µS/cm) for oil polluted soil and (383 ± 0.5 to 415 ± 1.6 µS/cm) for non-polluted samples, moisture content (5.2 ± 0.2 to 9.1 ±0.1 %) for polluted soil and (4.5 ± 0.1 to 4.7 ± 0.3 %) for non-polluted soil samples. There was no significant difference in temperature and organic matter for both the polluted and non-polluted soil samples. The heavy metals analysis results showed Fe3+ (0.615 to 0.989 ppm) for oil-polluted soil samples and (0.0453 to 0.273 ppm) for nonpolluted soil samples, Pb2+ (0.017 to 0.180 ppm) for oil-polluted soil and (0.008 to 0.010 ppm) for non-polluted soil. The study reveals that areas that are polluted need urgent remediation if the soil is to be used for agricultural purposes.
With increasing population and human activities, dumpsites experience diverse sources of waste with potential radiation hazards. Ionizing radiations have often been overlooked amongst researchers in third world countries, hence, information in this regard is lacking. In this study, nine dumpsites within Imo State University (IMSU) grounds were assessed for radiation levels using Geiger Muller counter Tube Mullard type ZP 1481 with assisted scalar and stopwatch. After calibration, the instrument was placed one meter above ground level and count rates recorded at 10 minutes interval for each location once in the morning, the afternoon and the evening for seven days. Results reveal higher dose equivalents in some morning periods than in the afternoon and evening. Site ETF2 had highest value of 0.69±0.08 mSv·yr-1, while Extension gate had lowest value of 0.56±0.01 mSv·yr-1. Compared to National Council for Radiation Protection maximum permissible level, these values are quite low. In conclusion, ionizing radiations levels at the studied dumpsites in Imo State University grounds are low and may not pose a threat to persons within the university.
Water Quality index indicating the water quality in terms of index number, offers a useful representation of overall quality of water for public or for any intended use, as well as in pollution abatement programmes and in water quality management. The present study was carried out to determine the Water Quality Index (WQI) of selected rivers in Warri, Delta State, using fourteen physicochemical parameters and on the basis of weighted Arithmetic Index in order to access the suitability of this water for consumption, recreation and other purposes. The parameters were measured monthly for one year at the six selected water bodies. In this study, WQI was determined by the analysis-on the basis of various physicochemical parameters such as pH, chlorides, electrical conductivity, dissolved oxygen, biochemical oxygen demand, total dissolved solid, total suspended solids, chlorides, sulphates, chemical oxygen demand, oil/grease. Result obtained for the different sampling sites were found to fall within the WQI classifications - poor water (100-200) to unsuitable water or unfit (>300). There is, therefore, the need to periodically assess these water bodies to ensure the quality is suitable for the intended purpose.
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