Abstract:
Samples of the muscle of two species of tilapia (Oreochromis mossambicus
and O. niloticus; 17?20 cm length) were obtained from at least one reservoir
in each of the six river basins (Aruvi Aru, Kala Oya, Kirindi Oya, Ma Oya,
Mahaweli, and Walawe Ganga catchments) in Sri Lanka. The metals Ca,
Cu, Fe, K, Mg, Mn, Na, and Zn were consistently detected in the muscle
tissue. Overall, there were few differences in the concentration of metals
between the two species of fish, although there were also some statistically
significant differences (p50.05) in the concentrations of some metals in fish
obtained from some of the reservoirs. Aruvi Aru stands out as a river basin
in which the two fish species have significantly lower concentration of
metals when compared to other river basins. The concentration of the
metals studied were below WHO and FSANZ guideline values for fish,
suggesting that the consumption of the metals found in tilapia from these
reservoirs poses little risk to human health.