Browsing by Author "Tyokumbu,E.T"

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    Assessment of arsenic and selenium in cyprinus carpio from alaro stream in Ibadan, Nigeria
    (2014) Tyokumbu,E.T; Okorie,T.
    An assessment was carried out on the concentration of arsenic (As) and selenium (Se) in the organs of Cyprinus carpio from Alaro stream in Ibadan, Nigeria. A total of 32 fish were collected from the sampling of Alaro stream from June to December 2003 and preserved by freezing. Dissections were carried out using dissecting set in order to remove the gills, fins, gut (intestine), liver, bones and muscle. Acid digestion was carried out after drying and pulverization of the fish organs. Inductively coupled plasma-mass spectrometer (ICP-MS) was used for the trace metal analyses while bovine liver standard reference material (SRM) from the National Institute of Standards (NIST) was used for quality assurance of the results. The range of the As in the organs of C.carpio was 0.000- 0.963ppm, while the following increasing order of mean concentration: fins
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    Assessment of heavy metals in the fish mormyrus deliciousus and heterobranchus longifilis from alaro Stream in Ibadan, Nigeria
    (2014) Tyokumbu,E.T; Okorie,T.
    study was carried out on the assessment of heavy and trace metals in the tissues of two fish species, Mormyrus deliciousus and Heterobranchus longifilis in Alaro stream ecosystem in Ibadan, Nigeria. Cast nets with mesh sizes ranging between 30- 50 mm with varying dimensional sizes were used for catching the two fish species over 3-month duration. Sixty-seven fishes were caught in the sampling with M. deliciousus making up 27 of the total while H. longifilis was 40 over 3-month duration. Fish dissections (M. deliciousus: n=27; H. longifilis:n=40) were carried out using dissecting set to remove the gills, gut, liver, fins and muscle which were oven dried at 1050C for 6 hours. Pulverized tissues and organs were acid-digested for heavy and trace metal analyses using the inductively coupled plasma-mass spectrometer (ICP-MS). Percentage recoveries from the reference material were all above 70% with a range of 75. 25% (Pb) to 104. 54% (Ag). Mean of some heavy and trace metals were comparatively higher in M. deliciousus: Mg(10082ppm, fins), Co(8. 56ppm, muscle), Cu(175. 78ppm, liver), Zn(275. 2ppm, muscle), As(0. 963ppm, muscle), Se(11. 80ppm, liver), Mo(1. 73ppm, liver) and Pb(14. 12ppm, liver) while Na(12980ppm, bone), K(30912ppm, liver), Ca(203189ppm, bone), V(12. 98ppm, liver), Mn(752. 9ppm, liver), Fe(10092. 0ppm, liver), Cd(3. 208ppm, liver) were higher in H. longifilis whereas the following trace metals were the same for both species of fish: Nickel, Ni (5. 82ppm) and Silver, Ag (2. 33ppm). Most of the heavy metals were high due to their physiological requirement in the tissues of the fish species. As, Ag, Cd and Pb exceeded the recommended limits set by the World Health Organization for most of the tissues and organs in M. deliciousus and H. longifilis. This shows that these fish species caught in Alaro stream ecosystem are not safe for human consumption
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    Assessment of heavy metals in the fish mormyrus deliciousus and heterobranchus longifilis from alaro Stream in Ibadan, Nigeria
    (2014) Tyokumbu,E.T; Okorie,T.
    study was carried out on the assessment of heavy and trace metals in the tissues of two fish species, Mormyrus deliciousus and Heterobranchus longifilis in Alaro stream ecosystem in Ibadan, Nigeria. Cast nets with mesh sizes ranging between 30- 50 mm with varying dimensional sizes were used for catching the two fish species over 3-month duration. Sixty-seven fishes were caught in the sampling with M. deliciousus making up 27 of the total while H. longifilis was 40 over 3-month duration. Fish dissections (M. deliciousus: n=27; H. longifilis:n=40) were carried out using dissecting set to remove the gills, gut, liver, fins and muscle which were oven dried at 1050C for 6 hours. Pulverized tissues and organs were acid-digested for heavy and trace metal analyses using the inductively coupled plasma-mass spectrometer (ICP-MS). Percentage recoveries from the reference material were all above 70% with a range of 75. 25% (Pb) to 104. 54% (Ag). Mean of some heavy and trace metals were comparatively higher in M. deliciousus: Mg(10082ppm, fins), Co(8. 56ppm, muscle), Cu(175. 78ppm, liver), Zn(275. 2ppm, muscle), As(0. 963ppm, muscle), Se(11. 80ppm, liver), Mo(1. 73ppm, liver) and Pb(14. 12ppm, liver) while Na(12980ppm, bone), K(30912ppm, liver), Ca(203189ppm, bone), V(12. 98ppm, liver), Mn(752. 9ppm, liver), Fe(10092. 0ppm, liver), Cd(3. 208ppm, liver) were higher in H. longifilis whereas the following trace metals were the same for both species of fish: Nickel, Ni (5. 82ppm) and Silver, Ag (2. 33ppm). Most of the heavy metals were high due to their physiological requirement in the tissues of the fish species. As, Ag, Cd and Pb exceeded the recommended limits set by the World Health Organization for most of the tissues and organs in M. deliciousus and H. longifilis. This shows that these fish species caught in Alaro stream ecosystem are not safe for human consumption
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    Assessment of physico-chemical parameters and cyclopoid copepod abundance in awba Reservoir, Ibadan
    (2014) Tyokumbu,E.T
    A study was carried out on the effects of physico-chemical parameters on the microscopic cyclopoid copepod abundance in Awba reservoir, University of Ibadan between January and February 2005.McMaster Microscope was used to observe and identify the copepods while a water quality test kit was used to assess the physico- chemical parameters. The results showed a variation in the physico-chemical parameters of the sites with ranges for dissolved oxygen: 21.2mg/l ± 0.85 to 24 mg/l ± 1.71, biochemical oxygen demand (BOD): 10.3 mg/l ±0.57 to 11.2 mg/l ±1.4. Temperature 28.10C±0.23 to 300C ±2.07, pH 7.2±0.13 to 7.5±0.27 and conductivity 304 µS/cm ± 42.7 to 330.5 µS/cm ± 70.3. Diverse taxonomic groups of cyclops were encountered at the four study sites in Awba Reservoir during the sampling period. The dominant groups varied across the sites. For site 1, Tropocyclops mellonbyi was dominant with a Berger-Parker Diversity Index (BPDI) of 92%, for site 2, Tropocyclops mellonbyi, Halicyclops korodiensis; Thermocyclops iwogiensis were present with a BPDI of 72%, 16% and 12%, respectively. For site 3, Tropocyclops mellonbyi and Halicyclops korodiensis were encountered with a BPDI of 88% and 12% for site 4, Ectocyclops ilariensis had a BPDI of 100% as the only cyclop species. The number of taxonomic groups also varied along the sites. The correlation between the physico- chemical parameters and Cyclops abundance at the four study sites was indicative of the effects of ecological factors on the Cyclops and the potential of cyclops to be used as bioindicators of environmental perturbation in the reservoir
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    Assessment of physico-chemical parameters and cyclopoid copepod abundance in awba Reservoir, Ibadan
    (2014) Tyokumbu,E.T
    A study was carried out on the effects of physico-chemical parameters on the microscopic cyclopoid copepod abundance in Awba reservoir, University of Ibadan between January and February 2005.McMaster Microscope was used to observe and identify the copepods while a water quality test kit was used to assess the physico- chemical parameters. The results showed a variation in the physico-chemical parameters of the sites with ranges for dissolved oxygen: 21.2mg/l ± 0.85 to 24 mg/l ± 1.71, biochemical oxygen demand (BOD): 10.3 mg/l ±0.57 to 11.2 mg/l ±1.4. Temperature 28.10C±0.23 to 300C ±2.07, pH 7.2±0.13 to 7.5±0.27 and conductivity 304 µS/cm ± 42.7 to 330.5 µS/cm ± 70.3. Diverse taxonomic groups of cyclops were encountered at the four study sites in Awba Reservoir during the sampling period. The dominant groups varied across the sites. For site 1, Tropocyclops mellonbyi was dominant with a Berger-Parker Diversity Index (BPDI) of 92%, for site 2, Tropocyclops mellonbyi, Halicyclops korodiensis; Thermocyclops iwogiensis were present with a BPDI of 72%, 16% and 12%, respectively. For site 3, Tropocyclops mellonbyi and Halicyclops korodiensis were encountered with a BPDI of 88% and 12% for site 4, Ectocyclops ilariensis had a BPDI of 100% as the only cyclop species. The number of taxonomic groups also varied along the sites. The correlation between the physico- chemical parameters and Cyclops abundance at the four study sites was indicative of the effects of ecological factors on the Cyclops and the potential of cyclops to be used as bioindicators of environmental perturbation in the reservoir
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    Bioaccumulation of arsenic and uranium in two fish species ( clarias lazera and Tilapia zilli ) from alaro stream in Ibadan, Nigeria
    (2014) Tyokumbu,E.T; Okorie,T.G; Umma,B.S
    Studies were carried out on the bioaccumulation of arsenic (As) and uranium (U) in the organs of two fish species (Clarias lazera and Tilapia zilli) from Alaro stream in Ibadan, Nigeria. Fish were collected from the entire Alaro stream downstream of the industrial effluent outfall for six months from July to December using cast and gill nets. Dissections were carried out to remove the gills, fins, gut, liver, bones and muscle for acid digestion. Samples were analyzed using the inductively coupled plasma-mass spectrometer (ICP-MS) with quality assurance of the results obtained using bovine liver standard reference material (SRM) from the National Institute of Standards and Technology (NIST).The results show that As and U levels in the fish organs exceeded the World Health Organization (WHO) guideline limit and other international standards. This indicates that fish caught in Alaro stream is unfit for human consumption since it contains the carcinogens: arsenic and uranium. It is recommended that the polluted stream should be monitored, treated and controlled for food security and other human uses of the stream