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Showing 71 results for Heavy Metals
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.
 

Ecological and human risk assessment of some heavy metals in the dust of elementary schools in selected areas of Mashhad city
Hassan Malvandi,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Dust particles in urban environments are often contaminated with heavy metals, posing significant health risks, particularly to children. Schools are one of the environments where children are exposed to dust particles. Therefore, the aim of this study was to determine the concentration of heavy metals in the dust collected from Mashhad schools and to assess the associated health risks.
Materials and Methods: Dust samples were collected from 27 schools in the fall of 2022 using a brush.  The values of various indices were estimated, including the geoaccumulation index (Igeo), contamination factor (CF), pollution load index (PLI), enrichment index (EF), potential ecological risk index (PERI), and health risk indices such as hazard quotient (HQ) and hazard index (HI).
Results: The average concentrations of cobalt (Co), iron (Fe), calcium (Ca), aluminum (Al), lead (Pb), and barium (Ba) were 9.63, 18538.58, 84017.79, 11270.42, 32.07 and 111.56 µg/g, respectively. The Igeo values ranged from -3.69 to 1.51, while the CF values ranged from 0.16 to 4.26. The results of the pollution indices indicated that most of the studied elements were at the first level of pollution, suggesting that the degree of pollution was negligible or low. Additionally, the HQ and HI values were both less than 1.
Conclusion: Overall, the concentrations of the studied elements were not a concern, remaining at uncontaminated levels, and there was no potential health risk associated with exposure to these elements.
 

Evaluation of risk and pollution load of heavy metals (Fe, Zn, Pb, Cd, Cu, Mn, and Mo) in surface soil of Al-Qasim city, Babylon governate, Iraq
Jawad Kadhim Noor, Atefeh Chamani, Ahmed Najm Abdallh Al-Mosawy, Narges Kargari,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: The pollution of trace elements in urban soil has attracted wide attention due to its detrimental environmental and health effects. Therefore, this research was conducted to evaluate of the content, pollution levels, and health risks associated with trace elements (Fe, Zn, Pb, Cd, Cu, Mn, and Mo) in the surface soil of Al-Qasim City in Babylon Governate in 2024.
Materials and Methods: This descriptive cross-sectional study involved, a total of 50 surface soil samples from a depth of 0-20 cm. The elemental content of the samples was determined using inductively coupled plasma optical spectroscopy (ICP-OES). Additionally,, the enrichment factor (EF), pollution index (PI), pollution load index (PLI), hazard index (HI), and carcinogenic risk (CR) were calculated. Statistical data analyses were done using SPSS software. 
Results: The average concentrations of Fe, Zn, Cd, Cu, Mn, and Mo in the soil were 27240, 62.7, 0.302, 33.8, 570 and 0.999 mg/kg, respectively. The highest average concentrations of Fe (30,331 mg/kg), Cu (37.3 mg/kg), Mn (639 mg/kg), and Mo (1.08 mg/kg) were found in downtown areasm whilefor the highest concentrations of Zn (65.3 mg/kg) and Cd (0.332 mg/kg) were observed in rural and midtown areas.
Conclusion: The results of this research demonstrate the impact of urban activities—such astraffic, industry, and agriculture—on the trace element pollution in the soil of Al-Qasim City. Therefore, regular monitoring of trace element concentrations and identification of their pollution sources are recommended to reduce and manage associated environmental and health risks.
 

Chemical speciation and bioavailability of potentially toxic elements in agricultural soils (case study: south of Hamedan province)
Iraj Asadi, Mehrdad Cheraghi, Bahareh Lorestani, Hajar Merrikhpour, Soheil Sobhanardakani,
Volume 17, Issue 4 (3-2025)
Abstract
Background and Objective: Evaluating the chemical speciation and bioavailability of heavy metals, along with identifying the effective parameters influencing their bioavailability, plays a key role in soil management and the improvement of agricultural lands. Therefore, this research was conducted to determine the origin, chemical speciation, and bioavailability of potentially toxic elements (PTEs) in the agricultural soils of the southern cities of Hamedan province.
Materials and Methods: In this study, 90 surface soil samples were randomly collected from a depth of 0–20 cm in agricultural lands. After preparing the samples in the laboratory, the elemental content was measured using an atomic absorption device. Texture characteristics, acidity (pH), salinity (EC), calcium carbonate content, organic matter, and exchangeable cations were determined using methods proposed by the Environmental Protection Organization. The relationships between the bioavailability of heavy metals and these characteristics were investigated using Spearman's correlation test.
Results: The average concentrations of manganese, cadmium, iron, cobalt, chromium, copper, nickel, antimony, and arsenic in the three studied cities were 267.63, 0.19, 4.20, 20.65, 90.49, 35.86, 70.84, 3.78, and 17.82 mg/kg, respectively. Sequential extraction results showed that manganese, copper, and nickel had the highest bioavailability, with concentrations of 6.76, 2.91, and 3.77 mg/kg, respectively. More than 70% of the bonds between heavy metals and soil were in resistant and residual fractions, indicating that heavy metals in the soil have a natural background.
Conclusion: The bioavailability of heavy metals in the soil environment is low, suggesting minimal potential for these metals to enter water, soil, and crops, and thus does not pose significant concern.
 

Study of heavy metals concentration in liver, gills and muscles tissues of Lutjanus ehrenbergii from the Hengam Island, Persian Gulf
Mohammad Hossein Ghaderi, Azad Teimori, Majid Askari Hesni,
Volume 18, Issue 2 (9-2025)
Abstract
Background and Objective: Given the negative effects of heavy metals and their transmission to humans through the food chain, the present study was conducted to assess the concentration of heavy metals—including Fe, Zn, Cd, Pb, Ba, Ni, Cu, V, and As—in the gill, liver, and muscle tissues of the commercial fish Lutjanus ehrenbergii.
Material and Methods: Thirty fish were collected from coral habitats around Hengam Island in 2022 using nets or hooks. After identification and bioassay, the liver, gill, and muscle tissues were dissected from each specimen and analyzed for heavy metal concentrations via ICP-MS.
Results: Biometric analysis showed the average standard length, total length, and weight of the studied fish to be 23.3 ± 1.4 cm, 27.8 ± 2.7 cm, and 470.3 ± 18.9 g, respectively. Among the studied elements, Fe had the highest mean concentration in the gill (327.41 µg/g) and liver (136.10 µg/g) tissues. In muscle tissue, Zn showed the highest mean concentration (2.68 µg/g), while Ni showed the lowest accumulation. The mean Pb concentrations detected in the gill, liver, and muscle tissues were 1.38, 1.35, and 0.46 µg/g, respectively.
Conclusion: The Pb concentration in the muscle, which is the main nutritional tissue, was 0.46 µg/g. This value is higher than the limits set by international standards such as the WHO. Therefore, from a health perspective, it is not recommended to consume commercial fish contaminated with heavy metals. While continuous monitoring can provide information on contamination status, the consumption of Lutjanus ehrenbergii caught around Hengam Island should be done with caution.
 

Assessment of carcinogenic and non-carcinogenic risk of heavy metals in edible vegetable oils from Sabzevar, Iran
Hadi Niknejad, Ehsan Manavipour, Musa Cheshmi, Vajihe Hasanzadeh, Roghayeh Abedi Sarvestani, Fatemeh Ahmadi, Mehrnoosh Abtahi,
Volume 18, Issue 2 (9-2025)
Abstract
Background and Objective: Heavy metal contamination in vegetable oils is a major food safety concern due to its potential adverse effects on public health. This study aimed to measure the concentrations of heavy metals (As, Pb, Cu, and Fe) in various types of vegetable oils and to assess the associated health risks from human consumption.
Materials and Methods: In this study, 72 samples of vegetable oils—including sesame, sunflower, and rapeseed—were systematically collected from markets in Sabzevar. The oil samples were accurately weighed and digested using a mixture of nitric acid, sulfuric acid, and hydrogen peroxide. The resulting digested solutions were filtered and analyzed for Pb, As, Cu, and Fe concentrations using microwave plasma atomic emission spectrometry (MP-AES). All procedures were performed in triplicate, following national Iranian standards. To accurately evaluate health risks, the hazard quotient (HQ) for non-carcinogenic effects and the lifetime cancer risk (LTCR) were calculated using Monte Carlo simulation (MCS). A daily intake of 0.227 kg of vegetable oils was assumed, based on national dietary data, to estimate chronic exposure.
Results: The results showed that the highest levels of heavy metals in vegetable oils were as follows: Pb (0.058 mg/kg) in sesame oil, As (0.090 mg/kg) in sunflower oil, and Cu and Fe (0.143 mg/kg and 0.847 mg/kg, respectively) in rapeseed oil. The Target Hazard Quotient (THQ) values for Pb (THQ = 0.146), Cu (THQ = 0.022), and Fe (THQ = 0.01) were within the safe range. However, the THQ for As (THQ = 1.905) was found to be significantly elevated. The cancer risk assessment indicated that the consumption of these oils is generally within the acceptable risk range, but the risk associated with As was estimated to be approximately 100 times higher than that of Pb.
Conclusion: The results of this study suggest that, although the carcinogenic risk associated with vegetable oil consumption is low, continuous monitoring of these products—particularly for heavy metal contaminants—is essential to ensure consumer safety.
 

Investigating the accumulation of heavy metals in the bartail flathead fish (Platycephalus indicus) of Makkoran coasts
Mahin Gholami, Seraj Bita, Mostafa Ghaffari,
Volume 18, Issue 3 (12-2025)
Abstract
Background and Objective: Heavy metals have become a major environmental and public health concern due to their entry into marine ecosystems and accumulation in aquatic organisms. Therefore, the present study aimed to investigate the accumulation of cadmium, lead, chromium, zinc, copper, and nickel in the liver, gills, and muscle tissues of Platycephalus indicus.
Materials and Methods: Thirty-six fish were collected from the fish landing site on the Makoran coast and transported to the laboratory in ice-filled containers. After drying and digesting the samples with nitric acid, the concentrations of heavy metals were measured using an atomic absorption spectrometer. Two-way ANOVA and Tukey’s post hoc test in SPSS software were used to compare the concentrations of the analyzed heavy metals.
Results: The results showed that, except for lead, the highest concentrations of the studied metals were recorded in the liver tissue. A significant difference in zinc concentration was observed between the Chabahar, Gowatr, and Konarak regions and the other sampling sites (p < 0.05). Among the analyzed metals, zinc had the highest concentration, with an average of 27.66 mg/kg, while cadmium had the lowest, with an average of 0.029 mg/kg. Health risk analysis indicated that, except for lead and nickel in fish caught from Chabahar, the concentrations of the other metals in Platycephalus indicus were below the permissible limits recommended by international standards, including WHO, FDA, UKMAFF, NHMRC, and FAO.
Conclusion: According to the results, the liver serves as the primary site of heavy metal accumulation in Platycephalus indicus. The findings also indicate that lead and nickel concentrations in certain areas exceed permissible limits, potentially posing a risk to consumer health. These results underscore the need for enhanced monitoring of marine pollutants along the Makoran coastline.
 

Assessment of exposure of pregnant mothers in Arak city to heavy metals lead, cadmium, and mercury and its effect on birth weight and infant growth relative to gestational age
Behrooz Karimi, Maryam Shokarpour, Nazila Najdi, Katayoun Vakilian, Mohammad Javad Ghanadzadeh, Marjan Mahlouji,
Volume 18, Issue 3 (12-2025)
Abstract
Background and Objective: Heavy metals such as lead, cadmium, and mercury, due to their bio-accumulative properties, pose significant risks to maternal and fetal health. This study investigated the association between exposure to these metals among pregnant women in Arak and adverse birth outcomes, including infant birth weight and growth status.
Materials and Methods: A cross-sectional study was conducted among 235 pregnant women residing in Arak in 2024. Inclusion criteria were residence in Arak, age under 18 years, and absence of psychological or cognitive disorders; exclusion criteria included migration or leaving the city during the study period. Participants were evaluated at two intervals: the first and second halves of pregnancy. Demographic and clinical data were collected, and urinary concentrations of lead, cadmium, and mercury were measured. The effects of metal exposure on birth weight and growth status, including small-for-gestational-age (SGA) and large-for-gestational-age (LGA), were assessed using linear and logistic regression models adjusted for maternal age, education, and body mass index.
Results: The mean birth weight was 3,232.5 g; 10.64%of infants were classified as SGA, and 3.40%as LGA. The mean urinary concentrations of lead, mercury, and cadmium were 0.48±0.84 μg/L, 2.64 ±1.40 μg/L, and 0.36±0.80 μg/L, respectively. Cadmium exposure during both phases of pregnancy was associated with reduced birth weight, while lead showed negative effects during late pregnancy. In early pregnancy, lead (OR =1.026) and cadmium (OR = 1.044) were associated with an increased risk of SGA, whereas mercury (OR = 1.042) was associated with LGA.
Conclusion: Cadmium and lead exposure reduce birth weight and increase risks of SGA and LGA, highlighting the need to minimize maternal exposure to heavy metals.
 

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