Abstract: The concentration of heavy metal (Cd, Pb, Fe, Zn, Cu) in Clarias gariepinus collected from fish markets; Fanibi (Station I) and Fiwasaye (Station II) in Akure metropolis, Ondo state, Nigeria were investigated to ascertain the safety for the consumers. 60 samples were collected from the two markets in three batches (I, II, III) for a period of six months and analyzed for heavy metals in the gills and muscles of the fish. Also, the Health Risk Index (HRI) was used to determine the health risk of these metals to the consumer. The results showed that the investigated metal concentration was higher in station I than station II, except Pb having higher concentration in station II than station I. In both stations, the highest concentration of Fe was recorded in the gills (12.60 ± 1.51; 6.94 ± 1.38) and muscles (3.72 ± 0.09; 3.86 ± 0.33) of samples in batch I. Also, the HRI revealed that consumption of Clarias gariepinus from these study areas did not pose any health risk (HRI < 1). In addition, concentrations of the heavy metals were all below the permissible limits recommended by FAO/WHO.
Abstract: Investigations on the accumulation of heavy metals in
water and sediments of river Ogbese were carried out between
December 2010 and February 2011 using Atomic Absorption
Spectrophotometer. Etheria elliptica a sessile organism was also used
to determine the concentration of heavy metal in the aquatic
environmental. In water, Cu had the highest concentration (0.55 –
0.13 mg/l ±0.1) while in sediments, the highest value obtained was in
Fe (1.46-3.89mg/l±0.27). The minimum concentrations recorded
were in Pb; which was below detectable level. The result also
revealed that the shell accumulate more heavy metals than the flesh
of the mussel with Cu in the shell exhibiting a negative correlation
with all the metals in the flesh. However, the condition factor (K)
value is 6.44, an indication of good health. The length-weight
relationship is expressed as W = -0.48 x L 1.94 (r2 = 0.29) showing the
growth pattern to be negatively allometric.