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Background: Research on the relationship between bioaerosols and particulate matter (PM) concentrations is necessary, especially in hospitals where airborne bioaerosols can facilitate disease transmission. This study aimed to investigate the relationship between PM (PM2.5 and PM10) and bioaerosols, as well as the factors influencing them (temperature and humidity), in the air of liver transplant operating rooms (LTOR) at Imam Khomeini Hospital in Tehran. Methods: Bioaerosol samples (32 samples) were collected using the passive sampling method, employing open-door plates containing culture medium, during June and July of 2019. PM samples were obtained concurrently with bioaerosol samples using the GM8803 air quality detector, during four one-hour periods. Simple linear regression analysis was performed to determine the relationship between bioaerosol and PM concentrations. Results: It was revealed that the average concentrations of PM2.5 and PM10 were 17.8 (SD = 2.2) and 27.0 (SD = 2.6) μg/m3, respectively. Additionally, the average concentrations of bacterial and fungal bioaerosols were 2132 (SD = 837) and 550 (SD = 189.4) CFU/m2.h, respectively. Linear regression analysis demonstrated a strong correlation between bacterial bioaerosols and PM concentrations, whereas the relationship with fungal bioaerosols was relatively weaker. Conclusion: The findings of this study indicate that the indoor air in LTOR exhibits a higher level of microbial contamination than the recommended guidelines for high-risk environments. To improve the air quality in LTOR, it is recommended to implement periodic microbial monitoring, ensure the proper functioning of ventilation systems, and pay attention to their maintenance and operation.

Abstract Thorium biosorption by a green microalga, Chlorella Vulgaris, was studied in a stirred batch reactor to investigate the effect of initial solution pH, metal ion concentration, biomass dosage, contact time, kinetics, equilibrium and thermodynamics of uptake. The green microalgae showed the highest Th adsorption capacity at 45 °C for the solution with a thorium concentration of 350 mg L−1 and initial pH of 4. The amount of uptake raised from 84 to 104 mg g−1 as the temperature increased from 15 to 45 °C for an initial metal concentration of 75 mg L−1 at pH 4. Transformation Infrared Spectroscopy (FTIR) was employed to characterize the vibrational frequency changes for peaks related to surface functional groups. Also, the scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to determine the morphological changes and elemental analysis of the biosorbent before and after the sorption process. The Langmuir isotherm was in perfect agreement with the equilibrium empirical data of thorium biosorption and the highest sorption capacity of the Chlorella Vulgaris microalgae was determined as 185.19 mg g−1. Also, the results of kinetic studies show that the thorium biosorption process follows a pseudo-second-order kinetic model. The negative value of ΔG0 indicates spontaneity and the positive values of ΔH0 indicate the endothermic nature of the adsorption process.

Self-knowledge and its functionality has always been the focus of the scholars of humanities, especially in the field of philosophy. The objective of this paper is to study Imam Khomeini's approach to the subject of self-knowledge and its functions. Grounded theory has been applied in this qualitative study. The statistical population included all sources such as books, lectures, texts and letters of Imam Khomeini. The statistical sample included a total of 62 texts collected through purposeful method from different sources produced by Imam Khomeini related to self-knowledge. From source 48 onwards, the content within the text was repetitive and the data reached theoretical saturation. The data were analyzed through textual analysis within the framework of a conceptual model including the Causal conditions (causes and opportunities); Pivotal factors; Strategies; Underlying factors; Interference factors, facilitators (backers) and inhibitors (barriers), and ultimately consequences (results of self-knowledge). The findings show that a lifestyle consistent with true knowledge of the message of revelation and the program of primordial nature, turn of attention from acquired knowledge to intuitive knowledge and self-purification lead to self-knowledge. As a result of establishing a connection between knowledge of the self and the knowledge of the Lord, the potential talents inherent in human primordial nature are actualized. Hence, the rational soul will be attained and all the powers of the soul, including imagination, anger and lust, will surrender to the sane reason and the prophets’ messages and will turn to merciful armies, and eventually, the position of vicegerency of Allah and eternal happiness (felicity) will be achieved.

Background: Numerous investigations have explored variations in vertical air pollutant concentrations, yielding diverse findings. So, we have conducted this systematic review to gain a more comprehensive understanding of the vertical distribution of air pollutant concentrations (PM2.5, PM10, NOX, and NO2) and the influencing factors. Methods: Relevant studies were identified by searching the three central electronic databases, PubMed, Web of Science, and Scopus, from the beginning of 2000 to the end of 2023. This study included original articles published in English that examine the pollutant concentration variations below 500 m. Finding: Of 3614 articles, 57 studies met our criteria. Our findings showed a decline in PM2.5 and NOX concentrations as altitude increased, while NO2 concentrations exhibited an increase. Conversely, no statistically significant relationship was identified between altitude and PM10 concentrations. The regression analysis yielded coefficients for the relationship between concentration and altitude (0–500 m) as follows: PM2.5 (−0.11), PM2.5/PM10 (0.0008), NOX (−0.11), and NO2 (0.13). Conducting additional research on this topic and investigating the impact of meteorological parameters on pollutant concentrations at different altitudes enhances our understanding of the vertical distribution of pollutant concentrations.

The aim of this study was to design and test a model of some antecedents of social anxiety. This descriptive research used the structural equation modeling (SEM) method. The statistical population was included all the students of Ahvaz Jundishapur University of medical sciences in 2020-2021, of which 581 were selected by multistage cluster sampling method. The tools were Social Phobia Inventory, Shyness Scale, Shame Scale, Behavioral Inhibition system, Anger Expression Inventory and Depression Scale. Data were analyzed by SEM method. Fit indices showed that the research model had a good fit with the data. The effect of the coefficient of direct standard paths of behavioral inhibition, shyness, depression, shame with social anxiety were significant but the direct coefficient for anger on social anxiety was not significant. Also, the findings confirm the significant indirect relationships of behavioral inhibition and shyness with the mediating roles of depression and shame. The research findings showed the importance of behavioral inhibition and shyness as influencing factors on students' social anxiety with the mediation of depression and shame. According to the role of factors in the research model, it can be used in designing the treatment of students' social anxiety.

Objectives: This study aimed to assess the impact of wearing N95 and surgical masks on carbon dioxide (CO2) concentrations during various activity levels, to understand the implications for mask use in different settings, especially in light of the COVID-19 pandemic. Study design: Systematic Review and Meta-Analysis. Methods: A systematic review was conducted, retrieving 6798 articles from PubMed, Web of Science, and Scopus databases. Twenty-nine articles met the inclusion criteria. Mask types were categorized into N95 and surgical masks, while activities were classified as low, medium, and high. Results: The meta-analysis revealed CO2 concentrations (mmHg) for different scenarios: No mask (37.91, 95 % CI: 36.46, 39.35), N95-low (36.83, 95 % CI: 33.57, 40.10), N95-moderate (37.85, 95 % CI: 36.51, 39.20), N95-high (39.51, 95 % CI: 38.00, 41.02), N95 with exhalation valve (35.82, 95 % CI: 32.89, 38.75), N95 without exhalation valve (38.45, 95 % CI: 37.10, 39.81), surgical mask-low (38.31, 95 % CI: 34.48, 42.14), surgical mask-moderate (35.05, 95 % CI: 31.12, 38.97), surgical mask-high (36.07, 95 % CI: 34.18, 37.96). Conclusions: Our findings indicate that N95 masks lead to higher CO2 accumulation during various activities compared to surgical masks. Moreover, surgical masks exhibit higher CO2 concentrations during low activity compared to moderate and high activities. Notably, CO2 concentrations are higher in N95 masks without an exhalation valve compared to those with a valve. No significant difference was observed between not wearing a mask and wearing either N95 or surgical masks in terms of CO2 accumulation. These results provide important insights for mask selection and usage recommendations in different scenarios.

Background Coronary heart disease (CHD) is the most prevalent type of cardiovascular disease in Iran. This study aims to investigate the estimation and determinants of direct hospitalisation cost for patients with CHD in Iranian hospitals.Methods We identified patients with CHD in Iran in 2019–2020. Data were gathered from the Iran Health Insurance Organisation information systems and the Ministry of Health and Medical Education. This was a cross-sectional prevalence-based study. Generalised linear models were used to find the determinants of hospitalisation cost for patients with CHD. A total of 86 834 patients suffering from CHD were studied.Results Mean hospitalisation cost per CHD patient was US$382.90±US$500.72 while the mean daily hospitalisation cost per CHD patient was US$89.71±US$89.99. In-hospital mortality of CHD was 2.52%. Hospitalisation accommodation and medications had the highest share of hospitalisation costs (25.59% and 22.63%, respectively). Men spent 1.12 (95% CI 1.11 to 1.13) times more on hospitalisation costs compared with women, and individuals aged 60 to 69 had hospitalisation costs 1.04 (95% CI 1.02 to 1.06) times higher than those in the 0–49 age range. Patients insured by the Iranian Fund have significantly higher costs 1.17 (95% CI 1.14 to 1.19) than the Rural fund. Hospitalisation costs for patients with CHD who received surgery and angiography were significantly 2.36 (95% CI 2.30 to 2.43) times higher than for patients who did not undergo surgery and angiography.Conclusion Applying CHD prevention strategies for men and the middle-aged population (50–70 years) is strongly recommended. Prudent use and prescribing of medications will be helpful to reduce hospitalisation cost.

Air contamination is one of the serious problems for the environment and the health of society. Air contamination risk assessment, health effects assessment tools are used to identify the place and time of public health effects and risk prevention strategies to reduce negative health effects. Considering that there may be a relationship between factors affecting risk, in this study, interactions between them are investigated using Fuzzy Decision Test and Experimental Evaluation Method (fuzzy DEMATEL). The cause of the health air contamination risk in an industrial area are the activity of industrial complexes and port (D+R=45.98, D-R=2.09) and the presence of hydrogen sulfide (46.82, 2.61), benzene (50.87, 2.87), sulfur dioxide (43.87, 4.32) and PM10 (53.51, 5.63) and the effects of these factors will affect the amount of carbon monoxide (39.56, -4.47), ozone (38.80, -4.20), nitrogen dioxide (50.33, -1.62) and PM2.5 (44.18, -1.26). Hospitals and nursing homes (49.01, -2.58), schools (50.99, -0.59), storage and industrial facilities, roads (45.72, -0.59), urban core (51.38, -0.55) and Natural zones, agriculture and waterways (48.86, -0.17) are affected by other factors. Population density is also affected by cause factors. Population density has a two-way relationship with PM2.5. The main human and social factors include GDP per capita and urbanization rate. Hydrogen sulfide has a one-way relationship with population density. People who work in certain industries may be exposed to higher amounts of hydrogen sulfide than the general population. These industries include the production of rayon textiles, pulp and paper factories, oil and natural gas drilling operations, and wastewater treatment plants. Therefore, by controlling the activity of industrial complexes, port and the amounts of hydrogen sulfide, benzene, sulfur dioxide and PM10 in the ambient air can be prevented from the effects after that.

ObjectivesWe evaluated studies that used the World Health Organization’s (WHO) AirQ and AirQ+ tools for air pollution (AP) health risk assessment (HRA) and provided best practice suggestions for future assessments.MethodsWe performed a comprehensive review of studies using WHO’s AirQ and AirQ+ tools, searching several databases for relevant articles, reports, and theses from inception to Dec 31, 2022.ResultsWe identified 286 studies that met our criteria. The studies were conducted in 69 countries, with most (57%) in Iran, followed by Italy and India (∼8% each). We found that many studies inadequately report air pollution exposure data, its quality, and validity. The decisions concerning the analysed population size, health outcomes of interest, baseline incidence, concentration-response functions, relative risk values, and counterfactual values are often not justified, sufficiently. Many studies lack an uncertainty assessment.ConclusionOur review found a number of common shortcomings in the published assessments. We suggest better practices and urge future studies to focus on the quality of input data, its reporting, and associated uncertainties.

Intraventricular hemorrhage (IVH) in children is uncommon and it comprises about 3% of spontaneous cerebral hemorrhages. Intraventricular hemorrhage occurs mostly simultaneously with cerebral hemorrhage or subarachnoid hemorrhage. Primary IVH occurs mostly in adults; however, it has been reported since the age of nine. Acute hemorrhage may cause sudden or thunderclap headaches, decreased level of consciousness, and neck stiffness along with focal neurological deficits and convulsions and can be rapidly fatal. An eight-year-old girl with no history of underlying disease was referred to the Emergency Department of Hazrat Masoumeh Hospital, Qom, Iran, with sudden headache, vomiting, and visual disturbances. There, she had generalized seizures, and after entering the Pediatric Intensive Care Unit, she suffered from irregular breathing and bilateral mydriasis of the pupils without reaction to light. In the brain computed tomography scan, bilateral IVH and hydrocephalus were seen. Finally, the patient was declared brain-dead and died four weeks later. Sudden spontaneous IVH in children is rare and creates potentially dangerous and emergency conditions for them. To manage the treatment of these patients, attention should be paid to the three principles of stopping bleeding, controlling hydrocephalus, and treatment of intracerebral pressure. Early treatment prevents severe brain complications and death. For patients with headaches, vomiting, and restlessness, we must consider careful neurological examinations.The purpose of presenting this article was to diagnose and manage emergency treatment in children with cerebral hemorrhage and intracerebral pressure control to prevent neurological complications and death.

Abstract This study simulates the separation of stable Neon isotopes in a transient square cascade using the Crank–Nicolson method and the q-iteration method. The simulations show that each isotope has an optimal value in either the product or waste streams at a specific time, which affects the cost of separation. The results demonstrate that the optimal separation time for Ne-20 increases with the feed concentration and is influenced by the unit separation factor. Depending on the feed concentration and separation parameter, Ne-21 may be enriched in either the product or waste stream. The optimal separation time for Ne-22 is the maximum operation time and is not affected by changes in feed concentration or unit separation factor. Calculating the optimal separation time is crucial for obtaining target isotopes with specific purity at a designated time, depending on their intended applications.

Background: In recent years, new findings on the relationship between human health and air pollutants have emerged, underscoring the necessity for appropriate site selection of air monitoring stations. Methods: This analytical-cross-sectional study aimed to compare the concentration levels of PM10 and PM2.5, as measured by weight method, with data collected from an air quality monitoring station (AQMS) in Tehran. Initially, data were collected from the Tarbiat Modares AQMS. The accuracy of this data was then evaluated using a high-volume sampler and Grimm dust monitor situated approximately 200 meters away from the Tarbiat Modares station. The study period was between June 2017 and October 2017, and the frequency of sampling was every six days according to the instructions. Results: The results revealed that the average concentration levels of PM10, as measured during the sampling period by the high-volume sampler, the Grimm device, and the air quality measurement station, were 143.54 ± 33.84, 70.95 ± 7.06, and 110.06 ± 27.08 μg.m-3, respectively. The highest daily concentration of PM10 was recorded by the high-volume sampler device at 197.12 μg.m-3. Conclusion: This study found a weak correlation between the aerosol concentration data obtained from the monitoring station and those obtained from the Grimm device and the high-volume sampler. Therefore, it is crucial to ensure the quality control and assurance of data collected from monitoring stations for accurate decision-making and planning.

During automated negotiations, intelligent software agents act based on the preferences of their proprietors, interdicting direct preference exposure. The agent can be armed with a component of an opponent’s modeling features to reduce the uncertainty in the negotiation, but how negotiating agents with a single-peaked preference direct our attention has not been considered. Here, we first investigate the proper representation of single-peaked preferences and implementation of single-peaked agents within bidder agents using different instances of general single-peaked functions. We evaluate the modeling of single-peaked preferences and bidders in automated negotiating agents. Through experiments, we reveal that most of the opponent models can model our benchmark single-peaked agents with similar efficiencies. However, the accuracies differ among the models and in different rival batches. The perceptron-based P1 model obtained the highest accuracy, and the frequency-based model Randomdance outperformed the other competitors in most other performance measures.

Monte Carlo (MC) techniques are regarded as an accurate method to simulate the dose calculation in radiotherapy for many years. The present paper aims to validate the simulated model of the 6-MV beam of OMID linear accelerator (BEHYAAR Company) by EGSnrc codes system and also investigate the effects of initial electron beam parameters (energy, radial full width at half maximum, and mean angular spread) on dose distributions. For this purpose, the comparison between the calculated and measured percentage depth dose (PDD) and lateral dose profiles was done by gamma index (GI) with 1%-1 mm acceptance criteria. MC model validating was done for 3 cm × 3 cm, 5 cm × 5 cm, 8 cm × 8 cm, 10 cm × 10 cm, and 20 cm × 20 cm field sizes. To study the sensitivity of model to beam parameters, the field size was selected as 10 cm × 10 cm and 30 cm × 30 cm. All lateral dose profiles were obtained at 10 cm. Excellent agreement was achieved with a 99.2% GI passing percentage for PDD curves and at least 93.8% GI for lateral dose profiles for investigated field sizes. Our investigation confirmed that the lateral dose profile severely depends on the considered source parameters in this study. PDD only considerably depends on the initial electron beam energy. Therefore, source parameters should not be specified independently. These results indicate that the current model of OMID 6-MV Linac is well established, and the accuracy of the simulation is high enough to be used in various applications.

Background and aims: Mood disorders include major depression and bipolar disorder. Treatment adherence and health literacy are very important in these patients because they may affect their quality of life, performance, and recovery. Therefore, this study aims to determine the level of treatment adherence and its relationship to health literacy in patients with mood disorders. Methods: This cross-sectional-correlation study was conducted on 120 patients with mood disorders in 2021-2022. Data were collected using the treatment adherence questionnaire of Ziaee et al and the Health Literacy of Iranian Adults (HELIA) questionnaire. Finally, the collected data were analyzed in SPSS-16 software. Results: Findings showed that patients with mood disorders had moderate treatment adherence (51.53±8.31) and insufficient health literacy (61.31±15.91). The results indicated that treatment adherence had a significant relationship with health literacy in patients with mood disorders (P

Abstract In the current research work, the flow behavior of a liquid–liquid extraction (LLE) process in a serpentine microchannel was analyzed. The simulation was performed using a 3D model and the results were found to be consistent with experimental data. The impact of the flow of chloroform and water on the flow model was also examined. The data indicate that once the aqua and organic phases flow rates are low and similar, a slug flow pattern is observed. However, as the overall flow rate raises, the slug flow transforms into parallel plug flow or droplet flow. An increment in the aqua flows while maintaining a constant organic phase flow rate results in a transition from slug flow to either droplet flow or plug flow. Finally, the patterns of flow rate in the serpentine micro-channel were characterized and depicted. The results of this study will provide valuable insights into the behavior of two-phase flow patterns in serpentine microfluidic devices. This information can be used to optimize the design of microfluidic devices for various applications. Furthermore, the study will demonstrate the applicability of CFD simulation in investigating the behavior of fluids in microfluidic devices, which can be a cost-effective and efficient alternative to experimental studies.

To evaluate the prevalence of positive serum antinuclear antibody (ANA) in children with epilepsy using three major antiepileptic drugs (phenytoin, carbamazepine and ethosuximide), 60 children under 18 years with epilepsy who were referred to pediatric neurology clinic or had admitted to neurology ward in Children Hospital in Tehran, Iran, were entered our study. They had been treated with one of the three antiepileptic drugs (carbamazepin, phenytoin, ethosuximide) with suitable dose for at least one month. The patients were divided into two groups according to the classification of the International League Against Epilepsy (ILAE): drug-resistant and drug-responsive. We studied the epidemiological and clinical characteristics and also serum ANA of the patients in both groups. In this research, we studied ANA in 60 epileptic children. 30 patients were diagnosed with drug resistant epilepsy and the other 30 were drug responsive. None of them showed the clinical manifestations of lupus erythematosus. As a whole, 7 patients (11.7%) were ANA-positive, 6.7% of drug resistant and 16.7% of drug responsive group showed this finding. There was no relationship between drug resistancy and ANA according to statistical studies (P=0.21). Although in our study, epidemiological and clinical data of the patients was reported in two separate groups of resistant or responsive to antiepileptic drugs, and no meaningful statistical difference was found between these two groups. Overally in our study, the prevalence of positive ANA in patients receiving antiepileptic drugs was less in comparison with previous studies and was more common in males. Finally, we suggest a more comprehensive and extensive study with more cases and further follow-up period in order to find the cause of immunological reactions to antiepileptic drugs in children with epilepsy.

The cultural rituals of any society are the birth certificates of that society’s culture, history, religion, and ethics. These rites and rituals are an important factor in fostering cohesion and unity among the people of a society who gather together in various ceremonies. Mourning ceremonies and rituals vary in different provinces, cities, and villages across the country, particularly during the first decade of Muharram. Iran is considered one of the inheritors of world culture due to its diverse and rich cultural rituals. The purpose of this research is to do a comparative and documented study of Muharram rituals in these two provinces so that by revealing the manifestations of cultural rituals and their differences and similarities, we can reach the deep and rich layers of the culture of these two provinces. This research intends to investigate the differences and similarities between the rituals of the first decade of Muharram and their cultural differences in the two provinces of East Azarbaijan and Khuzestan, using a descriptive-comparative study method. These two provinces have a deep cultural and religious background and an ancient civilization. The results of this research show that despite the great similarity in the performance of Muharram rituals in the two provinces in question, the diversity of mourning rituals is also visible in these two provinces. The varieties and differences are closely related to cultural, climatic, and linguistic differences in these two provinces. These two provinces’ people have chosen to mourn in accordance with their religion, vegetation, culture, and language. The results of this research show that, in addition to these differences, the common points of this cultural ritual in the two provinces are the love of the Prophet’s family and devotion to Ashura culture.

Abstract Combining electrocoagulation with another process is a potential strategy for increasing the efficiency of water and wastewater pollutant removal. The integration of advanced oxidation processes (AOPs) and electrocoagulation (EC) demonstrates improved performance. The mechanism of the EC combined with ozone (O3), hydrogen peroxide (H2O2), sulfate radicals, electrooxidation (EO), Fenton/electro-Fenton, and UV is discussed. This review sheds light on EC-AOP hybrid processes in terms of their mechanisms, development, challenges, and their potential application for the removal of contaminants of emerging concern (CECs). The majority of the articles claimed improved performance of the EC process when combined with AOP as a pre-treatment, especially in terms of removing recalcitrant contaminants. For instance, the integrated EC-Fenton/photo-Fenton processes have been shown to be a promising treatment to virtually complete removal of the phenolic compounds in oil refinery wastewater. In EC-EO process, boron doped diamond (BDD) anode, despite being costly electrode, has the highest oxidation potential and is therefore the most suitable type for the mineralization of organic pollutants. PFASs are more effective at being removed from water through zinc and Ti4O7 electrodes in EC-EO treatment. Furthermore, the peroxone and synergistic effects between O3 and coagulants played almost equal dominant role to removal of ibuprofen using hybrid EC-O3. However, enough data for conducting these integrated processes at industrial scale or with real wastewaters do not exist, and so there is a lack for comprehensive and systematic approaches to address complexity of such systems. Although a great number of papers were focused on the degradation of effluents from different industries, viruses, and pharmaceuticals, there is not sufficient research in terms of the removal of herbicides, pesticides, microplastics, and micropollutants.

The thermal efficiency of the nanofluid flow along the 180-elbow pipe is investigated under effects of double source of non-uniform magnetic field. To model the nanofluid stream with double magnetic sources, computational fluid dynamic is used. Effects of magnetic intensities and velocity of nanofluid on the hydrodynamic of the chosen model is also investigated in this research. The results of simulation indicate that the vortices are generated near the magnetic field and these vortices extend the thermal layer into the main stream and consequently, thermal efficiency of nanofluid stream is enhanced in 180-degree elbow. The results of various magnetic intensities also show that the increasing the magnetic intensities changes the location of maximum heat transfer from 1st magnetic source to 2nd one.

Fine particulate matter (PM2.5) air pollution is a leading contributor to the global burden of cardiovascular disease (CVD). One important underlying mechanism is an increase in blood pressure (BP). A growing number of studies have reported a beneficial effect of portable air cleaners (PACs) on systolic and diastolic BP; SBP and DBP. We conducted an updated systematic review and meta-analysis of studies using true versus sham mode filtration reporting the effects on BP. Of 214 articles identified up to February 5, 2023, seventeen (from China, USA, Canada, South Korea and Denmark) enrolling approximately 880 participants (484 female) met the inclusion criteria for meta-analyses. Aside from studies conducted in China, research on PACs and BP has been conducted in relatively low pollution settings. Mean indoor PM2.5 concentrations during the active and sham mode purification were 15.9 and 41.2 µg/m3, respectively. The mean efficiency of PACs against indoor PM2.5 was 59.8 % (ranging from 23 % to 82 %). True mode filtration was associated with a pooled mean difference of − 2.35 mmHg (95 % confidence interval [CI]: − 4.5, − 0.2) and − 0.81 mmHg (95 % CI: − 1.86, 0.24) in SBP and DBP, respectively. After removing the studies with high risk of bias, the magnitude of the pooled benefits on SBP and DBP increased to − 3.62 mmHg (95 % CI: − 6.69, − 0.56) and − 1.35 mmHg (95 % CI: − 2.29, − 0.41), respectively. However, there are several barriers to the use of PACs, specifically in low- and middle-income countries (LMICs), such as the initial purchase cost and filter replacements. There may be several avenues to help overcome these economic burdens and improve cost effectiveness, such as implementing government or other subsidized programs to distribute PACs targeting vulnerable and higher-risk individuals. We propose that environmental health researchers and healthcare providers should be better trained to educate the public regarding the use of PACs to reduce the impacts of PM2.5 on cardiometabolic diseases globally.