Journal of Environmental Health and Sustainable Development

The Critical Role of Quantitative Structure Activity Relationship in Predicting the Removal of Organic Micropollutants

Sahar Garzegar — 2025-12-30

The Article Abstract is not available.

Systematic Review of Occupational and Environmental Exposure to Anesthetic Gases in Operating Rooms: Pregnancy Outcomes in Iranian Healthcare Professionals

Mahrokh Jalili — 2025-12-30

Introduction: Operating room personnel are exposed to various occupational hazards that may pose health risks. Advances in anesthetic techniques and ventilation have reduced waste anesthetic gas exposure; however, concerns regarding potential reproductive risks persist. This review aims to summarize the current evidence on occupational exposure to anesthetic gases in operating rooms, focusing on their impact on pregnancy outcomes among healthcare professionals in Iran.

Materials and Methods: A systematic review was conducted on studies published between January 2000 and May 2025, identified through international and Iranian scientific databases, including the Web of Science, PubMed, Scopus, ScienceDirect, SID, Magiran, and IranDoc. Relevant studies were retrieved using keywords such as “Environmental exposure,” “Occupational exposure,” “Anesthetics,” “Operating room,” and “Pregnancy outcome” in both Persian and English languages. Finally, five articles were selected for the final analysis.

Results: The reviewed evidence showed mixed results regarding spontaneous abortion and preterm birth rates. Some studies have found a significant association between anesthetic gas exposure and these outcomes, while others have not reported any such association. Two studies have reported a significant association between anesthetic gas exposure and infertility. No significant relationship between anesthetic gas exposure and low birth weight was observed in the studies reviewed.

Conclusion: These findings suggest a potential association between occupational exposure to anesthetic gases and adverse pregnancy outcomes. Given the limited and methodologically limited studies in Iran, further well-designed prospective research and improved workplace safety measures are needed to clarify these associations and minimize the potential risks for operating room personnel.

Dental Amalgam-Derived Mercury in Wastewater: A Systematic Review of Environmental and Health Impacts, and Control Strategies

Mahla Mazloomian — 2025-12-30

Introduction: Dental amalgam, a mercury-based restorative material, is a significant point source of environmental mercury contamination in clinical wastewater. Mercury and other heavy metals from dental clinics enter wastewater systems untreated, posing risks to ecosystems and human health. This review uniquely bridges the critical gap between dental practice effluent pathways, quantitative environmental risk assessment, and practical evaluation of mitigation technologies.

Methods: A comprehensive literature search was conducted using Scopus, Web of Science, PubMed/MEDLINE, and Embase for publications from 2000 to 2024. This review focused on studies quantifying mercury in dental wastewater and evaluated the effectiveness of containment, treatment, and policy measures.

Results: The findings confirmed that dental clinics contribute substantially to mercury loads in wastewater, with a single chair releasing as much as 4.5 g/day. Reported mercury concentrations in dental effluent vary widely, ranging from 0.90 µg/L to 39 mg/L, reflecting differences in clinical practices and control measures. The primary mitigation technology is amalgam separators, which can remove more than 90% of amalgam particles and are increasingly required by regulations, such as the U.S. Environmental Protection Agency 2017. A multi-faceted approach combining separators, optimized chairside practices, waste segregation, and staff education is essential for effective management.

Conclusion: Despite the declining use of dental amalgam, it remains an important environmental concern. Effective mitigation requires a combination of stringent policies, proven technologies, and professional stewardship. Future efforts should prioritize standardized monitoring, long-term performance data on control measures, and robust cost-benefit analyses to guide sustainable dental practices.

Electrocatalytic Oxidation for Removal of COD from Chlorpyrifos Contaminated Wastewater: Optimization and Performance

Maryam Dolatabadi — 2025-12-30

Introduction: The removal of chemical oxygen demand (COD) associated with the pesticide chlorpyrifos (CPS) is critical for protecting aquatic ecosystems and public health. Additionally, incomplete degradation of CPS can yield recalcitrant or more toxic transformation products, thereby increasing ecological and human health risks. Therefore, it is essential to removal the COD contributions attributable to CPS from polluted water.

Materials and Methods: In this study, response surface methodology (RSM) was applied as an effective approach to optimize COD removal during anodic oxidation (AO). The effects of the operational parameters, namely CPS concentration, current density, and reaction time, were assessed and subsequently optimized.

Results: The model’s predicted COD removal closely matched experimental observations, exhibiting an R² of 0.9915. ANOVA confirmed the significance of the fitted quadratic model, a high F valuee (324.7), and regression coefficients approaching unity at the 95% confidence level. The lack-of-fit p-value (0.6071) indicates that the lack of fit is not significant. Under optimized conditions, with an CPS concentration of 17.0 mg L⁻¹, current density of 35 mA cm⁻², and a reaction time of 75 min, the maximum COD removal eeficiency reached 70.2%, with an electrical energy consumption of 0.218 kWh m^-3.

Conclusion: ^•OH was the predominant oxidizing species mediating the removal of COD associated with CPS during the AO process. The AO process, recognized for its environmental compatibility, was successfully applied for COD removal. The AO process is an effective treatment for pesticide-contaminated wastewater.

Ultrasonic-Assisted Degradation of Metformin from Pharmaceutical Effluent: Process Optimization via Response Surface Methodology

Shital P. Dehankar — 2025-12-30

Introduction: Metformin, an extremely prescribed antidiabetic medication, is discharged with minimal or no processing and remains during the usual wastewater treatment procedures. Advanced oxidation processes (AOP), especially ultrasound-enabled oxidation, are catalyst- and sludge-free reaction pathways for degrading recalcitrant pharmaceuticals. This study aimed to (i) determine the ultrasound-assisted degradation of metformin using hydrogen peroxide, (ii) determine the effect of the main operation parameters, and (iii) optimize the chemical oxygen demand (COD) and total organic carbon (TOC) using Response Surface Methodology (RSM).

Materials and Methods: Five process parameters were optimized: pH (3-9), ultrasonic power (60-150 W), sonication time (10-60 min), H₂O₂ concentration (0-1.0 mL/L), and initial metformin concentration (5-50 mg/L). Dual response variables, including COD and TOC removal, were analyzed via quadratic polynomial regression. Metformin concentration was quantified using high-performance liquid chromatography at a detection wavelength of 240 nm.

Results: Optimal operating conditions were identified as pH 3.5, ultrasonic power 110 W, sonication time 40 min, and H₂O₂ concentration 0.65 mL/L, achieving 94.5% COD removal, 88.3% TOC removal, and 97.2% metformin degradation. Both statistical models demonstrated high significance (p < 0.0001) with a coefficient of determination R² > 0.96 and a composite desirability of 0.9845 (98.45%), confirming excellent multi-response optimization.

Conclusion: Metformin significantly reduced the organic load, and the drug was significantly degraded by ultrasonic-assisted oxidation. The optimization method based on RSM offers predictive models that can be used to design the process or the performers.

Comparative Efficiency of Mesophilic Anaerobic Digestion and Aerated Static Pile Composting in the Stabilization of Municipal Wastewater Sludge

Mohammad Hasan Kowsari — 2025-12-30

Introduction: Stabilization of municipal wastewater sludge is a critical requirement for mitigating environmental and public health risks. This study provides a comparative evaluation of mesophilic anaerobic digestion (AD) and aerated static pile (ASP) composting for sludge stabilization at Iran’s largest municipal wastewater treatment plant, with a focus on process efficiency, hygienic quality, and end-product usability.

Materials and Methods: Laboratory-scale experiments were conducted using batch mesophilic anaerobic digestion (35 °C, 24 days) and aerated static pile composting. The composting process employed sludge conditioned with bulking and amendment agents under controlled aeration, including a 6-day thermophilic phase within a 30-day operational period. Process performance was assessed based on volatile solids reduction, pathogen inactivation, and biogas production.

Results: ASP composting demonstrated superior stabilization and hygienization performance, achieving more than 50% volatile solids reduction and over 3-log fecal coliform reduction, resulting in compost meeting USEPA Class A standards. In contrast, anaerobic digestion achieved approximately 40% volatile solids reduction and produced 5405 mL of biogas, yielding biosolids classified as USEPA Class B.

Conclusion: While mesophilic anaerobic digestion offers the advantage of renewable energy recovery, aerated static pile composting provides a more hygienically robust pathway for producing stabilized, high-quality compost suitable for agricultural applications. The findings highlight that the selection of sludge treatment technology should be context-driven, balancing priorities between energy generation and the production of sanitized, agriculturally valuable biosolids.

The Effect of Subacute Exposure to Low-Density Polyethylene (LDPE) Microplastics on Oxidative Stress and Membrane Damage in Alveolar Macrophage Cells of Rattus Norvegicus Wistar Strain

Tri Marthy Mulyasari — 2025-12-30

Introduction: Inhalation of microplastics (MPs) can damage lung tissue. Alveolar macrophages express superoxide dismutase (SOD) as a defensive response to foreign substances. Additionally, F2-isoprostane (IsoP) is a specific biomarker of oxidative stress induced by reactive oxygen species (ROS). This study aimed to analyze the effects of Mps inhalation on alveolar macrophages.

Materials and Methods: This true experimental study employed a post-test-only control group design using 21 Wistar rats. MPs aerosols at concentrations of 1 mg/L/day and 2 mg/L/day were inhaled for 28 days. Airborne MPs were measured using passive sampling methods. SOD and IsoP expression levels were evaluated using immunohistochemistry, and their correlations with MPs levels were analyzed using Spearman’s rank correlation test.

Results: The average level of MPs in the air chamber of treatment group 1 was 17.59 particles/unit chamber, and that of treatment group 2 was 35.95 particles/unit chamber. The average expression of SOD and IsoP in the 1 mg/L exposure samples was 15.16 cells/field of view and 17.54 cells/field of view, while in the 2 mg/L exposure samples, there were 10.63 cells/field of view and 23.28 cells/field of view. The effect of MPs levels in chamber air on the expression of SOD and IsoP in alveolar macrophages in lung tissue was significant (p < 0.05).

Conclusions: Subacute exposure to MPs causes oxidative stress and damage to the membrane of macrophage cells. The dose of exposure to MPs in the study may be higher than the presence of MPs in the air in reality.

Health Risk Assessment of Exposure to SO2 and NO2 Resulting from Power Plant Fuel Change Using Monte Carlo Simulation

Amir Sheikhmohammadi — 2025-12-30

Introduction: Exposure to air pollutants is a serious concern that leads to numerous health issues. Power plants are one of the main sources of pollutant emissions, including sulfur dioxide and nitrogen dioxide. This study aimed to estimate the non-carcinogenic risk associated with exposure to SO₂ and NO₂ at a power plant in northwestern Iran.

Materials and Methods: SO₂ and NO₂ concentrations in the power plant exhaust gas and the power plant area were collected from official data recorded during regular monitoring. The health risk of exposure to the detected concentrations of SO₂ and NO₂ was assessed by calculating the hazard quotient based on the estimated chronic daily intake.

Results: The analysis showed that the concentrations of SO₂ and NO₂ in the studied area were 12.60 and 20.18 μg/m³, respectively. However, the concentrations of the total studied pollutants in winter were 45.10% higher than those in summer. In addition, the mean hazard quotient of exposure to SO₂ and NO₂ was calculated as 0.0369 and 0.0905, respectively. But, the use of diesel for energy production in a power plant resulted in a 65.07% higher non-carcinogenic risk than the use of gas as a power plant fuel.

Conclusion: Although the health risk of exposure to the studied pollutants was not significant (HI = 0.127) in the current situation, the use of diesel significantly increased the health risk owing to increased pollutant emissions.