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Showing 68 results for Metals
Efficiency of the electrokinetic process in copper recovery from the waste of the mine
Mohammad Javad Zoqi, Mohammad Amin Rasooli, Behnoosh Khataei, Mohammad Reza Doosti,
Volume 16, Issue 2 (9-2023)
Abstract
Background and Objective: Mining is one of the important economic activities all over the world. It causes the release of various emissions, especially heavy metals in the soil, due to the weak exploitation and improper disposal of mineral wastes. Different techniques are used for soil remediation and heavy metal extraction; including the electrokinetic method (so effective in fine-grained soils). In this research, the electrokinetic process was used to extract copper from the waste of the mine in Birjand.
Materials and Methods: In this research, a 24 cm long PVC reactor was used. The retention time was 2, 4, and 6 days and the voltage gradient was 1 V/cm. Graphite electrodes and electrolyte solutions of nitric acid and citric acid were investigated for copper extraction. The electrode polarity was alternately changed in order to pH control and improve the extraction process.
Results: According to the results, the highest removal efficiency (54%) was obtained after 6 days using 0.1 M citric acid and distilled water in the anode and cathode reservoir, respectively. Further, by 24-hour polarity reversing, the copper removal efficiency increased to about 60%.
Conclusion: The use of citric acid in anode was more effective than nitric acid, leading to more copper removal. In addition, by periodically polarity change and keeping the soil pH in the neutral range, further dissolution of the metal and reducing its sedimentation in the soil occurred. As a result, the rate of its transfer outside the treatment area and removal efficiency increased.
 

Investigating the factors of pollution and the health risk caused by heavy metals in the dust inside the cabin and air filter of different cars in Ahvaz city
Alireza Zarasvandi, Maryam Delphi, Nadia Azizi, Fatima Rastmanesh, Gazelle Zarasvandi,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: During the last few decades, heavy metal pollution in indoor dust has been widely studied; While, the quality of the environment inside the cars has not been considered enough. Therefore, the specific objectives of this study generally include investigating the levels of selected heavy metals in the dust of private cars collected from Ahvaz city, as well as evaluating the health risk of carcinogenesis and exposure to the dust inside these cars through ingestion, inhalation, and skin absorption.
Materials and Methods: 10 cars were selected for this study. The condition of choosing the cars was not to wash the car for a week. Then, samples were collected and coded from the dust of the air conditioner filter and the cabin of each car. To determine the composition of heavy metals, spectroscopic analysis (ICP) was performed on the samples.
Results: The study of non-carcinogenic risk index (HI) in the present study indicates that the values of more than 1 and the health risk is high. The sequence of HI index values for heavy metals was obtained as  Pb>Cu>Cr> Fe> Zn> Cd> Ni. Evaluated risks from different pathways in children was HQing < HQinhder while in adults follows HQingder< HQinh process. Additionally, the values of enrichment factor of the studied samples showed the maximum and minimum values for Cu (4.3) and Ni (8.3), the maximum and minimum geoaccumulation index for Fe (12.75) and Ni (1.9) and the amount of integrated pollution and pollution index were estimated to be 1.34+E27 and 2.07+E9, respectively, indicating the average range for the studied heavy metals.
Conclusion: According to this study, the risk of non-carcinogenic risk of heavy metals (except Fe and Cu) for children is estimated to be higher than that of adults. Furthermore, the investigation of the CR index for the three carcinogenic heavy metals (cadmium, chromium, and arsenic) has exceeded the safe level, which indicates ingestion and inhale as the target pathways for the worst adverse effects of heavy metals in children andadults, respectively. In the present study, the amount of heavy metals studied is more than the set standards. The results of the current study showedthe more enrichment of heavy metals in the car filter as compared with  the cabin.
 

Toxic elements (Fe, Pb, and Cu) contents in surface sediments and native aquatic plants (Typha Latifolia and Nasturtium microphyllum) tissues of Lar river: evaluation of biomonitoring and bioremediation capability
Fatemeh Kakouei Dinaki, Mehrdad Cheraghi, Bahareh Lorestani, Soheil Sobhanardakani, Atefeh Chamani,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Monitoring and remediation of metal contaminants in aquatic ecosystems is of particular importance to estimate, control, and reduce the level of threats to alive creatures and humans. Therefore, this study was conducted to evaluate metal contamination of surface sediments and the ability to monitor and bioremediation of iron, lead, and copper by aerial and underground tissues of Typha Latifolia and Nasturtium microphyllum located along the aquatic ecosystem of the Lar River, Tehran, Iran in 2021.
Materials and Methods: In this descriptive study, after selecting four sampling sites, 48 plant samples and 12 sediment samples were collected. After preparation and acid digestion of the samples in the laboratory, the contents of the elements were determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, pollution index (PI), pollution load index (PLI), bioconcentration coefficient (BCF), bioaccumulation (BAF), and translocation factor (TF) were calculated. Statistical analyses of the results were performed using SPSS statistical software.
Results: The highest values of Fe, Pb, and Cu (mg/kg) in sediment samples were 11.8 ± 0.665, 0.915 ± 0.030, and 0.710 ± 0.026, respectively, and belonged to station 4; and in plant tissues 11.4 ± 1.25, 0.578 ± 0.180, and 0.298 ± 0.095, respectively, and were belonged to the roots of T. Latifolia. The PI values showed that the pollution of Fe, Pb, and Cu was "low" and the average PI values for the elements followed the descending order of Pb > Cu > Fe. The average values of PLI also vary from 0.003 to 0.006, indicating the quality conditions of "no pollution" in all the studied stations. On the other hand, T. Latifolia had a BCF > 1 and TF < 1 for Fe.
Conclusion: Based on the results obtained, it can be concluded that T. Latifolia is a suitable species for stabilizing Fe in sediments and could be used to monitor and remediate potentially toxic elements from polluted aquatic ecosystems.
 

Risk assessment of health and ecological some of heavy metals in lettuce, cabbage, and soil of Dezful, Ramhormoz, and Hamidiyeh farms
Zahra Moavi, Khoshnaz Payandeh, Mehrnosh Tadayoni,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Heavy metals are dangerous pollutants in the environment that accumulate in food. This research was conducted with the aim of evaluating the health risks and contamination of some heavy metals in lettuce and cabbage in the cities of Hamidieh, Dezful and Ramhormoz in Khuzestan province.
Materials and Methods: The sampling was completely random, with three repetitions, and 15 samples of each of the lettuce and cabbage vegetables grown in each region were prepared. Heavy metals were measured using the Perkin Elmer 4100 atomic absorption device. Heavy metal risk assessment was conducted using soil pollution indicators and health risk assessment method.
Results: The highest amount of metal in cabbage is related to zinc (5.84±0.15 mg/kg), while the lowest amounts of chromium metal in lettuce (0.11±0.005 mg/kg) was achieved. Based on the daily absorption of heavy metals in lettuce and cabbage products, the results showed that the highest hazard index (HQ) values, ​​related to lead metal in cabbage for children and adults, were 3.9376 and 3.4253, respectively, compared to other heavy metals. The highest value of the carcinogenicity index in children was 0.0133 for cabbage consumption. The carcinogenic index of chromium metal in lettuce and cabbage products had the lowest values (0.0003 and 0.0004). Regarding the metal enrichment factor, lead, chromium, copper and cobalt were higher in the agricultural soils of Ramhormoz compared to other regions, while nickel and zinc were higher in the soils of Hamidiyeh than in Dezful and Ramhormoz. The soil index of accumulation of chromium, zinc and copper in the soil of Dezful agricultural fields was higher, whereas lead and cobalt were higher in Hamidiyeh soils than in Dezful and Ramhormoz. Additionally, nickel was higher in Ramhormoz agricultural fields.
Conclusion: According to the soil pollution indicators, cobalt metal played an important role in the soil pollution in Dezful, Hamidiyeh and Ramhormoz, while the metals lead, nickel, chromium, copper and zinc showed minimal pollution levels in the soil of the studied areas. The health risk assessment of soil heavy metals showed that the risk index for lead, nickel, chromium, copper, zinc and cobalt was lower than 1. Additionally, the carcinogenicity index of heavy metals for both adults and children was less than 10-4. The health risk assessment of heavy metals and their risk index showed that the consumption of lettuce and cabbage in these areas can lead to various health problems in people.
 

Investigating the physicochemical characteristics in edible oils produced by cold press and industrial methods in Sabzevar city
Ehsan Manavipour, Akbar Eslami, Abbas Shahsavani, Ahmad Alahabadi, Reza Saeedi, Fatemeh Shokri Dariyan, Mehrnoosh Abtahi,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: In today's society, preparing healthy food has become challenging due to the variety of food production methods. Oil is produced in several ways in our country. In the cold pressing method, there is insufficient monitoring of the manufactured product. The aim of the present study is to investigate the physicochemical characteristics and the levels of heavy metals of industrial oil compared to cold-pressed oil.
Materials and Methods: In this research, 54 samples of sunflower, sesame, and canola oil produced by both cold pressing and industrial refiningmethods were prepared. Their physicochemical characteristics, including refractive index, acid value, iodine value, saponification value, peroxide value, anisidine value, as well as the concentrations of lead, iron, arsenic and copper were determined. Additionally, the effect of storage time on these characteristics was investigated.
Results: The Iodine number showed the highest deviation from the standard (61%), with an average of 136.70 gI/100g for the cold-pressed oil and 134.48 gI/100g for industrially refined oiland. The average value of the physicochemical characteristics, except for the saponification value, were higher in the cold-pressed oil samples  compared to the industrially refined oil samples, but the observed difference was not statistically significant. An investigation into the effect of storage time on physicochemical properties revealed a significant increase in peroxide value (p<0.01) and anisidine (p <0.05) in both oil groups over a two-month period. The average concentration of arsenic, lead, iron and copper in the studied oils was 0.03, 0.78, 0.05 and 0.05 mg/kgoil, respectively. A deviation from the standard was observed only in one sample of cold-pressed sunflower oil, with an arsenic concentration of 0.11 mg/kgoil).
Conclusion: Based on the obtained results, the refined industrial oils exhibited more favorable chemical characteristics and stability.  It is suggested that cold-pressed oils should be consumed within a short period of time. For frying purposes, refined industrial oils are preferable.
 

Evaluation of the quality of unconventional water (wastewater treatment plant effluent) of Pakdasht city for Cucurbits irrigating in 2022
Abbas Khazaee, Mehrnoosh Abtahi, Mahsa Jahangiri-Rad, Fatemeh Shokri-Daryan, Mohammad Rafiee,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Identifying the quality of non-conventional waters and exploring their optimal utilization are fundamental measures for maintaining public health. This study aims to investigate the effluent quality of the irrigation canals in Pakdasht farms.
Materials and Methods: In this cross-sectional descriptive study, 120 samples were collected from 6 irrigation canals in Pakdasht fields over a period of 5 months. The physicochemical and microbial characteristics of the canal effluents were determined based on the standard methods of water and wastewater tests. The concentration of heavy metals was measured using an ICP device. To determine the possibility of using the effluent of Pakdasht canals for agricultural purposes, the Environmental Protection Organization of Iran and FAO standards were used.
Results: The average concentrations of COD, BOD5, TSS, TDS, NO3-, SO4-2, PO4-3 parameters were 259, 125, 105, 697, 4.5, 94.4, 13.5 mg/L. Additionally, the average number of total and fecal coliforms in the effluent of the canals exceeded the standard values set by IRNDOE and FAO. The mean pH was 6.97, the electrical conductivity (EC) was 1014 μm/cm, and the turbidity was 76.2 NTU. The detected concentrations of heavy metals were awithin the following ranges: Cr (0.025-0.045 mg/L), Cd (0.0006-0.001 mg/L), Pb (0.0006-0.001 mg/L), Co (0.038-0.059 mg/L), and Ni (0.05-0.06 mg/L), which were roughly lower than the suggested standards. However, both HEI and WWQI indices confirmed that the water was unsuitable for agricultural irrigation.
Conclusion: Based on the comparison of the results of the parameters measured in this study with the environmental and FAO standards, the effluent from the irrigation canals of Pakdasht city is deemed unsuitable for the irrigation of warm-season crops but suitable for fodder and industrial crops.
 

Investigation of heavy metal concentrations in agricultural topsoil of Miandoab landfill area
Nader Abbasi, Mohsen Mohammadi Galangash,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: Heavy metals are regarded as serious contaminants due to their toxicity, persistence in natural conditions, and ability to enter and accumulate (bioaccumulation and biomagnification) in food chains. The aim of this study was to investigate the concentrations of the heavy metals Pb, Cd, Cu, Zn, Cr, Fe and Ni in surface agricultural soils of the Miandoab landfill area.
Materials and Methods: In this study, 57 soil samples were collected from a depth of 0-20 cm. After preparing and digesting in the laboratory, the samples were analyzed using a inductively coupled plasma spectrometer (ICP-OES). The Ecological Risk Potential Index (EPRI), Earth Accumulation Index (Igeo), Principal Components Test (PCA) Pearson's Correlation, Cluster Analysis, and One-T-test were utilized. Statistical processing was conducted using SPSS software.
Results: According to the results of the single T-test, the average concentrations of Pb, Cd, Cu, Zn, Cr, Ni did not significantly differ from their background concentration in the soil (p≥0.05). A significant difference was pbserved only for Fe (p<0.05), indicating a geological origin for this element. The EPRI was within the low-risk range, with an average value of 46.95. PCA revealed that the first factor was positively associated with Cr, Pb and Fe; the second factor with Zn and Cu; and the third factor with Cd. Cluster analysis showed that Fe was predominantly influenced by natural resources. According to the land accumulation index, all metals, except Cu, were classified non-polluted or slightly polluted at stations 2 and 4.
Conclusion: The origin of elements is related to both natural and human factors. Specifically, Cr, Pb and Cd are more likely to originate from man-made sources, while Fe primarily comes from natural sources. The decrease in the concentration of metals can be attributed to continuous and annual ploughing, inactivity of the landfill, biological absorption by crops, soil leaching and transporting to lower depths.
 

Contamination levels and human health risk assessment of mercury in some fish species from the Anzali International Wetland, Iran
Hassan Malvandi,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: The presence of toxic mercury in fish has caused global concern, as one of the main ways of humans are exposed to it is through fish consumption. Therefore, the main goal on this research was to determine the concentration of mercury in fish and evaluate the health risk to consumers.
Materials and Methods: Samples of pike, common perch, European perch, common carp and goldfish were collected from Anzali wetland. Mercury concentration was measured using a graphite furnace atomic absorption spectrometer. Differences in mercury concentration among the species and the comparison of mercury concentration with the standards were analyzed using one-way analysis of variance and one sample t-test, respectively.
Results: The average concentrations of mercury for pike, common perch, European perch, common carp and goldfish were 59.59, 67.55, 30.45, 9.84, and 10.44 µg/kg ww, respectively. The results showed significant differences in mercury concentrations among different species. The concentrations of mercury in all samples were below the permissible limits of international standards (300 and 500 µg/kg dw), and the HQ index values were less than 1. Therefore, the results indicated no potential risk to consumer health. Additionally, the consumption of European perch, common carp and goldfish is considered safe for sensitive people (children and pregnant women).
Conclusion: In general, there was no potential concern regarding mercury exposure from consuming the studied fish species.
 

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