<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Heavy metals are present in low concentrations in reservoirs, but seasonal anthropogenic activities usually elevate the concentrations to a level that could become a health hazard. The dry season concentrations of cadmium, copper, iron, lead, mercury, nickel and zinc were assessed from three sites for 12 weeks in Oyun reservoir, Offa, Nigeria. Triplicate surface water samples were collected and analysed using atomic absorption spectrophotometry. The trend in the level of concentrations in the three sites is site C > B > A, while the trend in the levels of the concentrations in the reservoir is Ni > Fe > Zn > Pb > Cd > Cu > Hg. Ni, Cd, Pb and Hg were found to be higher than the WHO guidelines for the metals in drinking water. The high concentration of these metals was from anthropogenic watershed run-off of industrial effluents, domestic sewages and agricultural materials into the reservoir coming from several human activities such as washing, bathing, fish smoking, especially in site C. The health effects of high concentration of these metals in the reservoir were highlighted. Methods for the treatment and removal of the heavy metals from the reservoir during water purification such as active carbon adsorption, coagulation-flocculation, oxidation-filtration, softening treatment and reverse osmosis process were highlighted. Other methods that could be used include phytoremediation, rhizofiltration, bisorption and bioremediation. Watershed best management practices (BMP) remains the best solution to reduce the intrusion of the heavy metals from the watershed into the reservoir.</p></abstract>

Heavy metals are present in low concentrations in reservoirs, but seasonal anthropogenic activities usually elevate the concentrations to a level that could become a health hazard. The dry season concentrations of cadmium, copper, iron, lead, mercury, nickel and zinc were assessed from three sites for 12 weeks in Oyun reservoir, Offa, Nigeria. Triplicate surface water samples were collected and analysed using atomic absorption spectrophotometry. The trend in the level of concentrations in the three sites is site C > B > A, while the trend in the levels of the concentrations in the reservoir is Ni > Fe > Zn > Pb > Cd > Cu > Hg. Ni, Cd, Pb and Hg were found to be higher than the WHO guidelines for the metals in drinking water. The high concentration of these metals was from anthropogenic watershed run-off of industrial effluents, domestic sewages and agricultural materials into the reservoir coming from several human activities such as washing, bathing, fish smoking, especially in site C. The health effects of high concentration of these metals in the reservoir were highlighted. Methods for the treatment and removal of the heavy metals from the reservoir during water purification such as active carbon adsorption, coagulation-flocculation, oxidation-filtration, softening treatment and reverse osmosis process were highlighted. Other methods that could be used include phytoremediation, rhizofiltration, bisorption and bioremediation. Watershed best management practices (BMP) remains the best solution to reduce the intrusion of the heavy metals from the watershed into the reservoir.

Seasonal assessment, treatment and removal of heavy metal concentrations in a tropical drinking water reservoir

Department of Zoology, University of Ilorin, PMB 1515, Ilorin, 240003, Nigeria

Ekológia (Bratislava)

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Heavy metals are present in low concentrations in reservoirs, but seasonal anthropogenic activities usually elevate the concentrations to a level that could...

Seasonal assessment, treatment and removal of heavy metal concentrations in a tropical drinking water reservoir

Published Online: May 28, 2016

Page range: 103 - 113

DOI: https://doi.org/10.1515/eko-2016-0008

Keywords
heavy metals, anthropogenic, health hazard, treatment, watershed

© 2016 Moshood Keke Mustapha et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Seasonal assessment, treatment and removal of heavy metal concentrations in a tropical drinking water reservoir

Published Online: May 28, 2016

Page range: 103 - 113

DOI: https://doi.org/10.1515/eko-2016-0008

Keywordsheavy metals, anthropogenic, health hazard, treatment, watershed

© 2016 Moshood Keke Mustapha et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
heavy metals, anthropogenic, health hazard, treatment, watershed