ISSN 2375-0715
African Journal of Fisheries Science ISSN 2375-0715 Vol. 5 (1), pp. 210-214, January, 2017. © International Scholars Journals
Full Length Research Paper
A study of the levels and seasonal variation of heavy metal contamination of E. radiata from creeks in Burutu area of Delta state, Nigeria
James Azuka, Adaku Ijeoma and Ijeagha Ifeatu
Department of Fishery and Aquaculture, Faculty of Agriculture & Natural Resource Management, Ebonyi State University, Abakaliki, Ebonyi State, Nigeria.
*Corresponding Email: [email protected]
Accepted 12 November, 2016
Abstract
Levels of heavy metal concentrations in tissues of Egeria radiata from Obotebe and Gbekobor Creeks in Burutu Local Government Area were investigated. E. radiata samples were collected fortnightly for 12 months in 2008. The soft tissues of E. radiata were extracted, weighed and dried in oven for three days at 600C. Ten grams of the dried samples were homogenized and digested before analysis using the atomic absorption spectrophotometer (AAS) to determine levels of heavy metals such as (copper, lead, manganese, cadmium, mercury, chromium and nickel). The results obtained showed that tissues of E. radiata from the creeks were contaminated with heavy metals. The mean concentrations of heavy metals in tissues of E. radiata followed an increasing sequence of Hg < Cd < Cr < Mn < Pb < Cu < Ni. Heavy metal concentrations in tissues of E. radiata were higher but were not significant in the dry season than in the rainy season. Levels of heavy metals in tissues of E. radiata were found to be below the FAO/WHO acceptable limits of heavy metal pollution in fishes and shell fish. Mean levels of lead (Pb), manganese (Mn) and Cadmium (Cd) were found to be higher than world standard but not significant. Nickel were significantly lower than world standard. There is a need for constant monitoring of levels of heavy metals in the area of study in order to forestall any significant rise in their levels.
Key words: Heavy metals, E. radiata, creeks, Burutu, Nigeria.