Distribution and pollution level of nickel and vanadium in sediments from south part of the Caspian Sea, Iran

765-771Distribution and pollution level of nickel and vanadium in sediment from south part of the Caspian Sea, north of Iran, were studied. Sediment samples obtained by Van Veen Grab from four stations, including, Turkaman, Amirabad, Fereydunkenar and Noushahr along the south part of the Caspian Sea, during fall of 2015 and april, summer and winter of 2016. The concentrations of metal were ranged from 21.63 µg/g to 55.45 µg/g for nickel and from 58.23 µg/g to 146.27 µg/g for vanadium in sediments samples collected from all stations. There was significant difference in metals concentration between different stations along the Caspian Sea (P < 0.05), and the highest mean concentration of metals was absorbed in Fereydunkenar estuary, followed by Amirabad, Turkaman and Noushahr, respectively. The results showed that there were significant differences between metals pollution during four seasons (P < 0.05), and the highest concentration of metals were absorbed in dry season (summer) and the lowest concentration in wet season (winter). There was a positive correlation between nickel and vanadium concentration in sediment samples, and the Pearson correlation was (r = 0.67) between nickel and vanadium in sediment samples. The positive correlation between heavy metals can be related to same source of both metals in the environment. Based on our results, anthropogenic activities such as oil industry and agriculture activities are the main sources of pollution in the coasts along south part of Caspian Sea

Mercury levels in selected tissues of shrimp penaeus merguiensis from persian gulf

1025-1034Levels of mercury in tissues of Penaeus merguiensis from the Persian Gulf, was investigated. This study assessed the relationship between mercury levels in hepatopancreasn tissue, muscle and gonads with sex and season. Mercury content varied with type of size and sex. Results showed that hepatopancreas accumulate higher levels of the mercury in comparison to muscle and gonads. There was significant difference (p<0.05) in mercury levels between P. merguiensis sexes, higher mercury levels found in female than in males. There was significant difference (p<0.05) in mercury levels between different seasons, higher mercury levels found in July (summer season). The variation in mercury levels among the tissues is likely to have resulted from metal bioavailability, changes in tissue composition, organism size, sex and season

Distribution of heavy metals in (Fe, Hg, Ni and Pb) sediment and blue crab, Portunus pelagicus from four estuaries, Persian Gulf

1035-1042Present study consist levels of heavy metals (Fe, Hg, Ni and Pb) in sediments and tissues of blue swimming crab, Portunus pelagicus from the Persian Gulf coasts, south Iran. The concentration of heavy metals in sediments at all sampling stations occurs in descending order of Fe > Ni > Hg > Pb. This study assessed the relationship between metals trace in hepatopancreasn tissue, muscle and exoskeleton with carapace width and weight. Significant increase in the metals levels in hepatopancreasn tissue (p<0.05) with an increase in carapace width and weight for this species. Hepatopancreasn accumulate higher levels of the metals in comparison to muscle and exoskeleton. Variation in heavy metals levels among the species is likely to have resulted from metal bioavailability, changes in tissue composition, organism size, age and locations