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Contamination and source apportionment of iron, zinc, cadmium and chromium elements in surface soil of Khorramabad county, Iran
Masoumeh Selahvarzi, Soheil Sobhanardakani, Amir Hooman Hemmasi, Lobat Taghavi, Jamal Ghoddousi,
Volume 15, Issue 4 (3-2023)
Abstract
Background and Objective: Soil contamination with heavy metals is the most important challenge and common environmental, economic, and public health issue in the world. Therefore, this research was conducted to evaluate the contamination and source identification of Fe, Zn, Cd, and Cr in the surface soils of Khorramabad county, west of Iran in 2020.
Materials and Methods: In this descriptive study, after dividing the study area into 11 homogeneous units, a total of 65 surface soil samples were collected. After preparing the samples, the content of the elements was determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, enrichment factor (EF), pollution factor (CF), and Nemrow integrated pollution index (NIPI) were calculated. Statistical analyses of the data were performed using SPSS statistical software.
Results: The results showed that the average content of Fe, Zn, Cd, and Cr (mg/kg) in soil samples were 3.14, 1.13, 0.021, and 0.529, respectively. The EF values showed that the enrichment of Zn, Cd, and Cr was "extremely severe" and the average values of EF for the elements followed the descending order of Cd > Cr > Zn. The average values of CF and NIPI varied from 3.30×10-5 to 0.182 and 0.043-0.136, respectively, indicating the level of "low pollution" and quality conditions of "no pollution" in all the studied stations. Based on the results of multivariate statistical analysis (PCC, PCA and HCA), Fe has a geological origin; while, Zn, Cd, and Cr mainly originated from a combination of geological processes and anthropogenic activities.
Conclusion: Although the average values of CF and NIPI showed that the study area has an acceptable soil quality, the values of EF indicated the impact of anthropogenic activities on soil contamination. Therefore, regular and periodic monitoring of soil samples as well as management and control of pollutant emission sources is recommended for maintaining environmental and human health.

Comparing the efficiency of vacuum ultraviolet and ultraviolet-C for the degradation of Remdesivir in the contaminated water
Mahboobeh Motalebi, Gholamreza Moussavi, Sakine Shekoohiyan,
Volume 16, Issue 1 (6-2023)
Abstract
Background and Objective: Vacuum Ultraviolet (VUV)-based advanced oxidation is a new category of advanced purification processes, so this study aimed to compare the efficiency of VUV and Ultraviolet-C (UVC) processes in combination with H2O2 and PMS in degrading Remdesivir.
Materials and Methods: The photoreactor was investigated with VUV and UVC lamps in combination with H2O2 and PMS for Remdesivir degradation. Also, the effect of variables such as solution pH, H2O2 dose, Remdesivir concentration, the presence of radical scavengers and anions, as well as hydraulic retention time was considered in the continuous process of Remdesivir removal.
Results: The findings showed that the optimal pH in the processes of VUV, UVC, and their derivatives was equal to 7. By adding 1 mM of PMS and H2O2 to the VUV process, the degradation efficiency of Remdesivir was increased from 92.2 ± 0.4% to 98.3 ±2.1% and 100 ± 0.3%, respectively, after 30 min. Also, in the UVC process combined with H2O2 and PMS, the degradation efficiency reached 77.8 ± 1.5 and 85.2 ± 1.3% after 40 min, respectively. The degradation kinetics in the examined processes were as follows: VUV/H2O2 > VUV/PMS > VUV > UVC/H2O2 > UVC/PMS > UVC. The hydroxyl radical was the main reactive oxygen species that led to the decomposition of Remdesivir. The continuous operation of VUV/H2O2 showed that the removal efficiency of Remdesivir reached 94.7 ±0.8% after 40 min.
Conclusion: Considering the high rate of Remdesivir degradation by adding H2O2, the VUV/H2O2 process can be introduced as an efficient technology for the removal of antiviral drugs.
 

Environmental health management during the Muharram and Safar mourning ceremonies based on the analytic hierarchy process
Ahmad Jonidi Jafari, Davarkhah Rabbani, Samaneh Bagheri Arani, Ehsan Zarei, Mohsen Hosami Arani,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: Compliance with the principles of environmental health is of particular importance in any gathering ceremony. This issue needs more attention in the Muharram and Safar mourning ceremonies due to the position of health in Islam and the presence of different populations in this ceremony. Based on this, the present study was conducted with the aim of environmental health management during Muharram and Safar days using the Analytic Hierarchy Process.
Materials and Methods: According to the main purpose of the study, a literature review was done. Then, a team of experts was formed and criteria, sub-criteria and programs related to the purpose of the study were determined by brainstorming, and the relevant questionnaire was prepared and after completion by 25 experts, the relevant criteria were prioritized using the Analytic Hierarchy Process.
Results: Based on the weighting with the Analytic Hierarchy Process method, the highest score (0.441) was awarded to the health inspection criteria, and then the administrative coordination criteria(0.186), education (0.182), reporting (0.169) and finally the support and services criterion (0.022) were prioritized.
Conclusion: The results of the study indicate the emphasis on environmental health management during the Muharram and Safar mourning ceremonies from the point of view of experts, that compliance with the three principles of health inspection, administrative coordination and continuous training has the particular importance.
 

Identification of the landfill site of Bushehr city by using the combined method of DEMATEL and Network Analysis Process (DANP)
Saeed Karimi, Bahareh Rahimipour,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Waste management is a crucial aspect of sustainable city development due to the increasing population, urbanization expansion, and changes in consumption patterns. The purpose of this study is to identify the waste landfill in Bushehr city by considering the relationships between various criteria using the DANP (DEMATEL-ANP) method.
Materials and Methods: 17 criteria were identified to identify the suitable landfill. The weighting of these criteria was done by DANP integrated multi-criteria decision-making technique. The internal relationships of the criteria and the causal relationships between the criteria were also determined. Then, these weights were multiplied in the spatial layer of each of the criteria in the environment of geographic information systems.
Results: The most crucial criterion for selecting a suitable location for urban landfill is land use, followed by the criteria of distance from residential areas, tourist places, and the road. The study identified and evaluated five locations in Bushehr city as potential landfills based on these criteria. The eastern and southeastern parts of Bushehr city emerged as the most suitable locations for landfill among the evaluated sites.
Conclusion: The DANP model proves highly effective in identifying landfills and offers a framework for addressing issues related to waste landfill selection. This research can serve as a valuable guide for planning and locating waste landfills, providing a basis for addressing both theoretical and practical challenges associated with landfill management.
 

Investigating environmental pollutants released in integrated urban waste management centers (case study: Koohak)
Sadaf Moeini, Seyed Masoud Monavari, Fariba Zamani Hargolani,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: The increase in waste at integrated urban waste centers, along with the problems and adverse environmental consequences due to their inappropriate establishment have become more apparent. This research was conducted with the aim of determining and investigating environmental pollution in urban waste integration management centers.
Materials and Methods: This research investigated the environmental pollutants in the integrated waste center in Koohak at various distances ranging from 0 to 900 meters. Four main criteria—waste, water pollution, air pollution and sound pollution—were determined, each with 16 sub-criteria. The map of each criterion and sub-criteria were multiplied by the coefficients they received from the weights obtained using the Analytical Network Process (ANP) method. By combining the criteria using the Weighted Linear Combination (WLC) method and superimposing them, finally, the studied area was ultimately classified into three classes: inappropriate, medium, and suitable.
Results: Air pollution, with a weight of 0.26, had the highest rating compared to the other three criteria. Noise pollution (0.25), water pollution (0.24) and waste-related criteria (0.23) were ranked next. The results of the Kruskal-Wallis test indicated a significant difference in pollutant concentrations between different stations (p<0.05). Additionally, the results show that the average concentration of pollutants at distances of 0-300 meters differed significantly from those at all other distances (p<0.05). After determining the suitable zones using the WLC method, the results showed that 62.5 percent of the criteria were approved by the environmental organization.
Conclusion: By examining the results of the methods used in this research, it can be concluded that the combination of ANP and WLC methods provide effectivee results. However, uncertainty in subjective decisions and time constraints in decision-making have posed challenges in assessing waste collection in integrated urban waste centers.
 

Modification of anaerobic composting process using natural clinoptilolite zeolite on the quality of physical and chemical properties
Fariba Asghari, Ayoob Rastegar, Mohammad Hossien Saghi,
Volume 17, Issue 4 (3-2025)
Abstract
Background and Objective: Composting is a sustainable solution for recycling organic solid waste (OSW). Various compounds can be used to enhance the quality of compost. This study aimed to investigate the effects of zeolite on the physical and chemical characteristics of compost produced through the anaerobic process.
Materials and Methods: This analytical study was conducted in 1402 at Kimia Sabzevar Company, located 5 km from Rudab Road. Cow manure and natural clinoptilolite zeolite were used in varying proportions (0%, 5%, 10%, 15%, and 20% of the total reactor volume) to prepare fertilizer via the anaerobic method. After 30, 45, and 60 days, a total of 90 samples were collected and sent to the laboratory for analysis. Parameters such as pH, electrical conductivity, temperature, carbon-to-nitrogen ratio, and nitrate content were measured to evaluate the quality of the fertilizer product.
Results: The results showed that in the early stages, pH changes were less pronounced in treatments with varying zeolite percentages, ranging from 7.9 to 8.57. The addition of zeolite in the composting process influenced temperature dynamics, with higher zeolite percentages maintaining elevated temperatures. Moreover, the nitrate content increased by 15% during the process.
Conclusion: The findings indicate that adding zeolite to fertilizer enhances temperature stability, accelerates the composting process, and reduces the time required for fertilization. Additionally, zeolite improved the physicochemical properties of the fertilizer produced through the anaerobic process.
 

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