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.

Background and Objectives: Pentachlorophenol (PCP) is an organic compound and phenolic derivatives categorized as priority pollutants that have harmful effects on humans, animals, and plants in low concentrations. Therefore, PCP removal from water and wastewater is very important. The aim of this study was to assess the efficiency of A. niger fungus biomass in PCP absorption. Materials and Methods: This was an experimental study in which different steps of the experiments were performed. A. niger strain was prepared from Persian Type Culture Collection of Iranian Research Organization for Science and Technology (IROST). After activation in potato dextrose agar (PDA) culture plates, fungi were incubated for 7 to 10 days at 25 °C. The prepared A. niger biomass was modified by NaOH and then it was used for PCP absorption assay. The concentration of PCP was measured using high-performance liquid chromatography. Results: The findings of present study showed that contact time is an important and effective factor in the PCP absorption rate. Two hours was selected as the optimum retention time in this experiment and after that the removal percentage did not raise significantly. The results of PCP absorption in different pH demonstrated that the adsorption efficiency decreases by rising pH and initial PCP concentration. The effects of contact time, pH and initial PCP concentration on the absorption process was significant (P-value <0.001). Conclusion: The results show that absorption efficiency increases by rising retention time under constant conditions. In addition, at low pH the modified A. niger biomass could be a good absorber for PCP.