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The particulate matter has become a serious health problem in some large cities in the world. These particles are a complex mixture of chemical compounds which change based on location and time and, consequently, can cause different health-related effects. The exact mechanism of the effect of these particles is not yet known for certain. However, it seems that numerous mechanisms through the production of ROS and, eventually, DNA destruction, which are related to a wide range of diseases, are among the causes of particles' health-related effects. The present study is aimed to evaluate and compare the genotoxicity potential of particles collected in Tehran, Iran, in urban and rural regions during spring and autumn as well as dusty and inversion conditions. These effects were examined using the comet assay on human pulmonary epithelial cells (A549). Results showed that all the particles had the potential for genotoxicity at the concentration used in this study (75,150 and 300 μg/ml). Moreover, DNA destruction changed with season, site, and even dusty and inversion atmospheric conditions. These changes mostly belonged to urban particles. In general, urban particles in autumn and, specifically, on days with inversion had higher genotoxicity (p < 0.01). Difference was observed between dusty and regular days so that regular days were more potent (p < 0.05). A strong correlation was observed between the effects of most PAH compounds and other metals such as Cr, Co, Cd, Mn, As, and also SO 4 , which were mostly the result of combustion in vehicle engines in urban regions. No difference was observed for rural particles at different conditions and seasons.

The original version of this article unfortunately contained a mistake. Figure 6 caption should be "The light microscopic image (a) and transmission electron microscopic image (b) of A549 cell after 24 h of exposure to PM10 (150 μg/ml).

Novel graphene oxide (GO)-based adsorbent embedded with epichlorohydrin (ECH) as a coupling agent and dimethylamine (DMA) as a ligand (GO-ECH-DMA) were prepared and employed for endotoxin removal from aqueous solutions. The physicochemical properties of nanocomposite were fully characterized. The model attributed to batch adsorption process was optimized employing response surface methodology (RSM) via various parameters such as pH, GO-ECH-DMA dosage, and contact time and endotoxin concentration. The p-value with low probability (<0.00001), determination coefficient (R 2 =0.99) and the non-significant lack of fit (p > 0.05) showed a quadratic model with a good fit with experimental terms. The synergistic effects of the linear term of contact time and GO-ECH-DMA dosage on endotoxin removal were significant. The optimum condition for endotoxin removal was obtained at pH of 5.52, GO-ECH-DMA dosage of 21 mgL -1 , contact time of 56 min and endotoxin concentration of 51.3 endotoxin units per milliliter (EUmL -1 ). The equilibrium was the better explained by Langmuir isotherm with the maximum monolayer adsorption capacity of 121.47 EUmg-1, while the kinetics of the endotoxin adsorption process was followed by the pseudo-second-order model. The adsorbent could be recycled with NaOH. The possible mechanisms of endotoxin adsorption were proposed by hydrogen-bonding, π-π stacking, and electrostatic interaction., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Air pollution and dust storms are associated with increased cardiovascular hospital admissions. The aim of this study was to investigate the association between short-term exposure to ambient air pollutants and CVD (cardiovascular disease) events in a long-term observational period. The study included the events of cardiovascular diseases (namely coronary artery disease, ischemic heart disease, myocardial infarction, and pneumo thrombo embolism) within the population of Shiraz, from March 21, 2009 to March 20, 2015. Also, each patient's demographics were recorded. Main meteorological variables and five ambient pollutants (CO, O 3 , SO 2 , NO 2 , and PM 10 ) were recorded. Statistical analysis was performed using linear regression (GLM) and a generalized additive model (GAM) estimating Poisson distribution and adjusted for the main risk factors and ambient meteorological variables. A mild prevalence (51.5%) of coronary artery disease (CAD) was registered in 6425 events. In GLM analysis, we observed an association among the pollutants with the coronary artery disease hospital admissions which was in the order of CO, NO 2 , and PM 10 . The highest association of each pollutant with hospital admission was observed as PM 10 at lag 4 (RR = 1.08; 95% CI 1.02, 1.14 and p < 0.05), NO 2 at lag 0 (RR = 1.22; 95% CI 1.00, 1.48), and CO at lag 0 (RR = 1.52 95% CI = (1.16, 1.99)). However, on dusty days, there were significantly higher numbers of referrals of cardiovascular patients (mean = 7.54 ± 4.44 and p = 0.002,) than on non-dusty days. According to these data, dust storms and some types of pollutants in the air are responsible for more admissions to hospitals for cardiovascular problems.

Purpose: This study aimed to investigate chemical composition of PM 10 (particulate matter with aerodynamic diameter ≤ 10 μm) during dust storm and inversion in Tehran and hemolysis effects., Methods: PM 10 was sampled in Tehran, Iran, during dust storm and inversion conditions. Water soluble ions (F¯, Cl¯, NO 2 ¯, NO 3 ¯, SO 4 ¯ 2 , Na + , K + , NH 4 + , Ca +2 , Mg +2 ) and elements (Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Se, Sn, Sr, V, Zn, Pt, Rh, Pd, As and Si) were analyzed by ion chromatograph (IC) and inductively coupled plasma optical emission spectrometer (ICP-OES), respectively. Hemolysis was examined as in vitro at PM 10 concentrations of 50-300 μg/ml., Results: Daily average of PM 10 concentrations in dusty and inversion days were 348.40 and 220.54 μg/m 3 , respectively. Most prevalence ionic components were NO 3 ¯, Cl¯, SO 4 ¯ 2 and Ca +2 during dust storm and SO 4 ¯ 2 , NO 3 ¯, Cl¯ and NH 4 + during inversion. Si, Fe and Al had the maximum values in both conditions. Particles associated with both conditions induced hemolytic responses. PM 10 from dusty day showed a higher hemolysis percent (10.24 ± 4.67%) than inversion (9.08 ± 5.47%), but this difference was not significant ( p  = 0.32). Hemolytic effects were significantly intensified by increased PM concentrations ( p  < 0.001) in a dose-response manner., Conclusions: As the results, chemical composition of sampled particles from inversion days and dust storm was different from each other. Hemolytic effects of particles during dust storm were more than inversion days. However, this difference was not statistically significant., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest.

Purpose: The aim of this study is evaluation of the perchloroethylene degradation from aqueous solutions by non-thermal plasma produced in dielectric barrier discharge reactor in two different scenarios: first plasma generated with 225 cc/min mixture of oxygen and argon flow (12% gas ratio of O 2 /Ar), and in the second scenario plasma generated with 225 cc/min of pure argon gas., Methods: Design studies were performed using response surface methodology and central composite design. All experiments with the selected levels of independent parameters including the initial concentration of perchloroethylene (5-100 mg/L), voltage (20-5 kv) and contact time (15-180 s) was implemented, and 29 tests were proposed by using response surface methodology and central composite design was performed in two experimental scenarios., Results: Results showed that the Pseudo first-order kinetics coefficient of perchloroethylene degradation in the mixture of oxygen and argon and pure argon scenario under the optimum conditions were 0.024 and 0.016 S -1 respectively. Results conveyed that in order to achieve the highest removal efficiency (100%), the values of contact time, perchloroethylene concentration and voltage variables were predicted 169.55 s, 74.3 mg/l, 18.86 kv respectively in mixture of oxygen and argon scenario and also were predicted 203 s, 85.22 mg/l, 20.39 kv respectively in pure argon scenario., Conclusions: In the recent study dielectric barrier discharge was an efficient method for perchloroethylene removal with both oxygen an argon mixture and pure argon as input gas. Both input voltage and reaction time has positive effect on perchloroethylene removal; but initial perchloroethylene concentration has negative effect on perchloroethylene removal. Comparison of two plasma scenarios with different input gas shown that plasma generated by mixture of oxygen and argon gas was more powerful and had higher removal efficiency and degradation kinetics than the plasma generated by pure argon gas., Competing Interests: Compliance with ethical standardsThere are no conflicts of interest in this manuscript.

The relationship between apparent temperature and cardiovascular disease (CVD) mortality was studied in Rasht, Iran, from 2005 to 2014. The effects of apparent temperature on CVD mortality were investigated using the distributed lag nonlinear model. Data on all types of cardiovascular mortality cases according to the International Classification of Diseases were collected from the only cardiovascular hospital in Rasht, and the meteorological variables were obtained from Rasht Meteorological Center during the period of study. Our findings showed that low temperatures had significant impacts on CVD mortality, and a reverse J-shaped temperature-mortality relationship was found. Moreover, immediate effects of hot temperatures on CVD mortality with the strongest effects on the same day but delayed effects of cold temperature was observed. This study showed that exposure to both hot and cold apparent temperatures was associated with increased cardiovascular mortality in Rasht.

In this research, probable arsenic contamination in drinking water in the city of Ardabil was studied in 163 samples during four seasons. In each season, sampling was carried out randomly in the study area. Results were analyzed statistically applying SPSS 19 software, and the data was also modeled by Arc GIS 10.1 software. The maximum permissible arsenic concentration in drinking water defined by the World Health Organization and Iranian national standard is 10 μg/L. Statistical analysis showed 75, 88, 47, and 69% of samples in autumn, winter, spring, and summer, respectively, had concentrations higher than the national standard. The mean concentrations of arsenic in autumn, winter, spring, and summer were 19.89, 15.9, 10.87, and 14.6 μg/L, respectively, and the overall average in all samples through the year was 15.32 μg/L. Although GIS outputs indicated that the concentration distribution profiles changed in four consecutive seasons, variance analysis of the results showed that statistically there is no significant difference in arsenic levels in four seasons.

There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in groundwater resources of Larestan and Gerash regions in Iran were analyzed from 2003 to 2010 using a geospatial information system and the Mann-Kendall trend test. The mean concentrations of fluoride for the 8-year period in the eight cities and 31 villages were 1.6 and 2.0 mg/l, respectively; the maximum values were 2.4 and 3.8 mg/l, respectively. Spatial, temporal, and spatiotemporal variability of fluoride in overall groundwater resources were relatively constant over the years. However, results of the Mann-Kendall trend test revealed a monotonic trend in the time series of one city and 11 villages for the 8-year period. Specifically, one city and three villages showed positive significant Kendall's Tau values, suggesting an upward trend in fluoride concentrations over the 8-year period. In contrast, seven villages displayed negative significant Kendall's Tau values, arguing for a downward trend in fluoride concentrations over the years. From 2003 to 2010, approximately 52 % of the Larestan and Gerash areas have had fluoride concentrations above the maximum permissible Iranian drinking water standard fluoride level (1.4 mg/l), and about 116,000 people were exposed to such excess amounts. Therefore, our study supports for a close monitoring of fluoride concentrations from health authorities in monthly intervals, especially in villages and cities that showed positive trend in fluoride concentrations. Moreover, we recommend simultaneous implementation of cost-effective protective measures or interventions until a standard fluoride level is achieved.

Objective: Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most common behavioral ‎disorders in children effecting the families and society. This systematic review examined ‎the literature on the role of lead exposure in children with ADHD‏ ‏symptoms. Articles were ‎analytically compared, focusing on the methodology used to assess exposure and‏ ‏adverse ‎effects‏ ‏on children with ADHD. ‎, Method: Using the search strategy from six databases (Pub Med, PsycINFO, Web of Science, SID, ‎IRAN Medex, IRAN DOC), hand searching in key journals, list of references of selected ‎articles and gray literature, without time and language limitation, articles up to May 2014 ‎were entered into this review. In this review, 1,387 articles were acquired at the primary ‎search. Study selection and quality assessment processes were done based on Cochrane ‎library guidelines. After assessing the quality and inclusion and exclusion criteria, 18 articles ‎were selected and entered into the data synthesis.‎, Results: Blood Lead level (BLL) of less than 10µg/dL in children has been attributed to at least one ‎type of ADHD i.e., Combined / Inattentive / Hyperactive-Impulsive. The results of this ‎study revealed that in 16 out of the 18 studies, a significant association was found between ‎BLL and one of the types of ADHD.‎, Conclusion: Based on the findings of this study, even the BLL of less than the action level of 10µg/dL, ‎chosen by Centers for Disease Control and Prevention (CDC), may affect children with ‎ADHD.‎.

Background: Anaerobic treatment methods are more suitable for the treatment of concentrated wastewater streams, offer lower operating costs, the production of usable biogas product. The aim of this study was to investigate the performance of an Anaerobic Fluidized Bed Reactor (AFBR)-Aerobic Moving Bed Bio Reactor (MBBR) in series arrangement to treat Currant wastewater., Methods: The bed materials of AFBR were cylindrical particles made of PVC with a diameter of 2-2.3 mm, particle density of 1250 kg/m(3). The volume of all bed materials was 1.7 liter which expanded to 2.46 liters in fluidized situation. In MBBR, support media was composed of 1.5 liters Bee-Cell 2000 having porosity of 87% and specific surface area of 650m(2)/m(3)., Results: When system operated at 35 ºC, chemical oxygen demand (COD) removal efficiencies were achieved to 98% and 81.6% for organic loading rates (OLR) of 9.4 and 24.2 g COD/l.d, and hydraulic retention times (HRT) of 48 and 18 h, in average COD concentration feeding of 18.4 g/l, respectively., Conclusion: The contribution of AFBR in total COD removal efficiency at an organic loading rate (OLR) of 9.4 g COD/l.d was 95%, and gradually decreased to 76.5% in OLR of 24.2 g COD/l.d. Also with increasing in organic loading rate the contribution of aerobic reactor in removing COD gradually decreased. In this system, the anaerobic reactor played the most important role in the removal of COD, and the aerobic MBBR was actually needed to polish the anaerobic treated wastewater.

Potential of wastewater treatment in car industry and groundwater contamination by volatile organic compounds include perchloroethylene (PCE), trichloroethylene (TCE) and dichloromethane (DCM) near car industry was conducted in this study. Samples were collected in September through December 2011 from automobile industry. Head-space Gas chromatography with FID detector is used for analysis. Mean PCE levels in groundwater ranged from 0 to 63.56 μg L(-1) with maximum level of 89.1 μg L(-1). Mean TCE from 0 to 76.63 μg L(-1) with maximum level of 112 μg L(-1). Due to the data obtained from pre treatment of car staining site and conventional wastewater treatment in car factory, the most of TCE, PCE and DCM removed by pre aeration. Therefor this materials entry from liquid phase to air phase and by precipitation leak out to the groundwater. As a consequence these pollutants have a many negative health effect on the workers by air and groundwater.

Levels of tributyltin (TBT) and its degradation products, mono (MBT) and dibutyltin (DBT), were monitored in fish commonly consumed in Iran. Samples were purchased from fish markets at seasonal intervals in 2010 along the North coast of Iran. Concentration of MBT, DBT and TBT in the muscle of these fish were in the range of n.d. -1.01 ± 0.84, n.d. -0.33 ± 0.26 and n.d. -4.31 ± 0.95 ngg(-1) (wet weight), respectively. Residue levels of butyltins were found lower than the tolerable average residue level of 100 ngg(-1) (wet weight).

The aim of this study was estimation of PCDD/PCDFs emissions from various sources in Iran. The results indicated total PCDD/PCDFs emissions in Iran in 2010, was 1,957 g TEQ. Of this amount, about 705.8, 0.5, 463.5, 144.1 and 643.2 g TEQ/year was released to air, water, land, products, and in residues, respectively. Open burning processes and metal production are the major contributors to be known environmental sources of PCDD/PCDFs that contribute to about 70% of total PCDD/PCDFs emissions in Iran. The results showed that total PCDD/PCDFs emissions in Iran per inhabitant were about 26.5 g TEQ/million that is high relatively.

The present study aimed to evaluate the performance of a continuous bipolar ECEO-EF reactor designed for simultaneous removal of ammonia and phosphate from wastewater effluent. The reactor was comprised of two distinct units: electrochemical and separation. In the electrochemical unit, Al, stainless steel, and RuO(2)/Ti plates were used. All the measurements were performed according to the standard methods. Maximum efficiency of the reactor for phosphate removal was 99% at pH of 6, current density of 3A, detention time of 60 min, and influent phosphate concentration of 50mg/l. The corresponding value for ammonia removal was 99% at a pH of 7 under the same operational conditions as for phosphate removal. For both phosphate and ammonia, the removal efficiency was highest at neutral pH, with higher current densities, and with lower influent concentrations. In addition to removal of phosphate and ammonia, application of the Al(3+) plates enabled the removal of nitrite and nitrate, which may be present in wastewater effluent and are also products of the electrochemical process. The reactor was also able to decrease the concentrations of phosphate, ammonia, and COD under actual wastewater conditions by 98%, 98%, and 72%, respectively. According to the results of the present study, the reactor can be used for efficient removal of ammonia and phosphate from wastewater., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Potential of groundwater contamination by trichloroethylene (TCE) and other volatile organic compounds VOCs near car industry was conducted in this study. TCE, PCE, toluene, xylene, dichloromethane, cyclohexane, n-hexane and n-pentane were detected in all groundwaters. Mean TCE levels in groundwater ranged from 124.37 to 1,035.9 μg L⁻¹ with maximum level of 1,345.7 μg L⁻¹. Due to the data obtained from conventional wastewater treatment in car factory the TCE removal efficiency was only 24 percent which necessitates the TCE removal by advanced treatment processes before the use of well water.

Fluoride concentration in groundwater resources that used as the source of drinking water in urban areas of Iran was determined. All of the groundwater wells located in urban areas were monitored in 2008. Fluoride concentration of water samples was measured using SPADNS method. The nationwide mean fluoride concentration in the groundwater resources was found to be 0.47 +/- 0.28 (+/- standard deviation) mg/L. Only in Bushehr Province, the provincial mean fluoride level in the groundwater resources was higher than the WHO guideline value of 1.5 mg/L (1.86 +/- 0.86 mg/L). At nationwide level, the portion of extracted groundwater with fluoride concentration lower than the minimum permissible level of 0.5 mg/L, desirable fluoride range of 0.5-1.5 mg/L and elevated fluoride level was 69.2, 29.3 and 1.4%, respectively. In the areas with low fluoride content drinking water, it is recommended that fluoride is absorbed by use of high fluoride content foods and beverages. The recommendations for the circumstances with excessive fluoride content of drinking water are provision of drinking water from alternative sources and defluoridation of drinking water by point-of-use systems, respectively.

A large amount of chemicals is annually applied at the agricultural soils as fertilizers and pesticides. Such applications may result in the increase of heavy metals particularly Cd, Pb, and As. The objective of this study was to investigate the variability of chemical applications on Cd, Pb, and As concentrations of wheat-cultivated soils. Consequently, a study area was designed and was divided into four subareas (A, B, C, and D). The soil sampling was carried out in 40 points of cultivated durum wheat during the 2006-2007 periods. The samples were taken to the laboratory to measure their heavy metal concentration, soil texture, pH, electrical conductivity, cationic exchange capacity, organic matter, and carbonate contents. The result indicated that Cd, Pb, and As concentrations were increased in the cultivated soils due to fertilizer application. Although the statistical analysis indicates that these heavy metals increased significantly (P value<0.05), the lead and arsenic concentrations were increased dramatically compared to Cd concentration. This can be related to overapplication of fertilizers as well as the pesticides that are used to replant plant pests, herbs, and rats.

The waste management practices in primary healthcare centres of Iran were investigated in the present study. A total of 120 primary healthcare centres located across the country were selected using the cluster sampling method and the current situation of healthcare waste management was determined through field investigation. The quantities of solid waste and wastewater generation per outpatient were found to be 60 g outpatient(-1) day(-1) and 26 L outpatient(-1) day(-1), respectively. In all of the facilities, sharp objects were separated almost completely, but separation of other types of hazardous healthcare solid waste was only done in 25% of the centres. The separated hazardous solid waste materials were treated by incineration, temporary incineration and open burning methods in 32.5, 8.3 and 42.5% of the healthcare centres, respectively. In 16.7% of the centres the hazardous solid wastes were disposed of without any treatment. These results indicate that the management of waste materials in primary healthcare centres in Iran faced some problems. Staff training and awareness, separation of healthcare solid waste, establishment of the autoclave method for healthcare solid waste treatment and construction of septic tanks and disinfection units in the centres that were without access to a sewer system are the major measures that are suggested for improvement of the waste management practices.

Development of an acclimatized SOB biofilm, startup and performance of a fixed bed bioscrubber packed with corrugated tube parts as a media having high specific surface area was investigated. Bioscrubber was a cylindrical Plexiglas air-and water-tight column with 10 L in working bed volume. Sludge from a tannery wastewater treatment plant was used as a seed for SOB separation, acclimation and enrichment. Enriched acclimatized SOB were applied as inoculum for biofilm development, which was carried out by recirculating the prepared microbial suspension through the bed. Thickness of the developed biofilm was 56 microm in which active acidophilic autotrophic H2S oxidizing bacteria were completely predominated. Activity measurements showed highest biodegradation rate of biofilm at liquid pH around 3. Due to employing an efficient specialized biofilm, startup period of the reactor was quite short and H2S removal efficiency just 12 h after starting up reached above of 92% and increased to 96% at day 3 of starting up while inlet H2S concentration gradually was increased to around 30 ppm. At the end of start up pH of the recycle liquid was modified to the optimal value of 3 +/- 0.5 in which biofilm demonstrated the highest activity in terms of OUR after which removal efficiency increased around 3% while other operating conditions were consistent. Furthermore, performance of the bioscrubber was evaluated at various inlet H2S concentrations ranging from 30 to 150 ppm(v). It was indicated that the inlet H2S concentrations in studied range did not affect the performance of the bioscrubber so that the removal efficiency of H2S was greater than 99.4% at all concentrations. These observations suggested that the development of an efficient specialized SOB biofilm on a media with high specific surface area will decrease the startup course and achieve high removal efficiency in the bioscrubber treating H2S. In addition, operation in acidic recycle liquid will overcome use of alkaline to adjust the pH, which reduce the operation cost of the control system.