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P. Nourozifard , S. Mortazavi , S. Asad, N. Hassanzadeh ,
Volume 8, Issue 1 (3-2019)
Abstract

toxicology. Considering the specific conditions of the Persian Gulf and the impact of pollutants, the aim of the present study was to evaluation of toxic elements bioavailability from the total amount of surface sediments in the Persian Gulf.
Materials & Methods: In the present study, the total concentration and bioavailability fraction of copper, lead, zinc, cadmium, nickel, and chromium were measured at 14 coastal stations of Hormozgan province and Qeshm island. Nitric acid and perchloric acid were used to measuring the total concentration and K protease enzyme solution was used to measuring the bioavailable fraction. 
Findings: Zinc and chromium have the highest mean of total concentration, respectively. Qeshm island has more pollution than Hormozgan. The higher bioavailability and higher percentage of components were observed in lead and chromium than the other elements. With increasing concentrations of lead, chromium, and copper, the bioavailability of these elements also increased. As well as, zinc and nickel showed the lowest bioavailability. The concentration of copper, lead, and nickel was also higher than the sediments world average and the WHO / US EPA maximum, and the nickel concentration was above the ERM, PEL, and SEL.
Conclusion: Due to the low accuracy of determining the total concentration of metals in sediment toxicity for aquatics and the need to pay attention to bioavailability fraction, the probability of ecological risk of lead and chromium elements is higher than the other elements for aquatics of Persian Gulf. Zinc and nickel, have the lowest risk to the environment despite the high total concentration.
 

Negin Bayat , ,
Volume 9, Issue 3 (8-2020)
Abstract

The aim of this study was to measure the level of Arsenic, Cadmium, Nickel and Mercury in gill, muscle and hepatopancrease tissue of Aras dam Astacus leptoductylus and compare of them concentration in different body tissues. For this purpose, 271 samples of Astacus leptoductylus were randomly collected in Aras dam from December 1 to December 31, 2017 and transferred to the laboratory. After that tissue samples processed for injection in atomic absorption for apparatus for measuring the level of Arsenic, Cadmium, Nickel and Mercury. For measuring the protein, ash and moisture content of the samples AOAC method was conducted. The results showed that Arsenic, Cadmium, Nickel and Mercury were present in the Astacus leptoductylus samples and the highest level of these metals was in the muscle and the lowest in the gills. The highest level of metals existing in Astacus leptoductylus muscle was related to Cadmium (0.338± 79 0.79 ppb), and also Nickel (0.285±0.066 ppb) was in the second rank. The level of Arsenic and Mercury in muscle were ranked third and fourth. However, it was found that the total moisture content of the gills was higher than muscle and hepatopancrease tissue. On the other hand, the results of correlation between metals of different tissues of Astacus leptoductylus showed that the correlation between Cadmium and Nickel was higher than Arsenic and Nickel. The level of total protein and ash in Astacus leptoductylus muscles was higher than other tissues. The present study showed that analyzed Arsenic, Cadmium, Nickel and Mercury level were in the muscle, gill, and hepatopancrease tissue samples of the Aras dam A. leptoductylus in detectable concentrations, and Nickel and Mercury in the samples were lower than the WHO standard. As a result, the levels of metals in the Astacus leptoductylus samples collected from Aras dam were safe and reliable and therefore there is no problem.
Mohammad Gholizadeh, Behroz Mohammadzadeh, Ali Kazemi,
Volume 10, Issue 2 (4-2021)
Abstract

Fish are among the organisms that have the ability to bioaccumulate these metals. The aim of this study was to investigate the concentrations of aluminum, vanadium, tin and chromium in the muscle tissue of tapeworm and assess its potential risk. For this purpose, 30 pieces of fish were caught in July 2017 from Bushehr port, Persian Gulf. Samples were prepared according to standard laboratory methods and the concentration of heavy metals was measured using ICP-OES. The concentration of elements in the muscle tissue of fish for human consumption was compared with international standards, as well as the estimated daily, weekly absorption in children and adults, their permissible consumption and risk indicators of consumption of this fish against carcinogenic diseases. The results showed that the mean concentrations of aluminum (23.9 ±10.3), vanadium (0.15 ±0.07), tin (5.41 ±2.2) and chromium (0.34 ±0.12), based on micrograms per gram, fresh weight was observed in muscle tissue.  The absorption of the studied metals in the muscle tissue of fish was Al> Sn> Cr> V. The results showed that the permissible consumption of heavy metals with the exception of aluminum was lower than the standard of the World Health Organization. The calculation of the risk index showed that aluminum in both groups of adults and children and chromium in children have values ​​of more than one, in this regard, with continuous monitoring of heavy metal surfaces in fish offered in the market
Naser Koosej, Hojatollah Jafariyan, Abdolvahed Rahmani, Abdolrahman Patimar, Hosna Gholipoor,
Volume 10, Issue 2 (4-2021)
Abstract

In this study, coastal sediments of Qeshm, Bandar Khamir and Bandar Laft regions in Hormozgan province were studied to determine the level of contamination of heavy metals lead, nickel, zinc, iron and copper by natural processes or human activities. In order to identify environmental pollutants caused by heavy metals, shovel sampling was performed from the sediments of these areas to measure the concentration of heavy metals and determine the enrichment index. The location of the samples was determined using a GPS device and sampling of surface sediments (tidal zone) was performed at 30 stations in the study areas. Atomic absorption of flame spectrometry was used to determine the concentration of heavy metals. The results showed that the mean concentrations of heavy elements lead, nickel, zinc, iron and copper in all sampling stations showed a significant difference (p<0.05). In terms of concentration of studied elements in Qeshm region (copper: 33.76 ± 1.88, zinc: 85.44 ± 2.75, lead: 31.79±  1.23, nickel: 34.17 ± 2.29 and Iron: 38000±691.21 μg/g) compared to Bandar Khamir (copper: 26.84 ± 2.30, zinc: 77.54 ± 2.12, lead: 24.71±  1.37, nickel:25.82± 1.30 and iron: 36810± 482.882 μg/g) and Bandar Laft (copper: 22.74± 2.42, zinc: 65.22±2.61, lead: 19.93± 1.32, nickel: 21.70±2.06 and iron: 35560±1014.56 μg/g) had higher contamination. The results also showed that the metal enrichment factor is low in all sediment samples and in terms of Müller geochemical index, the degree of soil contamination is in the category of non-contaminated soils.
Habib Sarsangi Aliabad, Abolfazl Naji, Seyed Reza Seyed Mortezaei, Iman Sourinejad, Arash Akbarzadeh,
Volume 10, Issue 3 (9-2021)
Abstract

Biofloc technology has mentioned as a new tool for sustainable aquaculture development and has overcome the problems of water scarcity and discharge of aquaculture effluents to the environment. In this system, nitrogenous wastes (Ammonia and Ammonium) are simultaneously recovered by bacteria and converted into microbial proteins that can be consumed by aquatic animals. The purpose of this study was to investigate the factors affecting the production of biofloc and evaluate it for use in aquaculture. The effect of different temperature levels (24, 28, 32 °C), salinity (0, 4, 8 g/l)  ,and C/N ratio (10:1, 15:1, 20:1) which are the main key factors to the formation and function of biofloc system was evaluated by using a response surface method designing. Moreover, the influence of those factors on total ammonia nitrogen, nitrite, nitrate, floc volume, protein, and lipid content of biofloc was investigated. The results showed that the temperature had a significant effect on floc volume and protein content of biofloc (P < 0.05), but it had no significant effect on other nitrogenous compounds and lipid content (p > 0.05). The protein, lipid and moisture of biofloc particles were decreased by increasing salinity significantly (P < 0.05). Also, TAN and nitrite concentration influenced by C/N ratio inversely. According to the factors Optimization, providing 27 °C and C/N ratio of 18:1 in brackish water and 29 °C and C/N ratio of 14:1 in fresh water resulted in high quality biofloc production and control of nitrogenous wastes in water.
Mohammad Seddiq Mortazavi, Seyedeh Laili Mohebbi Nozar, Sana Sharifian, Khosrow Aeinjamshid, Hadi Koohkan, Mohsen Mazravi,
Volume 13, Issue 1 (1-2024)
Abstract


In this study, a comprehensive assessment of the occurrence and spatial distribution of heavy metals including Nickel, Lead, Zinc, Copper, Cadmium and Chromium, as well as, TPHs in the surface sediments of the coastal areas and far from the coast of the Persian Gulf in Bushehr and Khuzestan provinces were performed to identify the possible sources of sediment contamination and determining the degree of pollution. Eight pollution indices were used to evaluate the quality of sediments in terms of heavy metal and TPH pollution. The investigated areas could be distinguished by a significant degree of heavy metal pollution of Nickel, Cadmium and Zinc. High concentrations of Nickel and Zinc were observed in stations around Nakhiloo, Bushehr. The comparison of average pollution indices between regions showed that both Bushehr and Khuzestan provinces, respectively, with the average of contamination degree (CD) (20.25 and 22.11), modified contamination degree (MCD) (3.38 and 3.69), pollution load index (PLI) (31.17 and 57.57), potential ecological risk index (PERI) (353.54 and 349.39) have a significant degree and risk of Nickel and Cadmium pollution, especially in Nakhiloo area, Bushehr. Investigating the spatial fluctuations of the concentration of TPHs in two provinces showed an increasing trend from Bushehr to Khuzestan. However, areas were located in no pollution or low pollution zonation and were safe from the adverse biological effects of TPHs. Comprehensive and impressive strategies to control and reduce these pollutions, especially in polluted areas, should be considered, so that the sources of these pollutions be managed.
 
Mohammad Seddiq Mortazavi, Leili Mohebbi-Nozar, Sana Sharifian, Sharareh Khodami, Ali Salarpoori, Hadi Koohkan, Gholamali Akbarzadeh,
Volume 13, Issue 4 (11-2024)
Abstract

The dramatic increase in heavy metals, their stable nature, and high toxicity, is gradually becoming a global crisis. In a recent study, a comprehensive assessment of the spatial distribution of heavy metals including Cd, Pb, Ni, Cu, Zn, and Cr was performed in industrial and commercial areas, including the sediments of 32 stations located in the area of Jask, Bandar Abbas, Qeshm, and Bandar Lange during the 2021to 2022. In this area, the concentration of heavy metals showed significant spatial variations between the areas. The maximum concentration of Cd was 0.55 μg/g in the first station of Gasheh. The second station of Khor Langeh had the highest Pb concentration with an average of 10.25 μg/g. The maximum concentration of Cr was 2420.33 μg/g in the second Shahid Bahonar station. The highest Zn concentration of 268.56 μg/g was observed in the first station of Suru beach. In the first station of Shahid Rajaei port, the highest concentration of Cu was observed at 18.36 μg/g. The maximum concentration of Ni was 519.02 μg/g in the second station of Shahid Bahonar.The stations located in Shahid Bahonar port, Suru beach, and Khor Gorsouzuan had a higher pollution intensity than other places and significant pollution risks, especially in terms of Cr, Ni, and Zn. In these areas, Cr was identified as the most dangerous metal. It is necessary to consider comprehensive strategies to control and reduce these heavy metal pollutions, to identify and manage the sources of these pollutions.
 


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