Iranian Journal of

Backgrounds and Objectives:There have been always concerns regarding to consumption of aquatic products, particularly fish, due to the possibility of heavy metals bioaccumulation in aquatic creatures organs, throughout the world.Aresearch project was carried out to assess the level of concentrated total mercury in different tissues of Silver carp as the most consumed fish from Sanandaj Ghesglagh reservoir in the region.
Materials andMethods:Twenty four silver carp were captured randomly during July to December 2009. Prior measuring mercury concentrations in white muscle, red muscle and liver tissues by AdvancedMercuryAnalyzer (Model Leco, 254AMA) on the dry weight basis, biometry procedure was done.
Results: Mean accumulated mercury in white muscle, red muscle and liver tissues were 367 (S.E.± 26.43), 311 (S.E.± 32.22) and 251 (S.E.± 28.70) ng gr -1 on the dry weight basis, respectively. Pair comparisons between the level of concentrated mercury in all tissues, except white muscle tissues (F5, 18 = 1.52, P = 0.2332) showed a significant difference (P < 0.05).
Conclusion: The level of accumulated mercury in muscle and liver tissues of all samples weighted above 850 grams were higher than the established limits by WHO, FAO and EPA. Our results emphasis that the consumption of silver carp from Sanandaj Gheshlagh Reservoir might place the health of all those peoples who live in the region at risk.

Background and Objectives: In the recent years, we confront to harmful effects of toxins such as herbicides on aquatic species due to irregular consumption of these compounds in agricultural operations and drainage of them to water ecosystems. In the present study, the effect of 2,4-D + MCPA “the frequently used herbicide in Kurdistan province” was assessed on the hematological parameters and liver enzymes in rainbow trout as the main aquatic species farmed in this area. Materials and Methods: After determination of LC50 using Probit model, 60 healthy trout fish with an average weight of 97 g were divided into two groups. The first group was considered as control and in the second treatment group, 1 cc/L herbicide (equivalent to 360 mg/L 2,4-D + 315 mg/L MCPA) was used. After 72 hours, hematology parameters including total number of red and white blood cells, differential count of white blood cells, hematocrit, and serum levels of ALT and AST enzymes were measured. Results: The values of blood tests including leukocytes, monocytes, and eosinophils in the toxin group was significantly increased in comparison with control group, whereas, the values of lymphocytes, erythrocytes and hematocrit were significantly decreased in toxin group compared with the control (p<0.05). There was no difference between the level of neutrophils in the treatment and control groups. The levels of liver enzymes, ALT and AST, in the treatment group increased significantly compared with the control group (P<0.05). The mortality rate after of 72 hours was 25% in the group treated with the toxin. Conclusions: Erythrocytes and hematocrit amounts of blood in rainbow trout were decreased due to exposure to 2,4-D + MCPA herbicide that eventually leads to oxygen deficiency and inefficient blood supply. The contact of red blood cells and hematopoietic tissues to toxin and destruction of them are led to loss of the cells in the blood. On the other hand, liver, kidney and gills autopsy of the wasted fish and the increasing of liver enzymes in the blood and tissues showed that exposure to the toxin lead to damages in fish blood cells and tissues.