https://www.ehpr.ir/ Environmental Health and Pollution Research en daily 1 Thu, 01 Jan 2026 00:00:00 +0330 Thu, 01 Jan 2026 00:00:00 +0330 https://www.ehpr.ir/article_233487.html Effective hospital waste management is vital for public health and environmental sustainability in growing urban centers like Isfahan, Iran. This study analyzed waste generation, composition, treatment, and disposal barriers across four hospitals (representing ~20% of Isfahan's hospital waste) to identify practical solutions. Using a mixed-methods approach from January to June 2025, quantitative waste audits and qualitative interviews with 20 stakeholders were conducted. Findings revealed an average daily waste generation of 3,232 kg, with 29% infectious waste—exceeding WHO guidelines (15–20%) due to poor segregation. Public hospitals relied heavily on incineration (55–60%), yet only 50% of incinerators had gas-cleaning systems. Private hospitals preferred autoclaving (50–55%) and showed higher compliance with standards (80–85% vs. 65–70%). Key barriers included inadequate segregation (80% of respondents), insufficient infrastructure (65%), and funding shortages (60%). The COVID-19 pandemic exacerbated challenges, increasing landfilling rates 3.6-fold due to PPE waste surges. Recommendations include enhanced staff training, investment in advanced technologies like plasma pyrolysis, and stricter regulatory enforcement. Adopting circular economy principles, such as composting, could reduce landfill reliance, offering a roadmap for Isfahan and similar urban settings. https://www.ehpr.ir/article_235896.html Urban air pollution poses significant health risks, particularly for individuals with prolonged exposure to traffic-related emissions. This study aimed to assess the concentration and distribution of PM10 and PM2.5 particulate matter among taxi and bus drivers in Rasht, Iran, and to identify key environmental and occupational predictors of exposure. A cross-sectional observational design was employed, involving 120 drivers (60 taxi, 60 bus) selected through stratified random sampling across high-traffic urban zones. Real-time measurements of PM10 and PM2.5 were collected using portable air quality monitors installed in vehicle cabins, supplemented by GPS tracking and meteorological data. Descriptive statistics revealed that bus drivers experienced higher mean concentrations of PM10 (97.8 µg/m³) and PM2.5 (74.3 µg/m³) compared to taxi drivers (PM10: 84.2 µg/m³; PM2.5: 62.5 µg/m³). One-way ANOVA indicated significant differences in exposure across urban zones, with central districts showing the highest particulate levels (p < 0.01). Multivariate regression analysis identified traffic density as the strongest positive predictor of PM exposure, while effective cabin ventilation and favorable meteorological conditions were associated with reduced concentrations. These findings underscore the occupational vulnerability of urban transport workers and highlight the need for targeted interventions. Recommendations include retrofitting vehicles with high-efficiency filtration systems, optimizing traffic flow, and implementing exposure monitoring programs in high-risk zones. The study contributes to the growing body of evidence supporting localized air quality management and occupational health protections in urban environments. https://www.ehpr.ir/article_235898.html Access to safe drinking water is critical for public health, yet rural areas often face contamination challenges. This study aimed to assess the physical and microbial quality of drinking water in 10 villages of Sanandaj city, Iran, to identify contamination risks and inform water management strategies. A stratified random sampling approach was used to collect 400 water samples (100 per quarterly round) from source, storage, and distribution points across wells, springs, and piped systems over 12 months. Samples were analyzed for pH, turbidity, residual chlorine, total coliforms, fecal coliforms, and heterotrophic plate counts (HPC) following standard protocols (APHA, 2017). Results revealed pH values within WHO guidelines (6.5–8.5), but 12% of distribution point samples exceeded the turbidity threshold of 5 NTU, and residual chlorine levels were consistently low (0.12–0.22 mg/L). Microbial contamination was widespread, with total coliforms detected in 82% of samples and fecal coliforms in 55%, particularly at distribution points (16.2 and 4.8 MPN/100 mL, respectively). HPC remained below 500 CFU/mL but increased from source to distribution, suggesting biofilm formation. Summer months showed higher turbidity and fecal coliforms due to runoff and temperature effects. The Water Quality Index classified six villages as “poor” (WQI < 70) and four as “fair” (WQI 70–80), with spring-based systems performing better. These findings highlight inadequate disinfection, aging infrastructure, and environmental vulnerabilities as key contamination drivers. Urgent interventions, including enhanced chlorination, source protection, and pipe maintenance, are needed to ensure safe drinking water and reduce health risks in rural Sanandaj. https://www.ehpr.ir/article_233488.html This study aimed to quantify N-nitrosamine concentrations in fast foods sold in Tehran, Iran, and to identify the key factors influencing their formation, in order to inform safer food production practices and reduce dietary exposure risks. A cross-sectional analysis was conducted on 120 fast food samples (burgers, sausages, and kebabs) collected from 40 outlets (20 international chains, 20 local vendors) between March and June 2025. Seven volatile N-nitrosamines were analyzed using gas chromatography–mass spectrometry (GC-MS). Data on cooking methods, meat percentage, sodium nitrite use, and storage conditions were obtained through structured questionnaires. Statistical analyses, including ANOVA and multiple linear regression, were performed to identify significant predictors. Sausages exhibited the highest total nitrosamine levels (10.78 ± 3.60 µg/kg), followed by burgers (7.88 ± 2.58 µg/kg) and kebabs (6.30 ± 2.15 µg/kg). Local vendors showed higher levels (9.45 ± 3.15 µg/kg) than international chains (7.25 ± 2.30 µg/kg). Cooking temperature (β = 0.412, p < 0.001) and sodium nitrite use (β = 0.387, p = 0.002) were the strongest predictors of nitrosamine concentrations, with grilling producing the highest levels. Elevated nitrosamine levels in Tehran’s fast foods, particularly sausages, highlight the need for regulatory measures to limit nitrite use and optimize cooking practices. Future research should address potential confounding factors, such as pH or storage duration, and explore natural inhibitors like ascorbic acid to further mitigate nitrosamine formation. https://www.ehpr.ir/article_236539.html The widespread use of dishwashing liquids in households raises concerns about residual chemical compounds on kitchen utensils and their potential health implications. This study aimed to quantify the residues of sodium lauryl sulfate (SLS) and methylisothiazolinone (MIT) on ceramic plates, stainless steel cutlery, and glass tumblers, and to assess associated human exposure risks. A purposive sample of 100 households was selected, with 300 utensil samples analyzed using liquid chromatography–mass spectrometry (LC-MS) for residue quantification and exposure modeling to assess ingestion and dermal risks. Rinsing practices and water hardness were evaluated as influencing factors through multiple regression analysis. Results revealed significantly higher SLS (0.15 ± 0.04 µg/cm²) and MIT (0.03 ± 0.01 µg/cm²) residues on ceramic plates compared to stainless steel (0.11 ± 0.03 µg/cm² SLS; 0.02 ± 0.01 µg/cm² MIT) and glass (0.08 ± 0.02 µg/cm² SLS; 0.01 ± 0.005 µg/cm² MIT) (p < 0.05), attributed to ceramic’s rougher surface (Ra = 0.85 µm). Shorter rinsing durations (<10 seconds) and higher water hardness (>150 mg/L CaCO₃) increased residue retention by 25% and 15%, respectively (p < 0.05). Ingestion exposure was highest for ceramic plates (0.45 µg/kg/day SLS), with 2% of cases exceeding the acceptable daily intake (ADI) under worst-case scenarios, based on guideline values established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Dermal exposure remained negligible (hazard quotient <0.1). These findings indicate that while most exposures are within safe limits, the use of ceramic utensils and suboptimal rinsing practices pose low but notable risks. The study underscores the need for consumer education on effective rinsing and the development of formulations with enhanced reusability to minimize exposure. https://www.ehpr.ir/article_235895.html Unlined municipal landfills in semi-arid regions pose significant risks to adjacent rivers through leachate migration. This study quantifies downstream pollution from a >20-year-old landfill in Northwest Iran, assessing impacts on a 15-km perennial river segment. Water and sediment samples were analyzed across upstream, near-field, and far-field zones. Near-field water exhibited severe hypoxia (DO 3.2 mg/L), high organic loading (COD 98.6 mg/L), and elevated ammonium (NH₄⁺-N 14.7 mg/L), exceeding Iranian standards by up to 73.5× for ammonium. Heavy metals such as Pb (68.4 µg/L) and Cd (5.9 µg/L) surpassed WHO limits, while sediments showed moderate to heavy contamination (Igeo 2.4–2.8). Organic micropollutants, including DEHP and naphthalene, presented high ecological risks. Principal component analysis confirmed leachate as the dominant pollution source, and exponential decay models indicated 80–90% attenuation within 5 km downstream, although sediments retained legacy contaminants. The results define a 3-km high-risk buffer and underscore the need for urgent mitigation measures including liner installation, leachate collection, and riparian protection to safeguard water quality and aquatic ecosystems in semi-arid regions. https://www.ehpr.ir/article_238039.html This study was conducted to investigate the concentration of hazardous chemical compounds in children's toys available in Iran, addressing a significant data gap in regional market surveillance and the associated health risks for a vulnerable population. Using a stratified random sampling approach, 120 toys categorized as plastic, painted wood, rubber, and plush were collected from retail and online sources. Samples were analyzed via inductively coupled plasma mass spectrometry (ICP-MS) for heavy metals and gas chromatography–mass spectrometry (GC-MS) for organic compounds, including phthalates and flame retardants. The results identified clear material-specific contamination patterns. Rubber toys presented the highest concentrations of phthalates, with di(2-ethylhexyl) phthalate (DEHP) exceeding the European Union safety limit in 66.7% of samples. Painted wood toys showed elevated levels of lead and chromium, exceeding limits in 23.3% and 30.0% of samples, respectively. In contrast, plush toys demonstrated negligible chemical burdens. Statistical analysis confirmed significant differences between material categories, and a quantitative risk assessment indicated a potential health hazard (Hazard Quotient > 1) from exposure to lead in painted wood and DEHP in rubber toys. The conclusion underscores an urgent need for enhanced regulatory enforcement, focusing on high-risk material categories, alongside policies promoting supply chain transparency and the adoption of safer alternative materials in toy manufacturing to protect children's health. https://www.ehpr.ir/article_235897.html Considering the presence of high amounts of mercury in amalgam, the importance of mercury, and the problems it creates for the environment, including humans and other living organisms, this study was conducted to measure the amount of mercury in the wastewater of two dental clinics. We collected 30 wastewater samples from two dental clinics at the end of each day. Then the samples were digested by the USEPA 245.1 method. The samples were used for mercury determination by an atomic absorption spectrometer (Spectra AA 220 FS, Varian). The results showed that the amount of mercury in the wastewater resulting from the treatment of amalgam and others (68.7170 µg/L) was higher than in non-amalgam treatments (0.7290 µg/L). The amount of mercury in the wastewater samples was higher than the maximum allowed (0.002 mg/L). The relationship between the type of dental treatment and the amount of mercury was significant (P<0.0001). The amount of mercury in samples treated with amalgam was higher than in others. Moreover, the output of mercury from the clinic's wastewater was higher than the maximum amount recommended by the EPA. Therefore, it is necessary to monitor the mercury output of the clinics' wastewater and treat it.