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The use of heavy metals
load as an indicator of the suitability of the water and fish
of Ibiekuma Stream for domestic and consumption purposes
Obasohan, E. E.
Department
of Animal Science, Faculty of Agriculture, Ambrose Ali
University, Ekpoma, Edo State, Nigeria. E-mail:
ewaensohan@yahoo.com.
Accepted
15 August, 2008 |
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The levels of Cd, Cr, Cu, Pb and Zn in the water and fish
from Ibiekuma Stream, Ekpoma, Nigeria were determined at two
locations (Upstream and Downstream) in order to ascertain
their suitability for consumption and other domestic uses.
Atomic Absorption Spectrophotometry was used to measure the
metal levels. Seasonal (dry and wet seasons) levels were
also determined. The results showed Zn mean levels were
highest with 1.12 ± 0.51 mg/l in water and 45.5 ± 7.46 mg/kg
in fish. Minimum levels were 0.005 ± 0.002 mg/l (Cd and Pb)
in water and 0.70 ± 0.22 mg/kg (Cd) in fish. Pb was not
detected in fish. Spatially, upstream location levels were
generally higher than downstream levels for all the metals
in both water and fish. Dry season levels were also
generally higher for all samples and at both locations. The
consumption of the fishes of the stream requires stringent
precautionary measures because of the high levels of Cr and
Cu which exceeded limits in food fish and could therefore
pose some health risks. It was also observed that all metal
levels in water were within drinking water limits and global
background levels for surface fresh water. The implication
of these findings is that the water of the stream could be
used for drinking and other domestic purposes.
Key
words:
Atomic Absorption Spectrophotometry, heavy metals, water,
fish, Ibiekuma Stream. |
