Assessing heavy metal content of muscle tissue and caviar of Acipenser persicus and Acipenser stellatus in southern Caspian Sea

We sampled 139 specimen of Acipenser persicus and 103 Acipenser stellatus over the years 1998-1999 in five fishing zones of the southern Caspian Sea for heavy metal contamination assessment. Flame Atomic Absorption Spectrophotometry was used to determine contamination of the specimens with Zn, Cu, Cd, and Pb and cold vapor method for Hg.
The mean age for A. persicus and A. stellatus was 17.6±2.6 years and 11.9±1.8 years, respectively. The mean concentrations of heavy metals assessed for dry weight of the muscle tissues and caviar in A. persicus were 26.9 and 65.9 µg/g for Zn, 1.8 and 4.2 µg/g for Cu, 0.61 and 0.111 µg/g for Pb and 0.61 and 0.005 µg/g for Cd. The wet weight concentration of Hg in the muscle tissue and caviar of the fish were 0.06 and 0.007 µg/g respectively. For A. stellatus we determined the mean concentration of heavy metals in dry weight of the muscle tissue and caviar to be 27.4 and 57.8 µg/g for Zn, 1.64 and 4.85 µg/g for Cu, 0.481 and 0.112 µg/g for Pb and 0.59 and 0.005 µg/g for Cd while the wet weight concentration of Hg were 0.05 and 0.008 µg/g. By international standards, the contamination of the muscle tissue and caviar samples with the heavy metals in the two sturgeon species are well below maximum allowable for human consumption.