Concentration of heavy and toxic metals Cu, Zn, Cd, Pb and Hg in liver and muscles of Rutilus frisii kutum during spawning season with respect to growth parameters



 Concentration of heavy and
toxic metals Cu, Zn, Cd, Pb and Hg were determined in liver and muscles of Rutilus
frisii kutum and their relationships with growth parameters (length, age,
condition factor) and hepatosomatic index were examined. Thirty-six fish
samples were collected from February through March 2009 caught by beach seine in
the southwest parts of the Caspian Sea. Atomic absorption and Hg determined
concentrations of Cd, Pb, Zn and Cu by vapor method. Cadmium was recorded only
in liver samples. Range of other metals in muscle tissue were ND -0.591, 0.001-0.013,
11- 26 and 0.729 -7.261 µg.g-1dw for Pb, Hg, Zn and Cu respectively.
Highest levels of Pb, Zn, and Cu were recorded in muscles Hg and Cd in liver
samples. Growth parameters showed a significant relationship with Zn and Cd concentrations
in liver samples and only Zn concentrations in muscle samples. There was a
positive significant correlation between concentration of Cd in liver and
physiological indices (p < 0.05). Although higher
concentration of Pb was recorded in this study in comparison to previous
studies, based on Provisional Tolerable Weekly and daily Intake of fish for
human health, kutum is considered safe for human consumption. Considering the
results of this study it seems reproductive status of the fish influences heavy
metals concentration in liver and muscles of kutum and therefore concentrations
of some metals such as Zn and Cu in liver samples may not be a reliable bioindicator
for environmental pollution.