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Assessment of potentially toxic elements pollution in soils and plant leaves along the high-traffic highway zones in Tehran, Iran Texte intégral
2024
Mahdieh Hosseinzadeh | Hamid Toranjzar | Abbas Ahmadi | Nourollah Abdi | Javad Varvani
The accumulation of potentially toxic elements (PTEs) in roadside soils and plant leaves due to vehicular emissions presents significant environmental and public health risks, particularly in densely populated urban areas. This study evaluated the concentrations of five PTEs—copper (Cu), lead (Pb), nickel (Ni), cadmium (Cd), and zinc (Zn)—in soils and leaves of three urban plant species (Pine, Cypress, and Mulberry) across six highways in Tehran, Iran, categorized into high, medium, and low-traffic zones. Soil samples were collected at a depth of 0–30 cm, and leaf samples were obtained from the canopy's outer sections. Samples were digested with aqua regia (soil) and nitric-hydrochloric acid (leaves) and analyzed using atomic absorption spectrophotometry. Pollution indices, including Pollution Load Index (PLI), Transfer Factor (TF), and Bioaccumulation Factor (BCF), were applied to assess contamination levels and metal mobility.The results showed moderate pollution levels across high-traffic zones (PLI = 3.94), with cadmium (Cd) contributing the most significant ecological risk (RI = 154.50). Transfer Factor (TF) analysis revealed high bioavailability for zinc (TF = 0.78) and lead (TF = 0.81), while cadmium exhibited limited uptake by plants (TF < 0.004). Bioaccumulation Factor (BCF) calculations indicated Pine and Cypress species had higher potential for metal uptake, with BCF values exceeding 1 for zinc and lead in high-traffic areas, whereas Mulberry demonstrated relatively lower accumulation. Despite a normalized NIPI index value of 1, the enrichment factor (EF) for zinc (EF = 98.04) underscores significant anthropogenic contributions, particularly from non-exhaust vehicular emissions. These findings highlight the need for ongoing monitoring, effective traffic management, and remediation strategies to address heavy metal pollution in urban environments.
Afficher plus [+] Moins [-]Evaluation of blood parameters changes of mice exposed to long-term Wi-Fi waves as a major environmental pollutant Texte intégral
2024
Hamed Akbari | Lobat Taghavi | Seyed Kamal Eshagh Hossaini | Mohammad Gholami-Fesharaki | Seyed Alireza Hajiseyed Mirzahosseini
As the world entered the industrial era, the nature of environmental threats and dangers posed by technology also have gone through fundamental changes. One of these environmental pollutants is the propagation of waves with different wavelengths in the environment. In this study, we aimed to investigate the effect of 2.45 GHz microwaves on blood biomarkers of mice. In this study, 80 immature male BALB/c mice were used. According to the inclusion criteria, 72 mice were included in the study. Mice were divided into two groups (control group=24 mice, exposed group=48 mice). Exposed groups were divided into two subgroups of 24 (groups A and B). Subgroup A was exposed to a simple modem without antenna and subgroup B was exposed to a modem with two antennas. In the first phase of the study, mice were exposed daily for 60 minutes for 90 days and in the second phase for 8 hours daily for 90 days. Blood samples were taken on days 90 and 180. Data analysis was done by SPSS software version 25 (P value<0.05). This study shows that blood cells are affected by long-term exposure to Wi-Fi waves by decrease in number and volume. Furthermore, no significant difference was observed between the blood parameters of the two groups exposed to different modems which vary in the number of antennas. The results showed that the highest effect of Wi-Fi waves was on the following blood factors, respectively PLT, RBC, HCT, HGB, and WBC.
Afficher plus [+] Moins [-]Assessment of noise pollution in sports halls in Lahijan, Iran Texte intégral
2024
Maryam Hajesmaeiliyan | Ali Fahimi Nezhad | Bagher Morsal
The aim of this study was to assess the noise pollution of sports facilities in multi-purpose halls in Lahijan city, Iran. This research was of applied type. Through networking, 16 halls were randomly selected in four zones of the city and data were collected in the field. The sound level in the clubs was measured at level A and as an equivalent level by a portable device and Decibel X 2019 and compared with the sound standard (OSHA-90 dBA). The measurements were performed in triplicate and repeated three times. The calculated parameters included sound pressure level (SPL), average sound level ((LP) ̅), continuous sound equivalent level (Leq) and individual daily dose LAEp,d. The results showed that the lowest sound pressure level was 73.9 dB in the northern zone and in the first turn. The highest sound pressure level in the western zone was 97.7 dB. As the time changed from early morning to night, the average sound pressure level increased, highlighting the direct relationship between the sound pressure level and the measurement time. The average sound level in the western zone was higher than in other zones, and the average sound level in the southern zone was lower than in other zones. In both zones, the gyms were of the shed type, which could not establish a relationship between the structural form and the sound level. All the studied halls had levels higher than the standards for recreation centers and parks, as well as the standards of the United States Environmental Protection Agency (EPA). However, all of the gyms met other standards such as ACGIH, NIOSH and OSHA standards related to occupational health. Finally, there was a relationship between the urban location of sports halls and the sound level, such that halls located in the northern and western zones (the more affluent part of the city) had higher sound levels; in contrast, those located in the southern and eastern zones (poorer areas of the city) had lower sound levels.
Afficher plus [+] Moins [-]Determining the dynamics of land use changes in a long-term time span in Erzurum, Turkey Texte intégral
2024
Nazila Alaei | Memet Salih Bayraktutan | Raoof Mostafazadeh
Land use change shapes landscapes and is crucial for effective natural resource management, requiring a deep understanding of its trends for informed land management. The study utilized Landsat TM and Sentinel-2 satellite images spanning 1994 to 2023 to generate a 30-year land use change map of Erzurum. After processing of satellite images in ENVI, the Maximum Likelihood Algorithm used for classification and the Kappa coefficient used for reliability of results. Single and dynamic land use change indices used to assss the changes in LULC classes. The results indicated appropriate accuracy in the classified maps with a Kappa coefficient exceeding 0.75. The results revealed that the most significant land use changes in the Erzurum region were related to the conversion of rangeland to agricultural land. Over the period from 1994 to 2023, there was a notable increase in agricultural land use in Erzurum, contrasting with negative trends in waterbodies and garden areas. Rangeland experienced the most significant decline, decreasing by 19.22%, while agricultural land increased by 18%. indicating the highest growth among land use categories. According to the Single Dynamic Index, Bare Ground exhibited a change of +0.32%, while tree lands displayed a notably high dynamic degree of +0.31%. The significant expansion of agricultural land in Erzurum is primarily driven by agriculture being the main livelihood for local communities. This shift from rangelands highlights the strain on natural resources, necessitating careful management planning to balance agricultural expansion with environmental conservation concerns.
Afficher plus [+] Moins [-]Investigating the Efficiency of Lightweight Expanded Clay Aggregate (LECA) in Wastewater Treatment of Dairy Industry Texte intégral
2024
Hooman Bahmanpour | Reza Habashi | Seyed Mohammad Hosseini
Lightweight expanded clay aggregate due to its physical and chemical properties; it can increase the process of adsorption and ion exchange. In this study, the efficiency 2 types of Lightweight Expanded Clay Aggregate in reducing the amount of COD, BOD, TSS, nitrate and phosphate in dairy industry wastewater were investigated and the impact of different factors such as adsorbent dosage, mixing speed and mixing time were studied. The results showed that the efficiency of COD reduction of wastewater after touch with the granular type after 20 h is 65.9%. TSS and BOD have also been greatly reduced. Also the use of powder type, the highest removal efficiency was 31.81%, mixing speed 100 rpm, mixing time 20h, and adsorbent dosage 10 gr/l in addition; increasing the rate of mixing speed increases the amount of nitrate absorption. The most effective nitrate removal is 63.87% which was at mixed speed 200 rpm and absorbent dose 4 g/l. Results show that, the mixing speed has little effect on the absorption of phosphate. So, after 30 minutes, even with increasing mixing speed for doses 2 & 4 g/l, the reduction efficiency also decreases the change in absorbent dose from 1 g/l to 4 g/l was virtually unaffected. Increased mixing speed is due to better distribution of nitrate and phosphate molecules in the solution and their contact with adsorbent increased the absorption rate. According to the results, the LECA granular has more ability to remove the COD.
Afficher plus [+] Moins [-]The Concentration of Heavy Metals in Precipitated Particles on the Leaves of Street Side Trees in the Urban Environments (Tehranâ Iran) Texte intégral
2024
Sara Abbasi | Habib Ali Mohammadian | Seyed Mohsen Hosseini | Nematollah Khorasani | Abd Al-Reza Karbasi | Atekeh Aslani
ABSTRACT: The preset study investigated heavy metals located on the leaves of street side trees in crowded areas of Tehran in order to evaluate the metal pollution caused by cars. Contamination factor, Index of geo-accumulation, enrichment factor, modified degree of contamination, and Pollution load index were used to describe the pollution of the environment and probable sources of metal emissions. The potential ecological risk of exposure to metals in the areas was measured. Leaves are useful and low-cost collectors of aerosols which are produced by transportation. According to the results of the present study, Pb, Cu, Cd, Co, Ni and Zn elements are the main pollutants within the study area; Cr and Hg, also, turned out to produce pollution in the environment. Pb and Cr have probably been emitted from depreciation of vehicles and corrosion of parts and industries; probable origins of Zn and Cu are the industrial combustion sources and alloys of automobile parts. Mn is emitted from anthropogenic sources and further studies are required to identify its emission sources. Mo and V are probably the result of natural sources. The origin of Al, Co and Hg is a combination of natural and man-made sources, with high proportion for man-made activities. Due to high concentrations of Hg and Cr in areas outside and inside the city, further studies are required to find the source of origin of Hg and Cr elements. The ecologic risk of Pb, Cd and Cu was higher in different study areas. The risk of exposure to heavy metals in high density areas, and especially in Geisha, turned out to be high. Traffic of old cars and the traffic flow are effective in the pollution changes in different areas, and decrease in wind speed and direction causes pollution escalation in central areas of Tehran, compared to Western and Northern areas.
Afficher plus [+] Moins [-]A Photographic Investigation of Tehran’s Light Pollution from North and East Directions Texte intégral
2024
Seyed Hamed Mirzakhalil | Sepehr Arbabi Bidgoli
Tehran is the most affected town by light pollution in Iran. In this study, the role of the regional topography in the distribution of light pollution in Tehran was evaluated using digital images recording and analyzing the obtained images from Tehran sky-glow by East and South in standard image-processing Software. The scale of Tehran's glowing =dome as measured by 17 mag/arc sec2 or 0.017 cd/m2 by South, and 18.7 (mag/arc sec2) or 0.0035 cd/m2 by East. Considering the approximately equal distance of the two viewpoints from the center of Tehran city, the calculated scale by South is 1.36 times larger than the amount from the East point.
Afficher plus [+] Moins [-]The assessment of efficiency of saponin as bio-surfactant in removal of nickel and vanadium from soil contaminated by petroleum, Case study: Ahwaz oil pumping unit Texte intégral
2024
Behnoush Khoshmanesh | Rasoul Ghadami | Ali Akbar Ghafourinejad
This study aims to evaluate efficiency of saponin, a bio-surfactant, in removal of heavy metals like nickel and vanadium from the soils which are smeared by crude oil and it was conducted according to properties of soils locating within Shahid Chamran oil Pump Station in 2016. For this purpose, after conducting primary studies and in order to determine pilot conditions of test, soil properties were initially studied in this zone and then 5 sampling stations were selected. Parameters of nickel and vanadium were measured along with the TPHs and pH. The studied phases included three variables of temperatures within ranges of (15, 25, 35°C), pH range (6, 7, 8) and concentration of oil compounds within ranges of 10000 and 30000ppm. The findings from assessment on efficiency of removal of heavy metals showed that the conditions with variables of temperature (35°C) and pH (about 9) included the best efficiency of removal of nickel and vanadium. Under concentration 10000ppm, the efficiency for removal of nickel shows rate of 42.98% at constrained mode for removal of nickel and 32.46% to efficiency for removal vanadium. In concentration 30000ppm, rate of efficiency for removal of nickel was 44.34% and also yield of 35.24% for removal of vanadium. This indicates by rising of concentration in oil compounds, the rate of efficiency increased in efficiency of soil washing.
Afficher plus [+] Moins [-]Management of Seawater Intrusion in Coastal Aquifers of Caspian Sea Texte intégral
2024
Mehdi Nezhadnaderi
As result of density difference between seawater and fresh water in coastal aquifers, a transition zone between two fluids is formed. A wedge of saltwater can be entered in coastal areas to the aquifer. Seawater intrusion rate and extent of transition zone depends on several factors including: changes in sea level, aquifer characteristics, hydrologic conditions of upstream, discharging from the aquifer, tidal and seasonal fluctuations of sea water. In this paper height of interface between seawater and freshwater in Mazandaran coastal aquifers is calculated by relationships that have been used in previous researches. Then Babolâ Amol aquifer has reviewed by using of existing data in Water Company of Mazandaran and past researches. According to the available information, the development of exploitation of three zones (Alashroud to Haraz, Haraz to Babolroud and Babolroud to Talar river in Amol- Babol aquifer in south of Caspian Sea) for distances less than 2000 m to sea is possible in the Haraz to Alash river. The total amount of water from this study to can be discharged in the three regions is 505 million cubic meters, based on available data. According to statistics, 458 million cubic meters of these three areas are allowed to be discharged. Therefore, taking into account the withdrawal of unallowable wells, it can be assumed that the saltwater intrusion has more than 2000 meters to the coast. The results of this study are based on the hydrodynamic parameters of the aquifer for the past 9 years and seawater intrusion may be aggravated by climate change and hydrodynamic parameters change of in this aquifer. Therefore, it is necessary to carefully study hydrodynamic parameters of this aquifer.
Afficher plus [+] Moins [-]Studying the Hinosan toxin leak into underground water Studying the Hinosan toxin leak into underground water resources using GC-ECD and its elimination by active carbon Texte intégral
2024
Majid Saghi | Mohammad Hosein Bigtan | Ali Arasteh Nodeh | Atena Nozari
Contamination of water resources by pesticide toxins is considered as one of environmental issues which is because of plant pest diversity and subsequently use of various toxicants. In previous decades all over the world, the usage of organophosphorus toxins in order to preservation of agriculture products expanded. In Gilan province (Iran) there are numerous agriculture lands and gardens which are sprayed intermittently and since drinking water of the region residents is rather supplied by underground waters, then penetration of toxicants into the wells is possible. For this reason pesticide toxicants use could be a treat for drinking water supplying resources of this state. In the paper, samples of water from ten wells were collected and for measuring the quantities of toxicants, experiments were carried out during 4 seasons of year. Toxicant residues in samples were analyzed according to Gas ChromatographyâElectron Capture Detector (GC-ECD) method. Due to phosphorous toxicant analyze results; it is revealed that in some cases precipitation amount has a great effect on toxicant concentration inside well water because of leaching higher layers. Also it is indicated that clay presence in soil due to toxicant holding and rain or flood occurrence cause to decrease and increase toxicant leak into the underground water respectively. Finally in order to Hinosan toxicant removal from water resources, active carbon has been utilized. The results indicated that adsorption by active carbon was of Langmuir type and this adsorbent effective cause to eliminate Hinosan toxin from water resources.
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