Estimation of PM2.5 using high-resolution satellite data and its mortality risk in an area of Iran.

Satellite-based exposure of fine particulate matters has been seldom used as a predictor of mortality. PM2.5 was predicted using Aerosol Optical Depths (AOD) through a two-stage regression model. The predicted PM2.5 was corrected for the bias using two approaches. We estimated the impact by two different scenarios of PM2.5 in the model. We statistically found different distributions of the predicted PM2.5 over the region. Compared to the reference value (5 µg/m3), 90th and 95th percentiles had significant adverse effect on total mortality (RR 90th percentile:1.45; CI 95%: 1.08-1.95 and RR 95th percentile:1.53; CI 95%: 1.11-2.1). Nearly 1050 deaths were attributed to any range of the air pollution (unhealthy range), of which more than half were attributed to high concentration range. Given the adverse effect of extreme values compared to the both scenarios, more efforts are suggested to define local-specific reference values and preventive strategies.

Effect of PM2.5 exposure on adhesion molecules and systemic nitric oxide in healthy adults: The role of metals, PAHs, and oxidative potential.

Since there is limited evidence on the impact of PM2.5 content on cardiovascular biomarkers, we conducted a cross-sectional study on 89 healthy adults from October 12 to November 21, 2021. We measured daily PM2.5 in two distinct regions during different time windows: a high-traffic urban area and an industrial suburb. The concentrations of metals, PAHs, and oxidative potential (OP) were determined using ICP-MS, GC-MS, and dithiothreitol (DTT), respectively. Systemic biomarkers, including NO, sICAM-1, sVCAM-1, MDA, and CRP, were quantified in each subject simultaneously. A generalized linear model was used to examine the association between PM2.5 toxicity and each health endpoint. Our findings indicated that daily PM2.5 concentrations exceeded the WHO-recommended level by approximately sevenfold. We found that PM2.5 exposure was associated with adverse cardiovascular outcomes. Moreover, exposure to PM2.5 mass, total PAHs, and certain trace metals (Ni, Fe, V, As, and Pb) resulted in a decline in serum NO levels. At lag 3, exposure to PM2.5 mass resulted in a significant decrease in NO levels [1.32% (95% CI: -2.27, -0.12)] and total PAHs [2.05% (95% CI: -3.93, -0.12)]. In contrast, OP exhibited a mild correlation with NO level increases. Positive associations were observed between PM2.5 and its chemical constituents (PAHs, As, Cu, OP) and adhesion molecules at different lag times. An increase of 0.16 ppb in PAH concentrations at an interquartile range was associated with a 4.74% decline (95% CI, -7.80, -0.55) in the sVCAM-1 level. However, our study did not reveal any significant trend between pollutants and other biomarkers (sICAM-1, MDA, and CRP). Consequently, our findings suggest that different PM2.5 chemical compositions exhibit diverse behavior in biological responses.

Suspended particulate matter promotes epithelial-to-mesenchymal transition in alveolar epithelial cells via TGF-ß1-mediated ROS/IL-8/SMAD3 axis.

Epidemiological evidence presents that dust storms are related to respiratory diseases, such as pulmonary fibrosis (PF). However, the precise underlying mechanisms of SPM-elicited adverse effects still need to be investigated. Epithelial-mesenchymal transition (EMT) process is a characteristic of PF. We discussed whether suspended particulate matter (SPM) is involved in EMT induction via transforming growth factor-ß1 (TGF-ß1). In this study, a detailed elemental analysis (55 elements), particle size, and morphology were determined. To investigate the toxicity of SPM, an MTT test was performed to detect cell viability. Next, A549 cells were exposed to selected concentrations of SPM (20 and 40 µg/mL) for single and repeated exposures. The DCFH-DA assay showed that exposure to SPM could produce reactive oxygen species (ROS). The ELISA assay demonstrated increased levels of interleukin-8 (IL-8) and TGF-ß1 in the supernatant. Western blot was used to detect the expression of proteins associated with EMT and the SMAD3-dependent pathway. Results of western blot demonstrated that E-cadherin was reduced, whereas p-SMAD3, vimentin, and α-smooth muscle actin were elevated. Our findings indicated that SPM triggered EMT by induction of oxidative stress, inflammation, and the TGF-ß1/SMAD3 pathway activation.

Atmospheric pollution by potentially toxic elements: measurement and risk assessment using lichen transplants.

The lichen Usnea articulata collected from an unpolluted area was exposed for 6 months at 26 sites for the sample chosenusing a stratified random design, and the content of potentially toxic elements (PTEs) including As, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sn, V, and Zn, was assessed using ICP-MS. The health risk for both adults and children was then calculated using the PTEs concentrations. The results showed that despite the hostile urban conditions, transplanted lichens depicted clear deposition patterns of airborne PTEs, mostly associated with industrial sites, where As and other elements showed remarkably high values. The cumulative hazard index was below the risk threshold, both for adults and children. For the entire population (particularly children) residing in areas surrounding industrial sites, As and Cr appeared to be potentially carcinogenic elements.

The impact of COVID-19 pandemic lockdowns on air quality index: a systematic review.

During the outbreak of the novel coronavirus disease 2019 (COVID-19), many countries implemented lockdown policies to control its transmission. These restrictions provided an opportunity to rest and recover the environment. This systematic review (SR) aimed to evaluate the impact of COVID-19 lockdowns on the Air Quality Index (AQI) in countries worldwide. ScienceDirect and PubMed were searched using relevant keywords to identify studies published until March 2020. Overall, 20 studies were included in the SR based on the eligibility criteria. The results show that COVID-19-related lockdown policies positively affect AQI by restricting air-polluting activities, such as transportation, industry, and construction. However, it is important to note that these policies are ineffective in controlling sources of natural air pollution and local dust. The findings of this study emphasize the need for policymakers to approve legislation limiting the sources of air pollutants.

The Prevalence of Virulence Factors among ESBLs-Producing Klebsiella pneumoniae Isolated from Khorramabad Hospitals, Iran.

BACKGROUND: Klebsiella pneumoniae is one of the opportunistic bacteria that cause hospital infections. Various virulence factors are involved in its pathogenesis. The purpose of our study was to investigate the prevalence of virulence factor genes entB, mrkD, magA, kfu, iutA, rmpA, ybtS, and k2 among ESBLs-producing Klebsiella pneumoniae isolated from clinical samples of Khorramabad hospitals in Iran. METHODS: In this descriptive, analytical study, the extended-spectrum ß-lactamases (ESBLs) screening phenotypic test was performed by disc diffusion method, and virulence factor genes were detected by PCR method for Klebsiella pneumoniae isolates. Finally, the obtained data were statistically analyzed by SPSS software (version 21) using the chi-squared test. RESULTS: One hundred and ten K. pneumoniae strains were isolated from urine 69 (62.7%), sputum 16 (14.5%), blood 10 (9.1%), wound 9 (8.2%), tissue 3 (2.7%), body fluids 2 (1.8%), and catheter 1(0.9%). Based on an ESBL screening phenotypic test, 57 (51.8%) K. pneumoniae isolates were ESBLs-producing. Among 57 ESBLs-positive K. pneumoniae, the occurrence of mrkD, entB, ybtS, iutA, kfu, k2, and rmpA genes were 88 (80%), 87 (79.1%), 65 (59.1%), 42 (38.2%), 19 (17.3%), 5 (4.5%), 3 (2.7%), and 2 (1.8%), respectively. CONCLUSIONS: The findings of this study revealed, there is no significant association between the occurrence of virulence genes or source of samples with production of ESBLs among K. pneumoniae isolates.

Efflux Pump and Biofilm Inhibitory Activity of Nanoparticles in Acinetobacter Baumannii: a Systematic Review.

BACKGROUND: Acinetobacter baumannii produce biofilm and efflux pumps. This systematic review study aimed to provide new strategies to inhibit the efflux pumps and biofilm in A. baumannii using nanoparticles. METHODS: In this research, analyses from 2000 to February 24, 2022, were performed by the Statement of Preferred Reporting Items for Systematic Reviews (PRISMA). Keywords include Acinetobacter baumannii (A. baumannii) AND (biofilm) AND (anti-biofilm activity) AND (nanoparticles) AND (solid lipid NPS) AND (lipid nanocarriers), and in other searches include Acinetobacter baumannii (A. baumanni) AND (efflux pumps) AND (nanoparticles) AND (solid lipid NPS) AND (lipid nanocarriers). Searches were conducted in English databases, including Science Direct, PubMed, Scopus, Ovid, and Cochrane. RESULTS: At first, 136 studies were extracted, but after removing duplicates, 116 cases remained for further analysis. After evaluating the title and abstract of each study, 95 unrelated studies were excluded. The remaining 25 studies were reviewed based on full texts. Considering the inclusion/exclusion criteria, 19 studies were selected. In this study, metal nanoparticles were the most used nanoparticles for anti-biofilm and efflux pump purposes, and among these nanoparticles, silver nanoparticles (AgNPs) contributed the most. CONCLUSIONS: The present study shows that nanoparticles have potential and significant effects in inhibiting biofilm and efflux pumps in A. baumannii isolates, which researchers can consider in light of the increasing prevalence of antibiotic resistance.

Contaminant occurrence, distribution and ecological risk assessment of phthalate esters in the Persian Gulf.

Due to the increasing population of the world, the presence of harmful compounds, especially phthalate esters (PAEs), are one of the important problems of environmental pollution. These compounds are known as carcinogenic compounds and Endocrine-disrupting chemicals (EDCs) for humans. In this study, the occurrence of PAEs and the evaluation of its ecological risks were carried out in the Persian Gulf. Water samples were collected from two industrial sites, a rural site and an urban site. Samples were analyzed using magnetic solid phase extraction (MSPE) and gas chromatography-mass spectrometry (GC/MS) technique to measure seven PAEs including Di(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), diethyl phthalate (DEP), dibutyl phthalate (DBP), Dimethyl phthalate (DMP), di-n-octyl phthalate (DNOP), and Di-iso-butyl phthalate (DIBP). The BBP was not detected in any of the samples. The total concentration of six PAEs (Σ6PAEs) ranged from 7.23 to 23.7 µg/L, with a mean concentration of 13.7µg/L. The potential ecological risk of each target PAEs was evaluated by using the risk quotient (RQ) method in seawater samples, and the relative results declined in the sequence of DEHP >DIBP > DBP > DEP > DMP in examined water samples. DEHP had a high risk to algae, crustaceans and fish at all sites. While DMP and DEP showed lower risk for all mentioned trophic levels. The results of this study will be helpful for the implementation of effective control measures and remedial strategies for PAEs pollution in the Persian Gulf.

Effects of Gallic Acid on Memory Deficits and Electrophysiological Impairments Induced by Cerebral Ischemia/Reperfusion in Rats Following Exposure to Ambient Dust Storm.

We aimed to investigate the probable protective effects of gallic acid (GA) on cognitive deficits, hippocampal long term potentiation (LTP) impairments, and molecular changes induced by cerebral ischemia/reperfusion (I/R) in rats following exposure to ambient dust storm. After pretreatment with GA (100 mg/kg), or vehicle (Veh) (normal saline, 2 ml/kg) for ten days, and 60 minutes' exposure to dust storm including PM (PM, 2000-8000 g/m3) every day, 4-vessel occlusion (4VO) type of I/R was induced. Three days after I/R induction, we evaluated behavioral, electrophysiological, histopathological, molecular and brain tissue inflammatory cytokine changes. Our findings indicated that pretreatment with GA significantly reduced cognitive impairments caused by I/R (P < 0.05) and hippocampal LTP impairments caused by I/R after PM exposure (P < 0.001). Additionally, after exposure to PM, I/R significantly elevated the tumor necrosis factor α content (P < 0.01) and miR-124 level (P < 0.001) while pre-treatment with GA reduced the level of miR-124 (P < 0.001). Histopathological results also revealed that I/R and PM caused cell death in the hippocampus CA1 area (P < 0.001) and that GA decreased the rate of cell death (P < 0.001). Our findings show that GA can prevent brain inflammation, and thus cognitive and LTP deficits caused by I/R, PM exposure, or both.

The protective effect of p-Coumaric acid on hepatic injury caused by particulate matter in the rat and determining the role of long noncoding RNAs MEG3 and HOTAIR.

Increasing air pollution is associated with serious human health problems. P-coumaric acid (PC) is a herbal phenolic compound that exhibits beneficial pharmacological potentials. Here, the protective effect of PC on liver injury induced by air pollution was examined. Thirty-two adult male Wistar rats (200-250 g) were divided randomly into four groups (n = 8). The groups were; Control (rats received DMSO and then exposed to clean air), PC (rats received PC and then exposed to clean air), DMSO + Dust (rats received DMSO and then exposed to dust), and PC + Dust (the animals received PC and then exposed to dust). The clean air, DMSO, PC, and dust were administrated 3 days a week for 6 consecutive weeks. The rats were anesthetized and their blood samples and liver sections were taken to conduct molecular, biomedical, and histopathological tests. Dust exposure increased the liver enzymes, bilirubin, triglyceride, cholesterol, and the production of liver malondialdehyde, and decreased in liver total anti-oxidant capacity and serum high-density lipoprotein. It also increased the mRNA expression of inflammatory-related cytokines, decreased the mRNA expression of SIRT-1, decreased the expression levels of miR-20b5p, and MEG3 while increased the expression levels of miR-34a, and HOTAIR. Dust exposure also increased the liver content of three cytokines TNF-α, NF-κB, HMGB-1, and ATG-7 proteins. PC enhanced liver function against adverse effects of dust through recovering almost all the studied variables. Exposure to dust damaged the liver through induction of oxidative stress, inflammation, and autophagy. PC protected the liver against dust-induced cytotoxicity.

Antibacterial Effects of Nanocomposites on Efflux Pump Expression and Biofilm Production in Pseudomonas aeruginosa: A Systematic Review.

BACKGROUND: Pseudomonas aeruginosa is an opportunistic gram-negative pathogen with multiple mechanisms of resistance to antibiotics. This systematic review aimed to study the antibacterial effects of nanocomposites on efflux pump expression and biofilm production in P. aeruginosa. METHODS: The search was conducted from January 1, 2000, to May 30, 2022, using terms such as (P. aeruginosa) AND (biofilm) AND (antibiofilm activity) AND (anti-Efflux Pump Expression activity) AND (nanoparticles) AND (Efflux Pump Expression) AND (Solid Lipid NPS) AND (Nano Lipid Carriers). Many databases are included in the collection, including ScienceDirect, PubMed, Scopus, Ovid, and Cochrane. RESULTS: A list of selected articles was retrieved by using the relevant keywords. A total of 323 published papers were selected and imported into the Endnote library (version X9). Following the removal of duplicates, 240 were selected for further processing. Based on the titles and abstracts of the articles, 54 irrelevant studies were excluded. Among the remaining 186 articles, 54 were included in the analysis because their full texts were accessible. Ultimately, 74 studies were selected based on inclusion/exclusion criteria. CONCLUSION: Recent studies regarding the impact of NPs on drug resistance in P. aeruginosa found that various nanostructures were developed with different antimicrobial properties. The results of our study suggest that NPs may be a feasible alternative for combating microbial resistance in P. aeruginosa by blocking flux pumps and inhibiting biofilm formation.

Association of the corona virus (Covid-19) epidemic with environmental risk factors.

The current outbreak of the novel coronavirus SARS-CoV-2 (coronavirus disease 2019; previously 2019-nCoV), epicenter in Hubei Province (Wuhan), People's Republic of China, has spread too many other countries. The transmission of the corona virus occurs when people are in the incubation stage and do not have any symptoms. Therefore, the role of environmental factors such as temperature and wind speed becomes very important. The study of Acute Respiratory Syndrome (SARS) indicates that there is a significant relationship between temperature and virus transmission and three important factors, namely temperature, humidity and wind speed, cause SARS transmission. Daily data on the incidence and mortality of Covid-19 disease were collected from World Health Organization (WHO) website and World Meter website (WMW) for several major cities in Iran and the world. Data were collected from February 2020 to September 2021. Meteorological data including temperature, air pressure, wind speed, dew point and air quality index (AQI) index are extracted from the website of the World Meteorological Organization (WMO), The National Aeronautics and Space Administration (NASA) and the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Statistical analysis carried out for significance relationships. The correlation coefficient between the number of infected people in one day and the environmental variables in the countries was different from each other. The relationship between AQI and number of infected was significant in all cities. In Canberra, Madrid and Paris, a significant inverse relationship was observed between the number of infected people in one day and wind speed. There is a significant positive relationship between the number of infected people in a day and the dew point in the cities of Canberra, Wellington and Washington. The relationship between the number of infected people in one day and Pressure was significantly reversed in Madrid and Washington, but positive in Canberra, Brasilia, Paris and Wuhan. There was significant relationship between Dew point and prevalence. Wind speed showed a significant relationship in USA, Madrid and Paris. AQI was strongly associated with the prevalence of covid19. The purpose of this study is to investigate some environmental factors in the transmission of the corona virus.

p-Coumaric acid has pure anti-inflammatory characteristics against hepatopathy caused by ischemia-reperfusion in the liver and dust exposure.

Objectives: Studies show that chronic injuries like air pollution or acute damage such as hepatic ischemia-reperfusion (IR) cause various cellular pathologies such as oxidative stress, apoptosis, autophagy, and inflammation in hepatocytes. p-Coumaric acid (p-CA) is known as an antioxidant with many therapeutic impacts on inflammatory-related pathologies. In this experiment, we aimed to assess the hepatoprotective effects of p-CA on liver damage induced by dust and IR injury in adult male rats. Materials and Methods: Forty-eight adult male Wistar rats were divided into 6 groups; Control (CTRL); sham; DMSO+Dust+Laparotomy (LPT); DMSO+Dust+Ischemia-reperfusion (IR); p-CA+Dust+LPT; and p-CA+Dust+IR. Clean air, DMSO, p-CA, and dust were administrated 3 days a week for 6 consecutive weeks. Animals were sacrificed, the blood samples were aspirated and the liver sections were prepared for biochemical and histopathological assessments. Results: Significantly (P<0.05), the results represented that dust and IR can potentially increase the levels of ALT, AST, direct and total bilirubin, triglyceride, and cholesterol in serum. Also, MDA, TNF-α , NF-κB . HMGB-1 and ATG-7 levels were increased in hepatocytes. Gene expression of Nrf2, HOX-1, IL-6, HOTAIR, and miR-34a showed an incremental trend in the liver tissue. Total antioxidant capacity (TAC) in hepatocytes was decreased following dust exposure and IR induction. Also, miR-20b-5p, MEG3, and SIRT1 in the liver were decreased in dust and dust+IR groups. Conclusion: p-CA alleviated pathological changes caused by dust exposure and IR injury. p-CA protected hepatic injury induced by dust and IR by inhibition of oxidative injury, inflammation, and autophagy.

Preparation of Zinc Oxide Nanoparticles Assisted by Okra Mucilage and Evaluation of its Biological Activities.

BACKGROUND: In this study, zinc oxide nanoparticles (ZnO-NPs) were biologically synthesized from Abelmoschus esculentus L. (Okra) mucilage fraction (OM). METHODS: Analytical techniques were employed to study the formation and properties of OM-ZnO NPs, including their morphology, shape, size distribution, and surface charges. Additionally, OM-ZnO NPs were assessed for their antimicrobial, antioxidant, and cytotoxic properties. RESULTS: UV-visible spectroscopy confirmed the formation of OM-ZnO NPs, evident by the appearance of an SPR peak at 368.8 nm. The FTIR spectroscopy demonstrated that OM functional groups contribute to the formation and stability of the NPs. Micrographs from TEM and SEM showed that OM-ZnO NPs ranged from 15-40 nm in diameter, whereas hydrodynamic diameter and surface charge values obtained from Zeta and DLS were 72.8 nm and 14.6 mv, respectively. XRD analysis indicated the OM-ZnO NPs were crystalline with a wurtzite structure and a crystallite size of 27.3 nm, while EDX revealed a zinc: oxygen ratio of 67.5:34. Further, the OM-ZnO NPs demonstrated significant antimicrobial activity in response to different types of bacteria. In the antioxidant assay, the OM-ZnO NPs scavenged DPPH with 68.6% of the efficiency of ascorbic acid (100%). CONCLUSION: The present study demonstrated the cytotoxic efficacy of MO-ZnO NPs against MCF7 cells with an IC50 of 43.99 µg/ml. Overall, the green synthesis of ZnO NPs by OM was successful for many biological applications, such as antimicrobial, antioxidant, and anticancer. Moreover, OM-ZnO NPs can be applied as a biologically-derived nanotherapeutic agent.

The Impact of Metformin on Dust-Induced Histopathological Changes and Oxidative Stress in the Liver: An Insight into Dust Concentration and Liver Biomarkers in Animal Models.

Background: Environmental pollution has a profound impact on both human and animal life. Khuzestan province, which has been plagued by intense dust storms and pollution for decades, is the focus of this study. The research aims to investigate the protective effects of metformin against the toxicity of particulate matter in the livers of rats. Methods: Male Wistar rats were selected for the study and divided into six groups: a control group, Metformin-treated groups, Iraqi dust-exposed group (Iraqi-D), Local dust-exposed group (Local-D), Iraqi dust-exposed with Metformin treatment group (Iraqi-D+Metformin), and Local dust-exposed with Metformin treatment group (Local-D+Metformin). The rats were exposed to local and Iraqi dust through a nebulizer and received oral metformin for a duration of 21 days. At the end of the intervention, liver biomarkers and oxidative stress factors were evaluated enzymatically. Results: The study revealed that rats exposed to Iraqi and local dust experienced a significant increase in liver biomarkers, including aspartate aminotransferase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALK) levels, alongside a decrease in glutathione (GSH) concentrations and an increase in malondialdehyde (MDA) levels. However, treatment with metformin was effective in preventing the increase in these biomarkers, restoring GSH levels, and averting the rise in MDA levels, as compared to the control group. Conclusions: Exposure to particulate matter from Iraq and the local region can induce alterations in biomarkers and oxidative stress levels in the rat liver, and these effects can be mitigated through metformin treatment.

Estimation of the effects PM2.5, NO2, O3 pollutants on the health of Shahrekord residents based on AirQ+ software during (2012-2018).

Research objectives: Intertwined with modern life, air pollution is not a new phenomenon. Air pollution imposes a significant number of deaths and disease complications on society, and therefore it is very important to determine the extent of its effects on health in any society. This study sought to evaluate the concentration and short-term and long-term excess mortality attributed to PM2.5, NO2 and O3 observed in Shahrekord. Procedure: Hourly concentrations of PM2.5, O3, and NO2 measured at different stations of the Shahrekord Monitoring Network were obtained from the Shahrekord Department of Environment (DOE). Then, for different air quality monitoring stations, the average 24-hour PM2.5 concentration, the one-hour average NO2 concentration and the maximum 8-hour daily O3 concentration were calculated using Excel 2010. When the maximum 8-hour daily ozone level exceeds 35, it drops below 35 to calculate the SOMO35 index for modeling. Results: The death rates of IHD, COPD, lung cancer and ALRI and stroke related to PM2.5 were 176, 7, 0, 10, 105, respectively. The effect of ozone on respiratory mortality was zero. During the study period in Shahrekord, no respiratory mortality was determined due to ozone and acute lower respiratory tract infection (ALRI). this study is first ever study on health effects of air pollution in shahrekord city. Conclusion: A significant number of deaths due to air pollutants in Shahrekord have been reported. It can be concluded that by designing and implementing strategies and measures to control air pollution, both health effects and economic losses are prevented.

Protective effect of crocin on hemodynamic parameters, electrocardiogram parameters, and oxidative stress in isolated hearts of rats exposed to PM10.

Objectives: Exposures to particulate matter (PM) have been related to increased risk for cardiovascular health effects and can promote cardiac ischemia and oxidative stress. Crocin has strong antioxidant properties and stress-reducing effects. Therefore, this study considered the effect of crocin on cardiovascular parameters in rats exposed to PM10. Materials and Methods: Forty Wistar rats (male, 250-300 g) were grouped as control, receiving normal saline and crocin, receiving PM10, receiving PM10+Crocin. Instillation of PM10 into the trachea was done. Forty-eight hours after exposure to the normal saline or PM, the heart was separated. Hemodynamic and electrophysiological factors were measured. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase activity (CAT), malondialdehyde (MDA), xanthine oxidase, were evaluated by kits. Results: The voltage of the QRS complex was significantly reduced and PR and QTc intervals increased in PM10 groups. Hemodynamic parameters before ischemia and in the ischemic-reperfusion stage, in the PM10 group, showed a significant decrease. In the ischemic hearts of the PM10 group, a significant decline in the activity of CAT, SOD, and GPx, and a significant increase in MDA and XOX enzymes activity were observed, and crocin improved all of these factors. Conclusion: Cardiac ischemia causes abnormal hemodynamic factors of the heart, which are exacerbated by PM10 and further reduce the heart's contractile strength. Increased oxidative stress due to PM10 is probably one of the important reasons for these changes. This study suggests that the use of antioxidants such as crocin improves the cardiovascular adverse effects of myocardial ischemia and PM10 exposure.

The impact of meteorological parameters on PM10 and visibility during the Middle Eastern dust storms.

Air pollution is one of the most pressing issues in populated Middle Eastern cities, in particular for the city of Ahvaz, Iran, imposing deleterious effects on the environment, public health, economy, culture, and other sectors. In this study, we investigate the relationship between meteorological parameters, PM10, AOD, air mass source origin, and visibility during severe desert dust storms (Average3h PM10 > 3200 µg m-3) between 2009 and 2012. Six of seven such events occurred between February and March. Interestingly, for the seven cases there was always an alarming PM10 mass concentration peak (137-553 µg m-3) between 12:00-18:00 (local time) that was 18-24 h before the dominant peak of the storm (3279-4899 µg m-3). The maximum wind speed over the multi-day periods examined for the dust storms is usually observed 6 h before the alarming PM10 peak. The minimum relative humidity, dew point temperature and air pressure occurred ± 3 h around the time of the alarming PM10 peak. Wind speed was the meteorological parameter that was consistently higher around the time of the first peak as compared to the second peak, with the reverse being true for sea level pressure. Based on four years of daily data in Ahvaz, PM10 was positively correlated with wind speed and air temperature and inversely correlated with sea level pressure and RH. An empirically-derived equation with R2 = 0.95 is reported to estimate the maximum PM10 concentration for severe desert dust events in the study region based on meteorological parameters. Finally, AOD is shown to correlate strongly (R2 = 0.86) with PM10 during periods with severe desert dust storms in the region.

Prediction of airborne pollen concentrations by artificial neural network and their relationship with meteorological parameters and air pollutants.

After the early rainfall in the autumn of 2013, respiratory syndromes spread in the Khuzestan province of Iran with the most severity in Ahvaz. There have been recurring outbreaks in recent years. Considering that pollen-derived airborne allergens are regarded as key aeroallergens and the main cause of allergic rhinitis and asthma, this work aimed to forecast total pollen concentration in Ahvaz through an artificial neural network (ANN), followed by evaluating the pollen spatial distribution across the city and the association between pollen concentrations and environmental parameters. The utilized ANN in this work included an input layer with 13 parameters, a hidden layer of five neurons, and an output layer. Data were classified into training, validation, and testing sets. The ANN was implemented with 70% and 80% of data for training. The value of the correlation coefficient for the data validation of these two networks was 0.89 and 0.92, respectively. The results also indicated that despite the difference in the mean concentration of the pollens in various areas of Ahvaz, this difference was not statistically significant (P > 0.05). Furthermore, there was a negative correlation between the concentration of total pollen and relative humidity, precipitation, and air pressure. However, it had a positive correlation with temperature. Consequently, considering the logistical challenges of monitoring bioaerosols in the air, the ANN approach could predict total pollen concentrations. Therefore, in addition to measurements, the ANN technique can be a good tool to enable authorities to mitigate the impact of airborne pollen on people.

Temporal profiles of ambient air pollutants and associated health outcomes in two polluted cities of the Middle East.

Dust storms and particulate matters had been increased due to climate change in the Middle East. On the other hand, urbanization and industrialization raised levels of gaseous air pollutants in all big cities. In the current study, air pollution information collected from Environmental Protection Agency of Khuzestan and Tehran containing hourly O3, NO2, CO, SO2, PM10 and PM2.5 concentrations between 2014 and 2015. This study evaluated the air quality of these two cities by Air Quality Index (AQI). As a result, mean concentrations of O3, NO2, PM10 and PM2.5 were higher in Ahvaz than Tehran while Tehran was more pollutant in terms of CO and SO2. Diurnal variations of O3 in weekend were the only trend located above weekday variations along the daytimes. Hourly variations of all pollutants changed with a wider range of concentrations in Ahvaz. Diurnal peaks of all pollutants showed their highest level on Monday as the busiest day in mega city, Tehran with the exception of SO2. PM2.5 was the worst and limiting pollutant for both cities. Accordingly, winter was the most polluted season by 77 and 33 µg m-3 in Ahvaz and Tehran, respectively. Number of clean days was significantly lower in Ahvaz (no-day) than mega city, Tehran (<17 days). The number of unhealthy days was also presented significantly higher in Ahvaz (>186 days). Although, annual PM2.5 concentrations were more in Ahvaz, the higher at-risk population in Tehran caused more health endpoints in the capital of Iran. Consequently, both cities should have their own especial pattern to control air pollution and attributed health damages.