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Background&Objective: Heavy metals have a high resistance against degradation. So their amounts in human food chain, such as fish, may be increased even several times either in water or air, due to bioaccumulation. These amounts are potentially dangerous to human. This study was done to determin of heavy metals in edible tissue of Lutjans Coccineus and Tigeratooh Croaker in the Persian Gulf. Materials&Methods: 60 samples of Lutjans Coccineus and Tigeratooh Croaker were collected randomly after preparation and chemical digestion for trace elements determination. Pb, Cr, Cd and Ni were determined by flame atomic absorption in 2003. Results: Average value of Pb, Cr, Cd and Ni in the edible tissues of two fish species, Lutjans Coccineus 0.442,0.333,0.063 and 0.322 and Tigeratooh Croaker of were 0.48, 0.062, 0.064 and 0.48 ppm (dry weight basis), respectively. Conclusion: Results indicated that the mean concentrations due to heavy metals in these two species were less than acceptable limit of WHO, but related concentrations of Pb, Ni, Cd and Cr in 27%, 25%, 8% and 3% of individual studied samples respectively were more than upper acceptable limit of WHO.

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Background and Objective: Bioabsorbat is one of the most effective methods for the removal of heavy metals from industrial sewages. This study was done to assess the evaluation of Copper removal from industrial sewages by the Green microalgae Chlorella vulgaris.

Methods: This descriptive-analytic study was done on three samples from Bahonar Kerman copper industry sewage samples and 63 copper biosorption synthetic samples by Green microalgae Chlorella vulgaris at a constant temperature of 25°C, optimum pH 6 and contact time of 60 minutes and adsorbent concentration of 2 g/L. The rate of residual copper was determined using atomic absorption instrument. The adsorption isotherms and metal ions kinetic modeling on to the adsorbent were determined based on Langmuir isotherm, Freundlich and kinetics of type I and II.

Results: The removal efficiency was determined as 82.62% and 91.5 % in Copper real examples and synthetic samples, respectively. Based on the obtained results, copper absorption followed Langmuir model and second order kinetic equation (P<0.05).

Conclusion: Due to high absorption potential of Green microalgae Chlorella vulgaris, this method can be effectively used for copper removal from industrial sewages.

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Background and Objective: Fish is one of the creatures which have the bio-accumulation of heavy metals. Terapon puta belongs to the order of Perciformes, is a benthic species in the waters of the Persian Gulf. This study was performed to evaluate the bio-accumulation of iron and nickel metals in the muscle of Terapon puta.
Methods: This descriptive-analytical study was performed on 30 pieces of Terapon puta caught in the Jefreh pier area of Bushehr, north of the Persian Gulf during the summer of 2019. Length (mm) and total weight (g) of fish were measured. The concentrations of iron and nickel in fish muscle tissue for human consumption were compared with international standards and calculated according to the US Environmental Protection Agency (USEPA) method for fish consumption, estimated daily uptake (EDI), and pollutant risk index (CR). After preparation, bioassay and, digestion of fish muscle with concentrated nitric acid, the concentration of iron and nickel (mg/kg) in muscle tissue was measured with ICP-OES.
Results: The mean concentrations of iron and nickel in muscle tissue of fish samples were calculated 36.08±15.72 and 0.39±0.13 mg/kg, respectively. There was a significant difference between the concentrations of iron and nickel in the muscle tissue of the Terapon puta in the sampling area (P<0.05) and these values were lower than the standard and meaningless the muscle tissue of the Terapon puta in the sampling area compared to the FDA standard. The highest concentration of metals was observed in the length class of 20-25 cm and weight class of 230-260 g. Linear regression analysis showed that a strong increase (R²=0.9) between the concentration of iron and nickel with the length and total weight of fish. The daily uptake of both metals was obtained by consuming Terapon puta muscle tissue for consumers below the USEPA reference dose. The concentration of iron in the muscle tissue of Terapon puta was lower than the international standards. Nickel concentration was more than allowable limit according to WHO standards. The carcinogenicity risk index for nickel was acceptable.
Conclusion: Concentrations of iron and nickel in Terapon puta were considered acceptable for human consumption in terms of toxicity. The risk index for Terapon puta was less than one; therefore, the consumption of Terapon puta will not cause adverse health effects for consumers.

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Background and Objective: Population growth and pollution caused by the discharge of all kinds of urban, industrial, and agricultural sewage, leachate from landfills, and surface water runoff cause an increase in pollution of water sources. The entry of heavy metals into the environment, especially aquatic ecosystems, due to entering the food chain and jeopardizing human health is one of the concerns of society. This study was conducted to determine the level of heavy metals in muscles of Cynoglossus arel and Pomadasys kaakan fishes in Boushehr coastal waters, north of the Persian Gulf.
Methods: This descriptive study was conducted on twenty pieces of Cynoglossus arel and twenty pieces of Pomadasys kaakan fishes take place from three coastal stations of Boushehr, north of the Persian Gulf, Iran during spring of 2022. The samples were randomly selected from the fish market. After preparation, bioassay, and digestion of fish muscle by concentrated nitric acid, the concentration of heavy metals including nickel, zinc, copper, lead, and cadmium (µg/g) in the muscle tissue was measured by ICP-OES device. The concentration of heavy metals in the fish muscle tissue for human consumption was compared with international standards (FAO, WHO, FDA, NHMRC, and UKMAFF). According to the method of the US Environmental Protection Agency for fish consumption, daily absorption estimates and heavy metal risk indicators were calculated.
Results: The risk potential index for both species was less than one. The daily and weekly absorption of Cynoglossus arel (zinc > copper > nickel > lead > cadmium) and Pomadasys kaakan (copper > zinc > nickel > lead > cadmium) were determined. The mean concentration of heavy metals nickel, zinc, copper, lead, and cadmium in the muscle tissue of the studied species was determined to be 1.88±0.07, 27.16±8.11, 11.55±4.12, 1.14±0.06, and 0.19±0.03 µg/g, respectively. The highest amounts of studied metals in aquatic animals were zinc > copper > nickel > lead > cadmium. The concentration of metals in the analyzed samples was lower than the international standards.
Conclusion: Regarding toxicity, the concentration of metals in Cynoglossus arel and Pomadasys kaakan was evaluated as acceptable for human consumption. In addition, the amount of risk potential and risk index for non-cancerous diseases in adults and children in fish muscle tissue was less than 1, and the consumption of this fish does not cause any problems for human health.