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Browsing Research Articles by Subject "Clarius werneri"

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    1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its derivatives in marketed Clarius werneri caught from Uganda’s major urban wetlands
    (Journal of Toxicology and Environmental Health Sciences, 2014-07-29) Nnamuyomba, Proscovia; Jolocam Mbabazi; Muhammad Ntale
    The presence of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and derivatives in the Clarius werneri of Uganda’s major urban wetland ecosystems was investigated. Solid dispersion extraction method for extraction, florisil column method for clean-up, gas chromatograph equipped with an electron capture detector (GC-ECD) for analysis and gas chromatograph equipped with mass spectrophotometer (GC-MS) for confirmation of results were used in this study. The major DDT contaminants detected in the samples were p,p’-DDD, p,p’-DDE and p,p’-DDT which were found in 25, 22 and 21% of the samples, respectively. o,p’-DDD was detected in 19% and o,p’-DDT in 13% of the samples. For o,p’-DDE there were no measurable values since the levels were below limit of quantitation (LOQ). The concentrations of DDT derivatives ranged between ND-0.478 µg/kg for p,p’-DDE, ND-0.387 µg/kg for o,p’-DDD, ND-0.476 µg/kg for p,p’-DDD, ND-0.345 µg/kg o,p’-DDT and ND-0.556 µg/kg for p,p’- DDT. The concentration of total DDT in C. werneri was in the range of 1.111 to 1.328 µg/kg dry wt. Generally, all the samples had DDT derivative levels below the maximum residue limit recommended by Food and Agriculture Organisation/World Health Organization (FAO/WHO) Codex Alimentarius Commission.
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    Trace Elements in Marketed Rastreneobola Argentea and Clarias Werneri Caught from Selected Aquatic Ecosystems in Uganda
    (International Journal of Current Trends in Engineering & Technology, 2015-08) Nnamuyomba, Proscovia; Mbabazi, Jolocam; Ntale, Muhammad
    Samples of two fish species Rastreneobola argentea and Clarias werneri from Lake Victoria, Lake Kyoga and Nakivubo and Lubigi wetlands were analysed for Cu, Zn, Pb and Cd using an Atomic Absorption Spectrophotometer - Perkin-Elmer Model 2380. The results revealed that Zn concentrations were the highest in both species, followed by Cu; Pb and Cd being the lowest. The concentrations of Cu, Zn, Pb and Cd in R. argentea from Lake Victoria ranged between 20.5- 115 µg/Kg, 175 - 495 µg/kg, 15 - 77.5 µg/Kg and 2.5 - 4.45 µg/kg respectively, mean while their concentrations in the same fish species from Lake Kyoga ranged between 12.5 - 37.5 µg/kg (Cu), 35-100 µg/kg (Zn), 5-12.5 µg/kg (Pb), 0.5-1.5 µg/kg (Cd) dry weight. In C.werneri, heavy metals varied between 197-337.5 µg/kg (Cu), 235-670 µg/kg (Zn), 60-77.5 µg/kg (Pb) and 2.5-6.98 µg/kg (Cd) in Lubigi wetland and in Nakivubo wetland, concentrations of heavy metals ranged between 7521320 µg/kg for Cu, 1230-1437 µg/kg for Zn, 85-97.5 µg/kg for Pb and 2.2-7.75 µg/kg for Cd. Heavy metal concentrations obtained in this study were below permissible limits issued by WHO/FAO. Therefore, the consumption of these fish species may not pose any threat to human health. However periodic monitoring of these metals in the fish caught from water bodies located in urban areas is highly essential to public health