Environmental Health Engineering and Management Journal

137-146

Authors: Reman Mohammed Mahgoob Al-Azzawi, Atefeh Chamani

Background: Cities negatively affect the environment. Urban pollution levels have risen considerably, affecting sensitive groups such as pregnant women. Methods: This study aimed to investigate the relationship between particulate matter and kidney biomarkers of pregnant women in Yazd from September to November 2023. Urea, uric acid, and creatinine levels were measured in 30 pregnant women (third trimester). The concentration of PM2.5 was estimated using the land use regression (LUR) model and 5 independent variables of road networks, distance from the city center, building density, elevation, and slope. For each mother, the mean concentration of the modeled PM2.5 was measured in multiple buffer rings drawn around her residential location. Generalized additive model (GAM) was employed to establish a relationship between PM2.5 concentrations with physiological indicators. Results: Average urea, uric acid, and creatinine were 18.06 ± 5.74, 3.65 ± 1.11, and 0.79 ± 0.12 mg/dL, respectively. The LUR model identified road networks and distance from the city center as critical factors contributing to increased particulate matter concentration. The GAM R2 was 0.79, 0.31, and 0.28 for urea, uric acid, and creatinine, respectively. The mean PM2.5 within a radius of 2000 m was identified as the most significant independent variable and showed an increasing impact on the renal parameters. Conclusion: According to the results, reducing pollutant levels and preventing the creation of pollution hotspots via lowering road density are vital urban planning strategies to protect vulnerable groups, especially pregnant women.

161-166

Authors: Kamyar Yaghmaeian, Masoud Panahi Fard, Mehdi Ahmadi Moghadam, Maryam Mousavi, Neematollah Jaafarzadeh, Maryam Omidinasab, Bamshad Shenavar, Rozhan Feizi

Background: Wastewater treatment plants are important sources of emissions of greenhouse gases (GHSs) such as carbon dioxide and methane in the atmosphere. Also, energy consumption in the wastewater treatment process causes indirect carbon dioxide emissions. Methods: One hundred thirty-three operating wastewater treatment plants in Iran treat municipal wastewater. The carbon dioxide and methane emissions from the wastewater treatment plants for the year 2022 were estimated by establishing a calculation model according to the methods recommended by the Intergovernmental Panel on Climate Change for National Greenhouse Gas Inventories (2006) and United States Environmental Protection Agency (USEPA) guidelines. Results: Based on the Intergovernmental Panel on Climate Change guideline, the total methane emission was 158.63 tons. Based on the USEPA guideline, the total emissions of methane and carbon dioxide were 47.61 and 351.47 tons, respectively. This amount is 3.2% of all the methane and carbon dioxide emissions of Iran. Isfahan and Tehran provinces have the highest emissions rates of methane at 31.85 and 22.91 tons, respectively. While South Khorasan and Kerman provinces have the lowest methane emissions rates of 0.46 and 0.67 tons, respectively. Conclusion: The results will provide a scientific basis and effective strategies for policymakers to reduce the methane and carbon dioxide emissions from the wastewater treatment plants of Iran.

177-190

Authors: Mohammad Ali Zazouli, Zabihollah Yousefi, Esmaeil Babanezhad, Reza Ali Mohammadpour, Alireza Ala

Background: Modifying and enhancing treatment methods is essential to meet effluent standards for treating landfill leachate. This study investigated the treatment of municipal solid waste leachate (MSWL) using coagulation, flocculation, advanced oxidation, and extended aeration processes. Methods: The effects of different coagulant doses and pH values on coagulation processes were compared. The treatment procedure was analyzed to determine the impact of varying concentrations of potassium persulfate (K2S2O8) and hydrogen peroxide (H2O2) on the results after coagulation with FeCl3. The extended aeration process’s biological stages were studied using a sludge retention time (SRT) of 23 days and the effects of hydraulic retention time (HRT) of 18 and 36 hours. Results: The experimental results show that in the pH range of 5–8, the lower the pH value, the higher the treatment efficiency. The addition of 0.8 g L1− FeCl3 can achieve a 57% removal of chemical oxygen demand (COD). The addition of 2.5 g L1− K2S2O8 and 1.5 g L1− H2O2 with UV-C (15 W) for 70 minutes at pH 7 can effectively remove 86% of COD. Activated sludge extended aeration can attain an 88% removal of COD under optimal operating conditions (HRT = 36 hours, SRT = 23 days, and aeration = 36 hours). The studied hybrid process with the efficiency of 99%, 98%, 95%, 87%, and 83% removal of COD, biochemical oxygen demand (BOD), total suspended solids (TSS), turbidity, and total Kjeldahl nitrogen (TKN), respectively, is suitable for leachate treatment. Conclusion: This study showed that flocculation-coagulation followed by the advanced oxidation process (AOP) and extended aeration can be an efficient and promising treatment method for MSWL.

201-209

Authors: Herdianti, Dewi Susanna, Tris Eriando, Hasmah Abdullah, Risky Cyndythia

Background: Uninhabited shophouses become breeding places for mosquitoes which cause high levels of dengue hemorrhagic fever (DHF), whereas the existence of squatters causes a reduction in green open space, one of which becomes a breeding place for Aedes sp. Methods: This study aimed to develop a DHF risk model in shophouses and squatters in Batam city. This research applied an ecological study design using a spatial approach with the geographically weighted regression (GWR) method. The variables studied were the incidence of dengue fever, vector density, and rainfall. Results: The results of the analysis show that for the vector density in the shophouses, the odds ratio (OR) was 4.71 while for the vector density in squatters, the OR was 6.76. For the rainfall in the shophouses, the OR was 0.83 while for the rainfall in the Squatters, the OR was 1.68. Model analysis shows that the higher shophouses and squatters can cause an increase in dengue cases. Conclusion: Risk analysis shows that factors that can increase DHF vulnerability include high vector density with a risk of 4.71 times (shophouses) and 6.76 times (squatters), and high rainfall in squatters with a risk of 1680 times. The distribution of dengue cases shows that Sambau dan Batu Selicin are subdistricts that have a high distribution of vulnerabilities in both shophouses and squatters. The mathematical model of dengue risk shows that every construction of one shophouse or one squatter can cause an increase in dengue cases by one case.

219-228

Authors: Simin Khojasteh Noshari, Javid Imanpour Namin, Mohammad Forouhar Vajargah, Mehdi Bibak

Background: Wetlands are among the most important ecosystems and areas of life that are ecologically and economically important in the world and susceptible for heavy metal contamination. The elements in water and sediment may be easily and in large quantities available to animals in aquatic ecosystems. This study aimed to investigate the level of heavy metal contamination in Anodonta cygnea. Methods: Anodonta cygnea sampling was carried out in the summer 2023. A total of 35 specimens were collected randomly by fishing net. Following the laboratory analyses, the concentration of aluminum (Al), arsenic (As), copper (Cu), cobalt (Co), cadmium (Cd), iron (Fe), manganese (Mn), magnesium (mg), lead (Pb), nickel (Ni), tin, vanadium (V) and zinc (Zn) were determined by ICP-OES. Results: Target hazard quotient (THQ) values of Mn were above 1. The pi index showed that A. cygnea is slightly contaminated by Pb. Analyses of the metal accumulation showed that A. cygnea bivalve was moderately contaminated by Zn and severely contaminated by As. The results showed no significant relationship between the total weight of the organism and concentration of Al, Fe, and Ni. Conclusion: Aquatic organisms, including bivalves, do not possess an advanced excretory system, therefore the excretion of metabolites and pollutants is a is a slow process. once the concentration of heavy metals in the aquatic environment increases, they become easily available to aquatic organisms and enter the biological system. In this study, the absorption rate of metals was higher than its excretion or removal by the excretory system which results in their accumulation in various tissues and organs of the organism.

237-256

Authors: Sara Karimi Zeverdegani, Farzaneh Mohammadi, Adel Mohammadalipour, Mohammad Hashemnia, Zohreh Mohebian

Background: Welding fumes (WFs) contain heavy metals that can induce oxidative stress and health issues in welders. This review investigated the relationship between oxidative stress biomarkers and trace metals in welders’ bodily fluids. Methods: Online databases such as Scopus, PubMed, Web of Science, Science Direct, EMBASE, and Google Scholar were reviewed, with a specific emphasis on the effects of metal fume exposure during welding. Specific keywords such as “welding fumes”, “metal fumes”, “antioxidant enzymes”, “biomarkers”, and similar terms were employed to search for articles published between 2004 and 2023. After the evaluation of article titles and abstracts, this study reviewed a total of 19 articles. Results: Studies suggest that welders experience oxidative stress due to changes in trace metals in their body fluids, affecting antioxidant enzymes and oxidative stress biomarkers. Elevated heavy metals in welders’ biological samples lead to oxidative stress and inflammation, even at low levels. Certain metals in blood and urine, such as lead (Pb), manganese (Mn), iron (Fe), chromium (Cr), and cadmium (Cd), positively correlate with serum superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels. There is also a significant positive correlation between serum/EBC MDA and blood/urine Pb, Mn, Cd, Cr, and Fe, indicating cellular damage, lipid peroxidation, and reduced antioxidant capacity. Additionally, welders may experience more DNA damage compared to non-welders. Conclusion: Exposure to WFs significantly altered oxidative stress biomarkers in bodily fluids, underscoring the importance of the relationship between oxidative stress and trace metal imbalances in WF-related injuries. These factors could serve as valuable biomarkers for monitoring workers exposed to WFs.