Showing 771 results for Type of Study: Research
Ali Asgari, Soheil Sobhanardakani, Mehrdad Cheraghi, Bahareh Lorestani, Maryam Kiani Sadr,
Volume 18, Issue 4 (3-2026)
Abstract
Background and Objective: Street dust, as a significant non-point source of PTEs contamination, is one of the primary pathways through which human can be exposed to environmental pollutants. Therefore, this study was performed to assess the pollution and health risk of As, Cd, Co, Pb, and V in street dust in Kermanshah in 2023.
Materials and Methods: A total of 48 dust samples were collected from 16 sites. After sample digestion, the contents of the elements were determined using ICP-OES. Additionally, the enrichment factor (EF), integrated pollution index (IPI), and Nemerow integrated pollution index (NIPI) were calculated. The carcinogenic and non-carcinogenic risks from exposure to contaminated dust were estimated.
Results: The highest mean contents of As, Cd, and Co, and V with 7.28, 0.729, 9.02, and 8.78 mg/kg, respectively, were belonged to the industrial regions and for Pb with 101 mg/kg was recorded for the commercial areas, reflecting the impact of human inputs, especially from industrial and traffic sources. The EF values indicated that "no" to "severe" enrichment level in the study area. Also, the average values of IPI, indicating the "low" to "high" pollution conditions entire the sampling sites. The mean NIPI values ranged from 1.17 to 1.68, indicating "low" pollution conditions in the study area. The mean average values of HI for children and adults were categorized as "severe risk" and "low risk", respectively. However, the mean TCR values for citizens indicated high carcinogenic risk.
Conclusion: The results indicated that As and Pb had the highest contribution to cumulative health risks for both age groups; therefore, the control of emission sources of these elements, including fossil fuel combustion and traffic and also regular monitoring of street dusts especially in the regions with heavy pollution level are recommended.
Sadegh Kazemi, Fatemeh Rezaei, Kimia Nazarzadeh, Moradali Zareipour,
Volume 18, Issue 4 (3-2026)
Abstract
Background and Objective: Microplastic pollution is recognized as a major environmental threat, and individuals’ Knowledge, attitudes, and behaviors play a crucial role in its prevention. This study aimed to assess the levels of Knowledge, attitudes, and preventive behaviors of students at Khoy University of Medical Sciences toward microplastic pollution.
Materials and Methods: This cross-sectional study was conducted among students of Khoy University of Medical Sciences. All enrolled students (n = 550) were invited to participate using a voluntary census-based approach, of whom 400 completed the questionnaire. After excluding incomplete responses, data from 372 participants were included in the final analysis. Data were collected using a two-part questionnaire comprising demographic characteristics and a researcher-developed instrument assessing knowledge, attitude, and practice (KAP) regarding the prevention of microplastic pollution. Content validity was confirmed using the content validity ratio (CVR) and content validity index (CVI), and reliability was established through test–retest analysis (ICC = 0.78) and internal consistency (Cronbach’s alpha = 0.83–0.95). Data were analyzed using Pearson correlation and ordinal logistic regression in STATA version 15.
Results: The findings indicated that students’ levels of knowledge and preventive behaviors were predominantly moderate, while their attitudes toward preventing microplastic pollution were mostly positive. Ordinal logistic regression analysis showed that higher levels of knowledge (OR = 3.98, 95% CI = 1.91–8.28)and positive attitudes (OR = 14.96, 95% CI = 7.26–30.83) significantly increased the likelihood of engaging in preventive behaviors. In addition, younger age (OR = 9.41, 95% CI = 1.26–7.29), being married (OR = 3.03, 95% CI = 3.33–26.52), higher maternal educational level (OR = 2.99, 95% CI = 1.24–7.17), and father's employment status (OR = 1.67, 95% CI = 1.02–2.73) were identified as demographic factors effective in promoting preventive behaviors.
Conclusion: The results suggest that enhancing Knowledge and fostering positive attitudes considerably improve preventive behaviors against microplastic pollution among students. Therefore, implementing targeted educational programs focusing on increasing knowledge and strengthening positive attitudes is essential for promoting preventive practices and mitigating the environmental impacts of microplastics.
Ghazal Yousefian, Seyed Morteza Hodaei, Mohammad Rezvani Ghalhari, Alireza Yousefian, Habib Fasahat, Afshin Ebrahimi,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: The implementation of desalination projects is not without challenges and can have adverse environmental consequences on the environment. The present study was conducted with the aim of assessing the environmental impacts of the desalination of brackish groundwater in the villages of Taft city.
Materials and Methods: Based on field visits to the study area and the prevailing environmental conditions in the region, as well as considering the specific conditions of implementing desalination facilities, questionnaire checklists were used to examine the spatial sensitivity of the project. The Wooten and Rao matrix was used to analyze the relevant environmental activities and consequences.
Results: The results showed that the project overall has a predominance of positive effects, which is confirmed by obtaining a final score of +29. The highest positive scores belong to social and economic dimensions such as income parameters (+27), welfare (+24), and employment (+24). However, the results emphasize the focus of negative impacts on the physical environment, with the most severe impacts being noise pollution (-9) and groundwater resources (-16).
Conclusion: In the present study, the positive impacts outweigh the negative impacts; therefore, implementing this project is deemed appropriate based on the Wooten and Rao matrix criteria, and it does not have any major adverse effects on the region's environment. In addition, the transfer of wastewater to this location has no impact on erosion, compaction, and soil structure degradation, as well as the quality of the aquifers in the region.
Masoumeh Gharaee, Fatemeh Chaparinia, Mostafa Hadei,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: Karbala, as one of the world’s largest religious destinations hosting millions of pilgrims annually, is highly vulnerable to extreme heat events. Understanding temperature dynamics and heat-wave characteristics is essential for anticipating climatic risks and protecting public health during mass gatherings. This study aimed to analyze long-term trends in average, minimum, and maximum temperatures and to assess the frequency, duration, and intensity of heat waves in Karbala from 2009 to 2024.
Materials and Methods: Daily meteorological data—including maximum, minimum, and mean temperatures—were obtained from the GSOD database. Heat-wave events were identified using the Excess Heat Factor (EHF) index, which incorporates both climatic baselines and population acclimatization. Five indicators (HWN, HWF, HWD, HWM, HWA) were calculated to characterize heat-wave behavior. Linear regression was applied to evaluate temporal trends in temperature and heat-wave metrics.
Results: The findings revealed significant increases in annual mean, minimum, and maximum temperatures over the study period. Heat-wave activity intensified, with the number of events and total heat-wave days rising from fewer than 20 days in early years to more than 40 days in several recent years. The longest heat wave extended up to 31 days, and both the intensity and magnitude of heat waves showed an upward trend. These patterns indicate substantial escalation in heat stress conditions consistent with regional warming in the Middle East.
Conclusion: Karbala has experienced clear and concerning increases in temperature and heat-wave severity between 2009 and 2024. The intensification of heat-wave frequency, duration, and intensity underscores growing climatic risks—particularly for pilgrims and vulnerable populations during mass gatherings. Strengthening early warning systems, improving cooling infrastructure, increasing green spaces, and implementing heat-health preparedness measures are essential for enhancing resilience and reducing heat-related health impacts in this climate-sensitive city.
Mojtaba Khatibi, Ghorbanali Dezvareh, Alireza Alizadeh Moghadam Masouleh,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: Due to the lack of the desirable methods of rodent control, the construction of an intelligent rat trap that injects environmentally friendly poison was considered as an effective solution.
Materials and Methods: Based on studies of the length, weight and behavioral characteristics of various types of mice, the initial design of the device was carried out. Using walnut and hazelnut oils, the mouse was guided toward the death tunnel, and the desired chemical was automatically injected into the mouse's chest. The device was first tested with laboratory mice and then with wild samples, and design flaws were examined and resolved at each stage. Data analysis was performed using the chi-square test.
Results: In the death section, two substances—sodium chloride and EDTA—were tested at a concentration of 1 Molar with volumes of 1 mL and 2 mL, respectively, at distances of 2, 4, 6, and 8 centimeters from the rat muzzle. EDTA with a volume of 2 mL achieved a 97% mortality rate (confidence interval 88-99 with a 5% margin of error) at 8 centimeters from the rat muzzle and with an exposure time of 20 seconds. Regarding the comparison between walnut and hazelnut flavors, walnut flavor received the highest attraction score of 93% (confidence interval: 84-98), making it the best parameter in the design.
Conclusion: Due to its ease of use, independence from users’ skill, and environmentally friendly procedure, this method of controlling rat populations is considered an effective, sustainable, and intelligent solution.
Samira Soleimani, Omid Aboubakri,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: Hospital readmission among respiratory patients is an important indicator for evaluating the quality of healthcare services and for assessing the burden of chronic diseases. This study aimed to examine the cumulative effects of PM2.5 and to estimate the attributable risk of respiratory-related readmissions in Sanandaj.
Materials and Methods: In this study, datasets from the Meteorological Organization, hospital readmission records of respiratory patients, along with integrated data from environmental monitoring stations and satellite remote sensing, were utilized. The association between PM2.5 and readmissions was assessed using a semi-parametric regression model with nonlinear functions to control for known and unknown confounders. Based on the model outputs, cumulative effects up to 21 days post-exposure and the attributable risk were estimated, stratified by age and sex.
Results: High concentrations of PM2.5 were significantly associated with cumulative increases in readmissions, particularly among men and individuals under 65 years old. In younger patients (<65 years), there were delayed effects, while in older adults the highest risk occurred during the initial days following exposure. The attributable risk analysis indicated that approximately 3500 readmissions during the study period were attributed to PM2.5 exposure, with the largest proportion observed within the 0–15 μg/m³ concentration range.
Conclusion: This study demonstrated that PM2.5 contributes substantially to respiratory-related hospital readmissions, with effects that were both cumulative and delayed. These findings highlight the need to revise air quality standards, design preventive interventions tailored to age and sex groups, and strengthen early-warning and monitoring systems to reduce the burden of respiratory diseases and healthcare costs.
Bahram Naeimi, Maryam Haddadi, Mahmood Alimohammadi, Mohammad Hadi Dehghani, Mina Aghaei, Fazlollah Changani,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: The rapid expansion of industrial and urban activities in recent decades has led to the increased use of electroplating processes and the generation of wastewater containing heavy metals and toxic compounds such as cyanide and phenol. These pollutants can pose significant risks to human health and the environment. This study aims to conduct a quantitative and qualitative assessment of wastewater from electroplating industries and to evaluate its compliance with discharge standards, thereby providing a basis for improving wastewater management and mitigating environmental impacts.
Materials and Methods: This cross-sectional study was conducted at two nickel–chromium and zinc electroplating units equipped with on-site treatment systems in Tehran Province. Following an assessment of the electroplating processes and treatment units, grab sampling was performed twice on both raw wastewater and effluent samples. In each sampling event, six samples were collected, resulting in a total of 12 samples. Physical and chemical characteristics were measured, and the performance of the treatment systems in removing pollutants was evaluated.
Results: The analytical results indicated that in the effluent from unit 1, the concentrations of COD and nickel, and in the effluent from unit 2, the concentration of zinc, exceeded the established permissible limits. The treatment system in the nickel–chromium electroplating unit exhibited the highest removal efficiency for chromium (100%) as well as for zinc, phosphate, and nickel (94–99%), whereas the removal efficiencies for COD and TSS were estimated at 45% and 69%, respectively. In the zinc electroplating unit, the removal efficiencies for nickel, zinc, COD, and phosphate were approximately 98–99%, while the lowest removal efficiencies were observed for cyanide (50%) and copper (33%).
Conclusion: The findings of this study indicated that the concentrations of several parameters in the treated effluents exceeded the permissible limits established by Department of Environment (DoE) of Iran standards, highlighting the urgent need to upgrade treatment processes and improving wastewater management.
Zahra Fathi Loshkani, Faezeh Mohammadi, Mohammad Mehdi Emamjomeh, Ahad Alizadeh, Azam Janati Esfahani,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: This study investigated the spatial distribution of electric and magnetic field intensities around 63 kV high-voltage power lines located in a public park in Qazvin, Iran. The aim was to evaluate citizens’ exposure to extremely low frequency (ELF) electromagnetic fields through experimental measurement and numerical modeling.
Materials and Methods: This descriptive-analytical research measured electric and magnetic field strengths around 63 kV pylons in four directions and various distances at typical human height (170 cm) across all seasons. Measurements were conducted using a calibrated Holaday field meter during peak power consumption periods. Three-dimensional field propagation was modeled using the COMSOL Multiphysics software and the finite element method (FEM). The obtained data were compared to Iranian national exposure standards and analyzed statistically using R software and the generalized estimating equation (GEE) model.
Results: The intensities of both electric and magnetic fields were highest near the pylons and decreased with increasing distance. The maximum electric field values occurred in spring and summer, while magnetic field maxima appeared in winter. Temperature and humidity exhibited significant effects on the field intensities (p< 0.05). Modeled values were higher than measured ones. Nevertheless, all measured values were below the permissible limits defined by Iranian national standards.
Conclusion: The exposure level of visitors to electromagnetic fields within the studied park was found to be within safe limits and below the national health thresholds. Considering seasonal variations and environmental influences, periodic monitoring throughout the year is recommended. Utilization of natural elements such as vegetation can effectively reduce local field exposure.
Maryam Tahmasebpoor, Hossein Akhtarivand, Fatemeh Mohammadi,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: Carbon dioxide (CO₂), as the main greenhouse gas, plays a critical role in global warming. One of the effective methods for CO₂ capture is the solar-driven calcium looping process. The stable performance and good fluidity of CaO-based sorbents are crucial for the efficiency and durability of this process. This study aims to investigate and enhance the stability and fluidization characteristics of CaO sorbents to improve the performance of solar calcium looping process.
Materials and Methods: To enhance the stability of CaO sorbents, chemical modification with phosphoric and acetic acids was applied. To improve the sorbent's, fluidity, silica particles were added. The performance of modified sorbents was evaluated over 19 cycles for CO₂ capture and regeneration to assess the quantitative and qualitative effects of these treatments on stability and fluidization.
Results: Regarding stability, sorbents modified with acetic acid showed better performance than those modified with phosphoric acid. In contrast, phosphoric acid modification was more effective in improving fluidization behavior. Limestone modified with 10% acetic acid retained a CO₂uptake of 0.3 g CO2/g sorbent after 19 cycles, corresponding to a 57% increase compared to the unmodified limestone. Additionally, at a superficial gas velocity of 5 cm/s, bed expansion of the phosphoric acid-modified sample increased by 27% compared to the raw limestone. By adding 5% silica particles to the acetic acid-modified sample, bed expansion increased by 32%.
Conclusion: Acid modification combined with silica particles addition provides an effective strategy to enhance the performance of CaO sorbents in solar calcium looping processes.
Mohammad Jandkaripour, Mahdi Elyasi Kojabad, Raheleh Haghighi,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: Growing concerns over disinfection by-products (DBPs) resulting from conventional chlorination necessitate the exploration of alternative approaches in water treatment. This study investigates the efficiency of a combined system comprising ozonation and ceramic membrane filtration for drinking water treatment.
Materials and Methods: A ceramic membrane was fabricated using the slip-casting method, characterized, and evaluated for performance. Ozonation efficiency was assessed by injecting 1 g of ozone into a 2.5 L sample (concentration of 0.02 g/L) for 3 minutes. Water quality was monitored by measuring turbidity, total dissolved solids (TDS), major anions and cations, as well as microbiological indicators, including coliform bacteria and Escherichia coli.
Results: Morphological examination confirmed the porous structure of the membrane. The flux test results showed that the membrane flux decreased from 475 Lmh to 313 Lmh, with 96% recovery through backwashing. The membrane reduced turbidity from 1.72 NTU to 0.5 NTU, representing a 71% removal efficiency compared to the pre-filtration sample. Ozonation had no effect on water turbidity but achieved complete removal of coliform bacteria and Escherichia coli. In contrast, membrane filtration achieved 66% removal of these bacteria.
Conclusion: Membrane filtration removes the majority of contaminants when employed as a complementary method to either ozonation or chlorination, allowing for the subsequent use of a mild disinfectant to eliminate remaining trace microbial content. The combined application of low-concentration ozonation and chlorination prevents the formation of DBPs, representing a step toward providing safer and healthier drinking water.
Hamideh Akbari, Aida Jasour, Hassan Rasoulzadeh, Ali Zafarzadeh, Rozhan Feizi,
Volume 19, Issue 1 (6-2026)
Abstract
Background and Objective: Since the presence of heavy metals in milk and dairy products is a health concern, this study aimed to evaluate the concentrations of lead, cadmium, copper and zinc in raw milk and traditional dairy products, and to conduct a related risk assessment.
Materials and Methods: 30 samples of milk and dairy products including yoghurt, cheese, and doogh were collected from ten traditional dairy production store in Khuzestan province. The samples were digested in the laboratory using nitric acid method digestion, and the heavy metal concentration was measured using Metrohm 797. Hazard Quotient (HQ) and Hazard Index (HI) were calculated for non-carcinogenic risk and Estimated Daily Intake (EDI) was calculated for carcinogenic risk assessment using Monte Carlo simulation.
Results: The mean concentration of lead, cadmium, zinc and copper in the dairy were 0668, 0069, 0952 and 8756 mg/kg, respectively. The total heavy metal concentrations in yoghurt, doogh and cheese were 134.08, 24.19 and 4.17 percent higher than in raw milk, respectively. The HI from dairy product consumption was 52.82E-2. The EDI for lead and cadmium in dairy products were in the range of 10-4 and10-8, respectively.
Conclusion: Although common attitude toward better quality of traditional dairy products, the traditional process increases the concentration of some heavy metals in comparison with in raw milk. Monitoring of heavy metals in traditional dairy products and defining a control strategy is recommended.
