Samples of bulk free-fall and roof-intercepted rainwater over five different roof types (iron-zinc corrugated sheets, concrete slate tiles, Adex/asbestos cement sheets, aluminium sheets, and thatch) were collected and analysed using standard methods with adequate quality-control and quality-assurance measures. The mean values of some of the investigated parameters for the roof-intercepted samples occurred within four continuous sets of ranges, viz: <0.11 mg l −1 (NH + 4 ), 0.11-1.00 mg l −1 (Na. The other parameters were: pH (6.68-7.45), conductivity (19.4-122.6 µS cm −1 ), colour (25.9-257.6 Pt-Co), and turbidity (6.4-24.7 NTU). The corresponding mean values for the free-fall samples were either within the low end of the same range or about one order of magnitude less than that of the roof-intercepted samples. The enrichment factors of the roof-intercepted samples were within the range of 1.03-4.92 with an overall mean of 2.9 ± 0.3 standard error. Most of the water-quality parameters, including bacterial counts and the number of isolated species were higher both at the beginning and end of the rainy season (when both dry and wet depositions were high) than during the mid-season period (when only wet deposition was high). They also showed an increase with the age of roof materials, especially the samples over Adex and concrete slate roofs. The rainwater sources were not potable without necessary treatment but suitable for a wide range of other applications.

Citrus sinensis seed and peel oils were extracted by solvent extraction using n-hexane, after air drying and grinding. Soaps were formed by saponification methods. Fatty acid composition of the oil samples were analyzed using Gas Chromatograph-Flame Ionization Detector (GC-FID). Physicochemical properties of the oils and soaps were determined following standard methods. Antimicrobial activities were assessed by the agar disc and hole-in plate methods. The seed and peel oil yield were 38 and 30%, respectively and the colors were golden yellow and brownish-yellow, respectively. Physicochemical properties of the oil samples determined were: refractive index (

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In this study, dumpsite soils and vegetables were analyzed for total elemental composition using a 5SDH Tandem Pelletron accelerator available at Centre for Energy Research and Development, Obafemi Awolowo University Ile-Ife. The results at a 2.5 MeV energy revealed the presence of elements: Cu, Cr,

Abstract. Gold 1 N. A total of 51 stream water and sediment samples were randomly collected from water sources available to the communities. Stream water samples collected were analyzed for heavy metals using atomic absorption spectrophotometer (AAS) while associated stream sediments were analyzed with x-ray fluorescence spectrometer (XRF). Heavy metals analyzed in both sample types include As, Cu, Cd, Pb, Fe, Cr, Mn, Zn, Zr, and Sr. Results obtained showed the stream waters to be richly concentrated with toxic metals in the range of As(0.002± 0.001 to 0.004± 0.001 mg/l), Cd (0.003±0.001 to 0.034± 0.004 mg/l), Pb (0.002± 0.001 to 0.017±0.003mg/l), Cu(0.078±0.003 to 2.326±0.004 mg/l), Zn(0.013 ±0.004 to 1.937±0.015mg/l), Fe (0.013±0.005 to 0.825±0.085mg/l), Mn (0.002±0.001 to 0.016±0.001mg/l) and Cr (0.009 ± 0.002 to 0.069 ± 0.031mg/l). The variation of heavy metals in stream water samples are Cu>Zn>Cr>Fe>Cd>As>Pb>Mn. Similar contamination of the stream sediments were observed as XRF results showed the sediments to have high concentration of heavy metals As, Cd, Pb ,Cu and Cd clearly above regulated limits. Enrichment Factor of the elements obtained showed high contamination of both the stream water and sediments with toxic metals as a result of high illegal gold mining operations in the area under study.