Mohsen Samimi; Mohsen Shahriari Moghadam
Abstract
Background and Purpose: Phytoremediation stands out as one of the effective techniques for stabilizing, extracting, trapping, or detoxifying pollutants utilizing plants. This cost-effective and environmentally friendly approach leads to the revitalization and enhancement of vegetation, along with increased ...
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Background and Purpose: Phytoremediation stands out as one of the effective techniques for stabilizing, extracting, trapping, or detoxifying pollutants utilizing plants. This cost-effective and environmentally friendly approach leads to the revitalization and enhancement of vegetation, along with increased activity and growth of microorganisms. In this study, the species cultivated in the tailings of the lead and zinc mines of Ravanj were identified and assessed.Materials and Methods: Indigenous plants thriving in mineral tailings were isolated from the root portion. Random sampling of the identified soil and plant species was conducted. The accumulation of heavy metals (lead, zinc, manganese, chromium, copper, nickel, cadmium, and cobalt) in the soil, aerial organs, and roots of plants were quantified. Additionally, the bioconcentration factor of the aerial and root parts and the transfer factor were computed.Results: Among the heavy metals, cadmium, zinc, lead, and manganese displayed the highest accumulations in the leaves of Euphorbia macroclada (3.91±0.17 mg/kg), Verbascum speciosum (751.94±42.67 mg/kg), Acanthophyllum microcephalum (272.11±31.73 mg/kg), and Acanthophyllum microcephalum (594.59±9.76 mg/kg), respectively. Conversely, cobalt, chromium, copper, and nickel exhibited the most significant accumulations in the roots of Acantholimon hohenackeri (3.17±0.55 mg/kg), Acantholimon hohenakeri (20.16±2.28 mg/kg), Euphorbia macroclada (19.51±0.36 mg/kg), and Verbascum speciosum (17.56±0.90 mg/kg), respectively. Euphorbia macroclada demonstrated the highest bioconcentration in aerial parts and roots concerning cadmium metal (0.40). Furthermore, the Acantholimon hohenackeri plant exhibited the highest transfer factor (2.75), primarily associated with lead metal.Conclusion: Based on the findings of this study, the investigated species within the lead and zinc mines of Ravanj could serve as heavy metal-resistant ecotypes, contributing to the reduction of heavy metal mobility and bioavailability, thereby enhancing soil texture quality.
Fatah GHangi Zadeh; Abdolreza Karbassi; Naser Mehrdadi
Abstract
Background and Purpose: Benzene is one of the primary volatile organic compounds in urban air pollution. Beside its environmental implications, benzene poses various health risks to urban inhabitants. This study aimed to measure benzene levels at fuel stations (petrol pumps) in a specific area of Tehran ...
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Background and Purpose: Benzene is one of the primary volatile organic compounds in urban air pollution. Beside its environmental implications, benzene poses various health risks to urban inhabitants. This study aimed to measure benzene levels at fuel stations (petrol pumps) in a specific area of Tehran and model its dispersion to determine safe distances from the release point. Materials and Methods: The study, assessed benzene pollutant concentrations at 11 selected gas stations in Tehran’s 4th district over one-year using gas chromatography with a GC-FID flame ionization detector. Additionally, pollution dispersion modeling was conducted using the AEROMOD model, while the WISER software determined safe distances to aid emergency responses to chemical releases exceeding standard limits. Results: Benzene measurements at the selected stations indicated average emissions of 3.07 µg/ in spring, 3.50 µg/ in summer, 2.95 µg/ in autumn, and 2.35 µg/ in winter. Notably, levels surpassed standards at three locations, posing environmental and health risks to residents’ station 53 and the Takhti sampling area exhibited the highest and lowest benzene emissions, respectively, at 4.24 µg/ and 1.62 µg/ . The dispersion model revealed a maximum annual benzene concentration of approximately 7.89 µg/ , exceeding the standard limit. Safe distances determined by the WISER model ranged from 0.5 to 0.7 µg/ , extending between 50 and 300 meters from the sampling area. Conclusion: The study concludes that benzene emissions are higher in summer and lower in winter at the sampled locations. Distance from emission sources correlates with reduced benzene concentrations, thus minimizing population exposure. Safe areas were identified based on these findings. Given the health risks posed benzene emissions from gas stations, particularly in locations exceeding standard levels, targeted monitoring and control programs are imperative municipal areas and fuel stations.
Mahdi Saghafi; Ali Hajiabdollahi Mamaghani
Abstract
Background and purpose: The objective of this study is to simulate the release of pollutant gases from the chimney of the Tabriz thermal power plant to ascertain the concentration of these pollutants in the vicinity of the power plant. Materials and Methods: The dispersion of pollutants emitted ...
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Background and purpose: The objective of this study is to simulate the release of pollutant gases from the chimney of the Tabriz thermal power plant to ascertain the concentration of these pollutants in the vicinity of the power plant. Materials and Methods: The dispersion of pollutants emitted by the Tabriz thermal power plant is modeled using AERMOD software to analyze the concentrations of sulfur dioxide and nitrogen dioxide in nearby areas and neighboring cities within a 44.85 km square. The data utilized for this modeling encompass one-year meteorological records, emission source particulars, and geographical data. This modeling calculated the distribution pattern of pollution and pollutant concentrations on the ground surface near the Tabriz thermal power plant for intervals of 1, 3, and 24 hours, as well as the annual average. Results: The calculated results reveal that the maximum concentrations of nitrogen dioxide in the studied area, for intervals of 1, 3, and 24 hours, and the annual average are 957, 510, 135, and 5.21 micrograms per cubic meter, respectively. Similarly, the maximum concentrations of sulfur dioxide, for the same intervals, are 3998, 2208, 584, and 22.6 micrograms per cubic meter, respectively. Conclusion: The findings indicate that the maximum concentrations of sulfur dioxide and nitrogen dioxide in certain densely populated residential zones exceed the permissible limits set by environmental standards for specific criteria. Consequently, the health of residents near this power plant could be at risk.
Sadegh Hosseinniaee; Mohammad Jafari; Ali Tavili; Salman Zare
Abstract
Background and Purpose: Public concern over the effects of environmental pollutants on human health has intensified, prompting heightened scrutiny of toxic substances in human and animal diets over recent decades. This study aims to assess the impact of municipal waste compost on diminishing lead (Pb) ...
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Background and Purpose: Public concern over the effects of environmental pollutants on human health has intensified, prompting heightened scrutiny of toxic substances in human and animal diets over recent decades. This study aims to assess the impact of municipal waste compost on diminishing lead (Pb) concentrations in the diets and organs of grazing ruminants. Materials and Methods: In a controlled greenhouse experiment, compost was incorporated into naturally Pb-contaminated soil at four concentrations: 0%, 1%, 3%, and 5% (w/w). Stipa arabica plants were cultivated over six months. Subsequently, the Pb content in soil and plants was measured using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The daily Pb intake by cattle and sheep and its accumulation in their organs were then calculated using food chain models. These findings were evaluated against EU standards for animal product quality, focusing on animal health and human food safety. Results: The study identified the 1% compost addition as the most effective concentration, reducing Pb intake by 65% in cows and 60% in sheep, aligning with permissible health standards. Lead accumulation in the organs followed the pattern of kidneys > liver > muscle tissue, with a 64.77% decrease observed upon compost application. The Pb levels in all tested organs were lowered to safe thresholds concerning animal health. Moreover, Pb concentrations in meat fell below the standard limits, ensuring food safety for human consumption. Conclusion: Municipal waste compost, as an organic amendment, can significantly lower lead concentrations in the diets and tissues of grazing animals, ensuring levels remain within acceptable limits.
Abdoreza Pour Gholam Khabaz; Maryam Velayatzadeh
Abstract
Background and Purpose: This study aimed to investigate Pb pollution levels in the urban area of Shush City, utilizing dominant tree species as biological tracers.Materials and Methods: Sampling was conducted over one year, targeting two tree species, Albizia lebbeck and Eucalyptus microtheca, at four ...
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Background and Purpose: This study aimed to investigate Pb pollution levels in the urban area of Shush City, utilizing dominant tree species as biological tracers.Materials and Methods: Sampling was conducted over one year, targeting two tree species, Albizia lebbeck and Eucalyptus microtheca, at four locations with varying traffic levels in the urban area. Soil samples were collected from zero to 30 cm where the trees were situated, and leaves were gathered from 2 meters above the ground, covering four cardinal directions and performed in triplicate. 120 leaf and soil samples were transported to the laboratory for chemical analysis.Results: The highest average concentration of Pb in the winter of 2018 was recorded as 1183.2±4.6 mg/kg in the soil beneath the trees at the high-traffic station and 95.1±2.4 mg/kg in the unwashed leaves of Albizia lebbeck at the low-traffic station. During the summer season of 2019, Pb concentrations were 1056±2.7±3.3 mg/kg in the soil beneath the trees at the high-traffic station and 95.3±1.4 mg/kg in the unwashed leaves of the Albizia lebbeck tree at the low-traffic station.Conclusion: With bioaccumulation coefficients in all samples remaining below 1, it can be concluded that neither Albizia lebbeck nor Eucalyptus microtheca species possess a significant capacity for transferring heavy metals from the soil to their aerial organs. Additionally, they do not appear to absorb the available lead within their growth environment, making them unsuitable as bio-tracer plants
Hosein Aalidadi; Zahra Karimi; Aliakbar Dehghan; Hamed Mohammadi; Maryam Paydar
Abstract
Background and Purpose : Heavy metals are among the most critical contaminants in drinking water, owing to their stability and accumulation capability in living tissues and the food chain. Consequently, this study was conducted to determine the carcinogenic and non-carcinogenic risk assessment indices ...
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Background and Purpose : Heavy metals are among the most critical contaminants in drinking water, owing to their stability and accumulation capability in living tissues and the food chain. Consequently, this study was conducted to determine the carcinogenic and non-carcinogenic risk assessment indices for heavy metals in the water sources of Torbat-e Jam City in 2023.Materials and Methods : Samples were collected from 16 groundwater sources and the surrounding soil of Torbat-e Jam City during the summer and autumn of 2023. Concentrations of five heavy metals - arsenic, mercury, lead, cadmium, and copper - were measured using a Varian atomic absorption spectrometer. Finally, the health risk levels for three different groups were calculated using indices provided by the Environmental Protection Agency (EPA) of the United States.Results: The average concentrations of heavy metals in water during summer were as follows: arsenic: 0.0027 ± 0.0035 mg/L, mercury: 0.00019 ± 0.00035 mg/L, lead: 0.0011 ± 0.0023 mg/L, cadmium: 0.0002 ± 0.0002 mg/L, and copper: 0.0046 ± 0.0078 mg/L. In autumn, the concentrations were arsenic: 0.0082 ± 0.0081 mg/L, mercury: 0.0018 ± 0.0008 mg/L, lead: 0.0056 ± 0.0058 mg/L, cadmium: 0.00084 ± 0.00083 mg/L, and copper: 0.0091 ± 0.0068 mg/L. In soil, the concentrations were arsenic: 0.011 ± 0.053 mg/L, mercury: 0.0086 ± 0.0068 mg/L, lead: 0.131 ± 0.186 mg/L, cadmium: 0.0002 ± 0.00047 mg/L, and copper: 0.12 ± 0.24 mg/L. The study found the non-carcinogenic risk levels of the examined heavy metals to be low. However, the carcinogenic risk level for arsenic was very high in both seasons, for cadmium was moderate in autumn, and for the other elements, it was within the standard limits.Conclusion : Given the high carcinogenic risk of arsenic for women, men, and children in both summer and autumn, continuous monitoring of arsenic levels should be a priority for regulatory agencies.
Mojtaba G.Mahmoodlu; Tara Sotoudehnia
Abstract
Background and Purpose: Groundwater serves as the primary drinking water source in Golestan Province. Therefore, this study aims to assess the non-cancerous health risks associated with nitrate and fluoride in the province's drinking water sources. Materials and Methods: Physicochemical data from ...
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Background and Purpose: Groundwater serves as the primary drinking water source in Golestan Province. Therefore, this study aims to assess the non-cancerous health risks associated with nitrate and fluoride in the province's drinking water sources. Materials and Methods: Physicochemical data from 139 drinking water wells were obtained from the Golestan Province Water and Wastewater Company during the spring and autumn. Significant ion variations were analyzed, and factors influencing the chemistry of drinking water sources in Golestan Province were investigated. Non-carcinogenic health risks posed by nitrate and fluoride were assessed using two indicators provided by the United States Environmental Protection Agency. Results: The maximum nitrate concentration in certain Golestan Province cities exceeds the Iranian drinking water standards (1053) and the World Health Organization's limits. However, fluoride levels in most cities fall below the range stipulated by domestic and international standards. The nitrate risk factor for children in select cities exceeds one, while it remains below one for other age groups. Notably, Khan Bebin City exhibits the lowest nitrate risk factor among the province's cities. Additionally, risk factor values show a slight increase during the autumn season. Non-cancerous health risk assessments for fluoride in drinking water sources across Golestan Province during spring and autumn indicate risk values below one for all age groups, including infants, children, teenagers, and adults. Conclusion: The health risk assessments for nitrates and fluorides indicate that children in certain cities face a higher risk from nitrates than adults. Moreover, the low fluoride levels in the province's drinking water sources increase the likelihood of tooth decay.
Rahele Valizadeh Ardalan; Mitra Mohammadi; Mohammad Sadegh Bahadori
Abstract
Background and Purpose: Increasing population growth and technological advancements in cities inevitably result in rising noise pollution levels. The emergence of the coronavirus disease worldwide, including Iran, has significantly altered people's daily lives. This has presented a unique opportunity ...
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Background and Purpose: Increasing population growth and technological advancements in cities inevitably result in rising noise pollution levels. The emergence of the coronavirus disease worldwide, including Iran, has significantly altered people's daily lives. This has presented a unique opportunity to assess changes in sound levels. Therefore, this study aims to investigate sound level variations before the outbreak and during the COVID-19 restrictions at a pivotal intersection in Mashhad.Materials and Methods: The initial segment of this study examined the sound equivalent level in April 2018 and 2019 without considering any specific circumstances at the Shohada crossroad. In the second segment, employing SPSS22 software and the Wilcoxon test, we compared the alterations in various sound level indicators before the disease prevalence (April 2018) and during the restrictions (April 2019).Results: The results of the first part of the study revealed that the hourly equivalent sound level (Leq) in April 2018 and 2019 was 70.48 and 70.39 dB, respectively. The results of the second part indicated a significant difference between the two periods under investigation in terms of equivalent sound levels. The maximum and minimum sound equivalent levels (LMax, Lmin) reduction during the disease outbreak compared to the pre-outbreak period was 0.16 and 0.08 dB, respectively. Additionally, during the night curfew hours (21-03) in April 2019, the sound equivalent level decreased by 0.09 dB compared to 2018. Conclusion: The findings of this study demonstrate that the equivalent sound level at the Shohada crossroad in Mashhad exceeded national standards before the disease prevalence. However, noise pollution levels have decreased due to decreased economic activities during the outbreak and the associated restrictions. Nonetheless, the equivalent sound level still surpasses the established standards, indicating that noise pollution at the mentioned intersection persists. Further research is warranted on this subject, encompassing traffic modeling, noise pollution emission inventories, establishing links between land use patterns and noise pollution, and the influence of weather conditions on sound levels.