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 dw 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

Bioaccumulation of heavy metals Cu, Zn, and Hg in muscles and liver of the stellate sturgeon (Acipenser stellatus) in the Caspian Sea and their correlation with growth parameters

Bioaccumulation of Cu, Zn, Hg in muscles and liver tissues of stellate sturgeon (Acipenser stellatus) from the southern Caspian Sea was measured. Effects of condition factor (CF), age and hepatosomatic index (HSI) on metal accumulation were also determined. Some 40 stellate sturgeons were collected using gill nets in winter and spring 2007-2008 from the southern shores of the Caspian Sea. Total (TL) and fork (FL) length and weight of all specimens were measured. Cross sections of first ray of pectoral fins were used for age determination. Muscle and liver samples were taken and transported to the laboratory in ice packs and kept in -20 °C prior to analyses. In the laboratory samples were oven dried, digested with HClO3 and HNO3 and diluted with dionized water to 50cc to measure Cu, Zn, and Hg concentration with a flame spectrophotometer. Sequence of metals in Acipenser stellatus was Zn>Hg> Cu in muscle tissues and Zn>Cu>Hg in liver samples. Concentration of Zn was slightly in correlation with age (R= 0.3). A negative correlation was observed between Zn concentrations with condition factor (R = -0.3). Zn concentrations were negatively correlated in muscle tissues (R = -0.3). The results were compared to international standards proposed by MAAF, EEC and NHMRC. Our study showed that accumulation of heavy metals in sturgeon tissues was influenced by concentration of metals in sediment and the physiological state of fish