Journal of Environmental Health Science and Engineering最新文献

Aedes aegypti is the proven vector of dengue fever, Zika, chikungunya, and yellow fever. In Iran, the first recorded sighting of Ae. aegypti dates back to 1920 and into the early 1950s. For 70 years, the species was not seen in the country. However, since 2018, reports have confirmed the presence of Ae. aegypti in various regions. It is now established in some areas of the southern provinces, including Hormozgan, Bushehr, and Sistan and Baluchistan. The appearance, disappearance, and subsequent re-emergence of Ae. aegypti in Iran, after a 70-year absence, are attributed to a combination of factors such as historical malaria control, infrastructure, globalization, urbanization, and climate change that is discussed in this study. This study underscores that the re-emergence of Ae. aegypti in Iran necessitates an urgent paradigm shift from reactive chemical-based control toward a proactive, integrated management framework. Ultimately, the long-term mitigation of dengue fever risk depends on the seamless integration of community-based environmental management with advanced biotechnological interventions.

In recent decades, concerns about microplastics increased as an important issue in the fields of environment and public health. This research evaluates the level of inhalation exposure to microplastics and examines their presence in the indoor air and nasal lavage fluid of beauty salon employees, both at home and during working hours in the salon. A total of 36 indoor air samples and 18 nasal lavage fluid samples were collected and analyzed. The results indicated the abundance of microplastics in the indoor air of beauty salons, and homes with mean values of 99.38 ± 4.1 and 36.61 ± 3.05 MPs/m3, respectively. Microplastics were also found in the nasal lavage samples of beauty salon workers and in homes, with the concentrations ranging from 12.33 to 23.78MP/ml and 9.32 to 20.12MP/ml, respectively. The average daily exposure to microplastics in homes, and beauty salons was calculated to be 211.55 ± 109 and 572.166 ± 238MPs/day, respectively. This research highlights the importance of reducing potential health hazards associated with microplastic exposure in these environments.

Healthcare hazardous materials represent an increasing challenge to public health, environmental sustainability, and healthcare resilience owing to the growing complexity of waste streams, emerging contaminants, and evolving regulatory requirements. Although numerous reviews have examined individual aspects of healthcare waste management, an integrated critical evaluation linking hazardous waste classification, risk assessment, treatment technologies, regulatory governance, and circular economy strategies remains lacking. This review addresses this gap by critically synthesizing current evidence on the sources, classification, exposure pathways, human and environmental risks, treatment technologies, regulatory frameworks, and sustainable management strategies for infectious, pharmaceutical, chemical, heavy metal, radioactive, plastic, and electronic healthcare wastes. The synthesis identifies inadequate source segregation, infrastructure deficiencies, inconsistent regulatory implementation, and the rapid emergence of medical plastics, antimicrobial residues, and healthcare electronic waste as the principal barriers to sustainable waste management. Comparative evaluation further demonstrates that effective source segregation, context-specific non-incineration treatment technologies, strengthened regulatory governance, digital waste monitoring, and resource recovery within a circular economy framework can substantially reduce environmental impacts, improve operational efficiency, and enhance resource sustainability. By integrating recent advances, identifying critical knowledge gaps, and proposing strategic priorities for research, policy, and healthcare practice, this review provides a comprehensive framework to support the transition towards safer, resource-efficient, and environmentally sustainable healthcare hazardous materials management.

Despite the global transition toward electrification, diesel engines continue to play a critical role in heavy-duty transportation, maritime operations, and decentralized power generation. Consequently, nitrogen oxides (NOₓ) emissions from diesel combustion remain a major contributor to urban air pollution and associated public health risks. However, research on diesel emissions, atmospheric chemistry, and pollution-related health effects has largely progressed in separate disciplines, limiting a comprehensive understanding of the pathway linking engine emissions to human health outcomes. This review addresses this gap using a structured Source–Pathway–Receptor framework that connects diesel combustion processes, atmospheric transformation of NOₓ, urban exposure dynamics, and biological health effects. The review synthesizes findings from combustion science, atmospheric chemistry, exposure assessment, epidemiology, and environmental health research to explain how diesel-derived NOₓ evolves from an engine-level pollutant into a complex urban health concern. The analysis highlights major factors influencing population exposure, including near-road pollution gradients, street-canyon effects, and discrepancies between laboratory certification and real-world driving emissions. Quantitative epidemiological evidence linking short-term and long-term NOₓ exposure with respiratory and cardiovascular outcomes is also discussed. In addition, the review evaluates current mitigation approaches, including in-cylinder combustion strategies, exhaust after-treatment technologies, fuel-based solutions, urban planning measures, and exposure-reduction policies. Future research priorities are identified to support stronger integration between emission-control technologies, air-quality management, and public health protection. Overall, the review provides an interdisciplinary perspective for understanding and mitigating diesel-related NOₓ emissions in modern urban environments.

The increasing prevalence of antibiotic-resistant bacteria (ARB) and resistance genes (ARGs) in wastewater poses a major public health challenge, particularly as conventional disinfection methods are often insufficient to fully eliminate resistant determinants. Simultaneously, microplastics (MPs) are emerging as persistent pollutants in aquatic systems, where they interact with microorganisms and may interfere with treatment processes. This study investigates the role of microplastic aging in modulating chlorination efficiency against ARB and ARGs in hospital wastewater. Polyethylene microplastics were subjected to controlled UV aging (0–15 days) and characterized using FTIR and AFM, revealing increased oxidation, surface roughness, and biofilm formation capacity after aging. Chlorination experiments showed that while pristine MPs only modestly reduced chlorine efficacy, aged MPs significantly impaired disinfection, resulted in more than 2 log10 higher bacterial survival following chlorination and 12–25-fold increases in ARG persistence. Moreover, biofilm assays demonstrated a nearly three-fold enhancement of microbial colonization on aged MPs compared with fresh ones. These findings highlight that environmental weathering transforms MPs into highly interactive substrates that shield bacteria, enhance gene persistence, and compromise conventional chlorination. The study underscores the importance of considering MP aging in water treatment risk assessments and suggests the need for improved strategies to mitigate the combined threats of microplastic pollution and antimicrobial resistance. Because elevated microplastic concentrations were employed to facilitate mechanistic evaluation under controlled laboratory conditions, the findings should be interpreted primarily as proof-of-concept evidence rather than a direct representation of environmental exposure scenarios.

Purpose

This study aimed to determine bisphenol A (BPA) concentration in fish muscle tissue (Liza abu and Brachirus orientalis) and water from five estuaries of Bandar-e Mahshahr, Khuzestan province, Iran.

Methods

40 water samples and 40 fish samples from two species were collected from the north coast of the Persian Gulf, Iran (Bandar-e Mahshahr). After preparing and extracting samples, BPA concentration was measured using gas chromatography-mass spectroscopy (GC-MS).

Results

The mean concentration of BPA in the muscle tissue of Liza abu and Brachirus orientalis was 4.15 ± 4.48 µg/kg and 3.65 ± 2.97 µg/kg, respectively. The mean concentration of BPA in the estuary’s water was equal to 0.035 ± 0.016 µg/L. BPA concentration in both fish species had a statistically significant difference (P = 0.002). The highest BPA concentration was observed in Jafari, Zangi and Ghazaleh estuaries and lowest concentrations were related to Darwish and Musa estuaries. The bioaccumulation of BPA was higher in Brachirus orientalis than in Liza abu. The results of the risk assessment showed that exposure to BPA due to the consumption of fish does not pose a significant risk to the health of consumers (HQ < 1). Considering the mean BPA concentration, the risk quotient (RQ) showed low ecological risk.

Conclusion

This study confirmed the presence of BPA in estuarine water and edible fish species of Bandar-e Mahshahr, with higher concentrations detected in Jafari, Zangi and Ghazaleh estuaries. Despite the low non-carcinogenic human health risk and ecological risk, regular monitoring of BPA is essential to prevent further accumulation and to protect both the aquatic ecosystem and public health in this industrialized coastal region.

Graphical abstract

Low-cost air quality sensors (LCS) provide high-resolution monitoring with affordability and real-time data but require performance evaluation and calibration due to probable lower accuracy compared to reference instruments and sensitivity to meteorological factors such as air relative humidity and temperature. Although most studies on low-cost sensors have been conducted in Europe and America, we did not find any study in regions like Iran, where air pollution levels and meteorological conditions differ significantly. In this study, performance evaluation and calibration of a low-cost particulate matter sensor were performed based on Federal Reference Method (FRM) and Federal Equivalent Method (FEM) in Tehran, from May 27, 2023, to August 19, 2024. Simple Linear Regression (SLR) and Multivariable Linear Regression (MLR) models were applied, validated via leave-one-out cross-validation (LOOCV). Results showed that LCS underestimated PM_2.5 and PM₁₀ concentrations in both warm and cold periods, with more pronounced and variable underestimation during warm months and more systematic, smaller underestimation in cold months. Underestimation was greater for PM₁₀ than PM_2.5 in both periods. Despite this, LCS measurements tracked reference instrument trends and responded well to concentration variations. Seasonal calibration was performed in addition to calibration for the entire sampling period due to varying LCS performance under different meteorological conditions. After SLR calibration model was applied the performance criteria were met only during the cold period for both PM_2.5 and PM₁₀. Applying the MLR calibration model improved accuracy, achieving acceptable performance for PM_2.5 throughout the entire sampling period and for PM₁₀ across the entire period and warm months, with R² values of 0.62–0.93 and normalized root mean square error (NRMSE) of 10.7–24.36%. This improvement resulted from incorporating air relative humidity, temperature, PM₁, and PM_2.5. Nevertheless, the performance of the sensor for PM_2.5 in the warm season proved satisfactory after calibration based only on the FEM. Overall, this study revealed notable variations in sensor performance under different meteorological conditions, emphasizing the need for seasonal calibration. The results show that, when LCS are properly calibrated using site-specific and multivariable regression models, they can serve as a reliable tool for high-resolution air quality monitoring. These findings support the broader adoption of LCS in national and local monitoring networks as well as in individual exposure assessment for epidemiological studies.

Purpose

The study addresses concerns regarding the potential increase in cancer cases due to the widespread use of high-resolution computed tomography (HRCT) during the COVID-19 pandemic.

Method

It estimates the Lifetime Attributable Risk (LAR) of certain cancers associated with HRCT in Fars Province, Iran. The estimation is based on a cross-sectional analysis conducted at Namazi Hospital from February 2020 to December 2022. The study employed the Imaging Performance Assessment of CT Scanners (ImPACT) to estimate organ doses. Additionally, it applied the Biological Effects of Ionizing Radiation (BEIR) Committee models to calculate the Lifetime Attributable Risk (LAR) of cancer. A sensitivity analysis was also conducted to project the anticipated increase in radiation-induced cancers in the region.

Results

Out of 1,411 patients 754 (53.4%) were male, and their ages ranged from 15 to 95 years. 28% (395) had HRCT more than once (2 to 8 times). The mean and 95% uncertainty limits (UL) for total LAR of lung, thyroid, esophagus, stomach, liver, breast and Leukemia were 90 (95% UL, 80 − 116), 24 (95% UL, 18 − 33), 32 (95% UL, 26–39), 9 (95% UL, 8–11), 5 (95% UL, 4–6), 217 (95% UL, 194–244) and 30 ( 95% UL, 10–101) per 100,000 persons, respectively. The excess cancer burdens from radiation in Fars are estimated at approximately 55 years for solid cancers and 58 years for leukemia, with the following rates: lung 1.2%, thyroid 0.8%, breast 0.7%, esophagus 2.8%, stomach 0.1%, liver 0.9%, and leukemia 0.5%.

Conclusion

The widespread use of HRCT during the COVID-19 pandemic, while crucial for diagnosis and management, may increase the risk of radiation-induced cancers, especially among younger individuals and women. Key factors influencing this risk include repeated scans, younger age at exposure, and sex differences. Although the overall cancer burden from HRCT is low compared to baseline cancer incidence, dose optimization and ultra-low-dose protocols are essential to minimize harm.

The risks associated with heavy metals (HMs) in oil are important for health. This study investigated and evaluated the concentration of HMs in oils examined in Iranian studies using a systematic review method. First, published articles were identified in the Science Direct, PubMed, Scopus, and Web of Science databases. The concentrations of HMs were extracted from reliable papers and subjected to risk assessments. This research utilized pooled concentration estimates from the selected articles, integrating them with a Monte Carlo probabilistic framework of 10,000 iterations to assess the uncertainty in both non-carcinogenic and carcinogenic risks for adults and children. After screening and quality control of the articles, 16 valid articles were identified. Rapeseed oil contained the highest amounts of Cd and Cu, soybean oil exhibited the highest level of Fe, corn oil had the lowest amount of As, and olive oil showed the highest levels of Ni, Zn, and Pb. The non-carcinogenic health risk assessment of HMs indicated that the hierarchy of metals, according to the Target Hazard Quotient (THQ) for the exposed population, was as follows: As > Cd > Pb > Ni > Zn > Fe > Cu. Furthermore, THQ of As, Cd, Cu, Fe, Ni, Pb, and Zn for adults were 2.947, 2.187, 0.115, 0.125, 1.321, 1.922, and 0.244, while THQ for children were 6.957, 5.200, 0.264, 0.292, 3.078, 4.414, and 0.566. The lifetime cancer risk (LTCR) for As, Cd, and Pb in Vegetable Oils (VOs) was within the permissible range. Moreover, the carcinogenic risk from As (4.361 × 10^− 3) was found to be 1.3 times higher than that of Cd (3.640 × 10^− 3) and 23.8 times higher than that of Pb (1.891 × 10^− 4). It can be concluded that due to the toxic effects of HMs in VOs, we should be more serious about reducing the risk and pollution levels in this region.

Objective

Based on the data from NHANES database, the relationship between the levels of metabolites of five organophosphate flame retardants (OPFRs) in adult urine and non-alcoholic fatty liver disease (NAFLD) was analysed to provide scientific foundation for the prevention and control of the development of NAFLD.

Methods

Data from 3287 adults (NHANES 2011–2018) were analysed, and the presence of NAFLD was determined based on the fatty liver index. R4.3.2 software was utilized to explore the correlation between the levels of metabolites of urinary OPFRs and NAFLD. The gWQS package in R was employed to perform weighted quantile sum regression analysis. Subjects were further stratified by sex to conduct binary Logistic regression analysis and weighted quantile sum regression analysis.

Results

In sex-stratified logistic regression analyses, higher urinary bis(1-chloro-2-propyl) phosphate (BCPP) levels were positively associated with NAFLD in men, with participants in the highest exposure category of log-transformed BCPP concentrations showing an increased risk of NAFLD (OR = 4.117, 95% CI: 1.160-14.606). No other urinary OPFR metabolites showed significant positive associations with NAFLD. WQS regression further suggested that BCPP, and to a lesser extent di-n-butyl phosphate (DBUP), were the main contributors to the OPFR mixture effect on NAFLD, particularly among men.

Conclusion

BCPP and DBUP may influence the development of NAFLD, and BCPP appears to be closely associated with NAFLD in men, suggesting that it may represent a potential risk factor for NAFLD.

Graphical abstract