Hassan Malvandi; Nasrin Hassanzadeh
Abstract
Background and purpose: Evaluation of concentration and degree of heavy metal contamination in rivers based on sediment contamination indices is one of the important issues in ecotoxicology research. Therefore, the purpose of this study was to measure the heavy metal concentrations in the sediments of ...
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Background and purpose: Evaluation of concentration and degree of heavy metal contamination in rivers based on sediment contamination indices is one of the important issues in ecotoxicology research. Therefore, the purpose of this study was to measure the heavy metal concentrations in the sediments of the Siahrood River and to assess the health risk of these pollutants. Another purpose was to determine the status of the river in terms of contamination and non-contamination for ecotoxicology studies. Materials and Methods: Acid digestion method was used to prepare the samples. Then the concentrations of Cr, Fe, Zn, As, Se, Ni, Co, Al and Mn were measured using ICP-OES. Pollution and ecological risk indices were also calculated. Results: The mean concentrations of chromium, iron, zinc, arsenic, selenium, nickel, cobalt, aluminum and manganese were 33.02, 7309.82, 42.61, 13.15, 13.36, 12.88, 6.58, 159.28 and 384.51 µg/g dw, respectively. Most of the studied elements were in the first category of pollution assessment indices. Conclusion: The results based on contamination indices and comparison with sediment quality guidelines showed that concentrations of Cr, Se and As are of concern and could potentially be a threat to the health of organisms. For ecotoxicology studies, this river is considered to be relatively contaminated in terms of Cr, Se and As and non-contaminated for other studied elements. However, further studies and monitoring of pollutants in this ecosystem are essential for making proper and effective management decisions.
Sepideh Yeganeh Shali; Ghasem Rahimi; Leila Jahanban; Salahedin Moradi; Eisa Ebrahimi
Abstract
Background and Aim: In recent decades, industrial, agricultural and urban activities have led to pollution and accumulation of heavy metals in soils and plants which directly or indirectly affects humans and animals lives. Nowadays, pollutant accumulation in most agricultural products is much higher ...
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Background and Aim: In recent decades, industrial, agricultural and urban activities have led to pollution and accumulation of heavy metals in soils and plants which directly or indirectly affects humans and animals lives. Nowadays, pollutant accumulation in most agricultural products is much higher than the permissible limit due to the excessive use of fertilizers. The main objective of the present study was to investigate the accumulated proportions of heavy metals such as copper, lead and cadmium in different tissues of laboratory rat.
Materials and Methods: In this study, the accumulation and distribution of heavy metals were investigated in different organs of rats under various nutritional conditions. The experiment was conducted in a completely randomized design with greenhouse strawberry treatments in three groups.Different groups of rats (27 rats) were fed strawberries infected with heavy metals by oral gavage within a three-month period.
Regarding the average weight of rats, 0.5 gram of fresh strawberry was considered for each rat. In addition, heavy metals solution including cadmium (15.773 mg / l), lead (41.560 mg / l) and copper (9.445 mg / l) were exerted to the plant. In the next stage of procedure, heavy metals (cadmium, copper and lead) accumulated in different organs of the rats (kidney, liver, pancreas, Testicle, spleen, and brain) were measured.
Results: Results showed that the concentrations of studied heavy metals in the strawberries were 7.7, 26 and 3.2 mg/kg for cadmium, lead and copper respectively, which were higher than Iranian standard level. The statistical results showed that there was a significant difference between the different organs in the intake of the heavy metals, so that in the infected treatment, the most and lowest amounts of cadmium were in the kidney (0.41 g / day) and the brain (0.24 g / day), respectively. Heavy metals caused reduction in the rate of weight gain of rats. The accumulation of these elements was higher in the kidney, liver and pancreas than other organs. The least accumulation of heavy metals was related to the rat’s brain, while highest proportion of the heavy metals accumulation was in the kidney.
Conclusion: The results demonstrated that if strawberry quality is not evaluated properly and distributed throughout community in the contaminated form, it can pose many harmful effects on the community’s health. Therefore, the quality control should be carried out with high precision.
Pegah Nakhjirgan; Mohammad Hadi Dehghani
Abstract
Background and objective: Increased use of nanoparticles in industries leads to entering hazardous substances to environment. Nanoparticle toxicity due to release of toxic substances into the environment is a concern for communities. One of the common nanoparticles ingredients are zinc oxide. In this ...
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Background and objective: Increased use of nanoparticles in industries leads to entering hazardous substances to environment. Nanoparticle toxicity due to release of toxic substances into the environment is a concern for communities. One of the common nanoparticles ingredients are zinc oxide. In this study toxicity of the solution containing the Reactive Red 120 dye after Nano-catalytic process UV/ ZnO using biological test Daphnia magna was studied. Methods: this is a fundamental – practical study, which done on laboratory scale. Toxicity assay tests were carried out using Daphnia magna a bio-indicator. Then results of toxicity tests using SPSS software were analyzed and Lc50were determined. Results: Results showed that the Lc50 value at 24,48,72,96 hr is 73.16, 55.93, 41.32, 30.45 mg/l and the toxicity unit values are 1.36, 1.78, 2.42, and 3.28, respectively. Conclusion: the results generally indicated that toxicity increased in process and over time and showed that Reactive Red 120 after UV/ ZnO process was toxic to Daphnia magna. Paper Type: Research Article