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Background: Nowadays, increasing the use of pesticides to manage the agriculture production resulted in increased pesticide residues in final products and concerns about environmental pollution and prevalence of emerging diseases. This study aims to investigate the residual amount of Phosalone toxin in the early and late varieties of peach orchards in Saman city located in Chaharmahal and Bakhtiari province. Methods: In this study, 60 samples of early and late peach varieties of peach orchards were selected randomly. Phosalone residues in early and late peach varieties before and after washing, and after peeling were extracted by QUECHERS method and the amount of extracted toxin were measured by high-performance liquid chromatography (HPLC). The data were analyzed using SPSS v.24 software. Results: Phosalone residues in early peach varieties before and after washing were 3.55 ± 0.94 and 0.31 ± 0.29 mg/kg, respectively. The concentration of Phosalone residues in unwashed early and late peach varieties before washing was 3.17 ± 0.97 mg/kg but decreased to 0.64 ±0.74 mg /kg after washing. Peeling reduced 97.79% of the Phosalone residues in late peach. Early and late peaches covered by the plant pathology clinic and unwashed late peaches not covered by plant pathology clinic were significantly (P < 0.05) higher than the Iranian national standard (2 mg/kg). Conclusion: Washing and peeling the peach significantly decreased the toxin residues. In order to minimize the risk of exposure to Phosalone residues, integrated pest control management programs are essential.

Background: Naphthol, one of the naphthalene derivatives, is the most significant industrial chemical. It is widely used in the biochemical processes, production of dyes, and pharmaceutical industries.Methods: In the present study, N, S-doped TiO2 thin film immobilized on Silica Sulfuric Acid (SSA) glass Microspheres (MS) was investigated as a novel high efficient photocatalyst. We fabricated N, S-doped TiO2 immobilized on SSA using a simple modified sol-gel process. Its photocatalytic activities were then assessed by 1-naphthol solution in the presence of visible light. The physicochemical properties of photocatalyst were characterized using Energy-Dispersive X-ray (EDX), Scanning Electron Microscope (SEM) images, and X-Ray Diffraction (XRD) pattern.Results: According to the obtained results, the optimal pH, time, concentration, and removal efficiency of 1-naphthol for N, S-doped TiO2 /SSA were 5, 50 min, 25 mg/L, and 92.12%.Conclusion: The present study confirms the usability of the immobilized N, S-doped TiO2 on SSA glass MS as a novel, effective, and efficient technique for treating wastewater containing 1-naphthol under visible light.

Backgroundand Aim. Natural organic matter (NOM) has become one of the most serious environmental problems due to its persistence in aqueous solutions and the risk of carcinogenesis. In this study, the removal efficiencies of real and synthetic humic acid (HA) by multi-walled carbon nanotubes (MWCNTs) coated with iron oxide were evaluated. Materials and Methods. The MWCNs were synthesized and coated with iron oxide. In addition, the effects of pH, contact time, mixing speed, and adsorbent dose on the removal efficiency of NOM by MWCNTs-Fe3O4 were studied. Then, the removal efficiency of NOM from real samples was investigated at optimal conditions. The MWCNT-Fe3O4 was characterized by scanning electron microscopy (SEM) test and X-ray diffraction (XRD), respectively. Data analysis was performed using Minitab software based on the Taguchi method. Results. The results showed that MWCNTs were coated with Fe3O4. The SEM test shows particle (MWCNTs-Fe3O4) size in the range of 48–143 nm, and the particles have uniform spherical shapes. Enix software was used to identify the phase in this sample. The conditions including pH=3, mixing speed = 120 rpm, adsorbent dosage = 1.5 g·L−1, and contact time = 90 minutes were selected as optimal for NOM adsorption. The mean removal efficiencies of NOM in synthetic samples at 5, 10, and 20 mg·L−1 concentrations were 86.6%, 84.87%, and 95.41%, respectively. In addition, the mean removal efficiency of NOM in Choghakhor Wetland was 77%. Conclusion. Our findings demonstrated that the MWCNTs-Fe3O4 can be potentially used as an adsorbent for removing natural organic matter (HA) from aqueous solutions.

Abstract Background Critical inter-provincial differences within Iran in the pattern of non-communicable diseases (NCDs) and difficulties inherent to identifying prevention methods to reduce mortality from NCDs have challenged the implementation of the provincial health system plan. The Shahrekord Cohort Study (SCS) was designed to address these gaps in Chaharmahal and Bakhtiari, a province of high altitude in the southwest of Iran, characterized by its large Bakhtiari population, along with Fars and Turk ethnicity groups. Methods This ongoing cohort, a prospective, large-scale longitudinal study, includes a unique, rich biobank and was conducted for the first time in Chaharmahal and Bakhtiari Province in Iran. SCS is a part of the PERSIAN (Prospective Epidemiological Research Studies in IrAN) cohort. The study began in 2015, recruited 10075 participants (52.8% female, 47.2% male) from both urban (n=7034) and rural (n=3041) areas, and participants will be annually followed up for at least 15 years. A cross-sectional analysis was conducted using baseline data from the SCS, using descriptive statistics and logistic regression. Data analysis was performed using Stata software. Results The prevalence of NCDs was 9.8% for type 2 diabetes, 17.1% for hypertension, 11.6% for thyroid disease, 0.2% for multiple sclerosis and 5.7, 0.9 and 1.3% for ischemic heart disease, stroke and myocardial infarction, respectively. The prevalence of multimorbidity (≥2 NCDs) was higher in women (39.1%) than men (24.9%). The means (standard deviations) of age, BMI, systolic blood pressure and fasting blood glucose were 49.5 (9) years, 27.6 (4.6) kg/m2, 115.4 (17.3) mmHg and 96.7 (27.3) mg/dL, respectively. Logistic regression models showed that older age, female gender, living in an urban area, non-native ethnicity, high wealth index, unemployment, obesity, low physical activity, hypertriglyceridemia, high fasting blood sugar, alkaline urine pH and high systolic and diastolic blood pressure were associated with increased prevalence of NCDs. Conclusions The SCS provides a platform for epidemiological studies that will be useful to better control NCDs in the southwest of Iran and to foster research collaboration. The SCS will be an essential resource for identifying NCD risk factors in this region and designing relevant public health interventions.

Introduction: Heavy metals are among the most stable and non-degradable biological pollutants in the environment that can enter the water, soil, air, and therefore, the food chain. In recent years, biological methods, especially with the help of bacteria, have been used to remove heavy metals from industrial waste. The purpose of this study was to identify nickel-resistant (Ni) bacteria in the chemical refinery of Mobarakeh Steel Complex in Isfahan, Iran. Materials & Methods: Samples of wastewater and sludge were evaluated regarding bacterial species and Ni (II)-resistance after dilution and transfer on the culture medium. Ni-resistant strain (II) and Micrococcus luteus SEHD031RS strains were selected for morphological and biochemical tests as well as Ni (II) removal, respectively. Findings: This study showed that five strains had high Ni (II) resistance. Moreover, Micrococcus luteus SEHD031RS and Paenibacillus lautus SEHD031MRA strains showed the highest resistance to Ni (II) with growth at the concentrations of 110 and 90 mg/l, respectively. In this study, the highest nickel (II) removal rate was at pH 6 with a yield of 75.39% and the lowest nickel (II) removal rate was at pH 2 with a yield of 3.22% for Micrococcus luteus SEHD031RS strain. Ethics code: ir.skums. irac.1396-37 Discussion & Conclusions: It can be concluded that the detected strains can be suitable choices for Ni (II) removal from industrial wastewaters according to the features mentioned in this study.

Nowadays, advanced oxidation processes, particularly photocatalyst process and catalytic ozonation by ZnO nanoparticles, are the most efficient method of eliminating pharmaceuticals. The purpose of this study was to compare the efficiency of ultraviolet/zinc oxide (UV/ZnO) and ozone/zinc oxide (O3/ZnO) techniques as advanced oxidation processes in the removal of trimethoprim (TMP) from aqueous solutions. The process consisted of 0.6 g/L of ozone (O3), pH = 7.5 ± 0.5, TMP with a concentration of 0.5–5 mg/L, ZnO with a dose of 50–500 mg/L, 5–30 min reaction time, and 30–180 min contact time with UV radiation (6 W, 256 nm) in a continuous reactor. The high removal efficiency was achieved after 25 minutes when ZnO is used in 1 mg/L TMP under an operational condition at pH 7.5. When the concentration of the pollutant increased from 0.5 to 1, the average removal efficiency increased from 78% to 94%, and then, it remained almost constant. An increase in the reaction time from 5 to 25 minutes will cause the average elimination to increase from 84% to 94%. The results showed that the efficiency of O3/ZnO process in the removal of TMP was 94%, while the removal efficiency of UV/ZnO process was 91%. The findings exhibited that the kinetic study followed the second-order kinetics, both processes. With regard to the results, the photocatalyst process and catalytic ozonation by ZnO nanoparticles can make acceptable levels for an efficient posttreatment. Finally, this combined system is proven to be a technically effective method for treating antibiotic contaminants.

Background: Persian Gulf is one of the most important ecosystems in the world that in recent decades has been exposed to various environmental pollutants such as heavy metals from human and natural activities. Therefore, the aim of this study investigates the concentration of heavy metals (cadmium, lead, copper and zinc) and ecological risk assessment of them in coastal sediments in of Bushehr province in Persian Gulf. Methods: In order to assess the concentration of metals, 54 stations along the coastal zones were selected and in each station three samples of sediment and plant were taken. After preparation and digestion of the samples, the concentrations of these metals were determined by using polarography. Results: The average of total concentration of detected metals Zn, Cu, Pb and Cd in sediment 52.40 ± 2. 62, 34.99±2.76, 11.53 ±2.01 and 2.41± 0.89 μg/g, respectively. Also, the results of comparison of heavy metals concentration in coastal areas in Bushehr Province (Jam, Deir, Bushehr, Dashti, Genaveh and Deilam) with ANOVA test showed there was a significant difference between the concentrations of sediments in different coastal areas. The results showed that the Pollution Load Index (PLI) and ecological risk represents less to moderately pollution in the region. Also, the environmental risk of metals in the region was evaluated as (Cd>Cu> Pb> Zn). Conclusion: According to the results, the pollution and ecological risk of metals in the region for Zn, Cu and Pb is low but for Cd is moderateevaluated

This paper investigates cyanide photodestruction (at pH 9) using the S, N-TiO2 photocatalyst synthesized by the sol-gel method and stabilized on glass microbeads. The main raw materials were thiourea, as a source of N and S, and tetra butyl ortho titanate. The effects of S and N doses, visible light (a 400W light), sunlight, irradiation time, and different initial cyanide concentrations (50, 100, 200, and 300 ppm) were studied on cyanide photodestruction. Cyanide concentration was measured by the titration method and the photocatalyst film was characterized by X-ray diffraction (XRD), UV-Vis diffuse reflection spectroscopy (DRS), Scanning Electron Microscopy (SEM), and Energy dispersive X-ray (EDX) analysis. XRD patterns and SEM images were used to determine the nanoparticle size of the photocatalyst on glass microbeads. EDX and DRS analyses confirmed the presence of S and N as well as the activity of the photocatalyst in the visible region, respectively. The S, N-TiO2 film with 0.25 g Thiuourea proved to be the best cyanide photodestruction agent in the visible light. Based on the results obtained, S, N-TiO2/ glass microbead was capable of destroying cyanide (50 ppm) by up to 94% in the visible light and by approximately 100% in the sunlight. The results also indicated that S, N-Tio2/scoria stone was capable of destroying cyanide by 85% in the visible light and by 94% in the sunlight within 4 h. The reaction kinetic for all cyanide concentrations and two photocatalyst substrates were described by a first order equation. Finally, it was concluded that the S, N-TiO2 stabilized on glass microbeads could be effectively used as a new method for treating wastewater containing free cyanide under the sunlight.

Phenolic compounds are among the priority pollutants due to their adverse effects on human health and other living organisms. Advanced Oxidation Processes (AOPs) offer promising prospects for the removal of pollutants in water and wastewater due to their high efficiency as well as acceptable health and environmental effects. Persulfate, especially when used with iron, is far stronger than many other oxidants with respect to oxidation properties since it produces sulfate radicals which create a higher oxidation potential. In this research, efforts have been made to achieve the best conditions for phenol removal from aqueous environments by activating persulfate with iron ions. The experimental design was accomplished using the Taguchi statistical method and the Minitab 16 software. For the purposes of this study, four factors, each with five levels, were considered to determine the optimal conditions for phenol removal. The optimum conditions for phenol removal by integrated persulfate/iron ions were found to comprise a contact time of 120 minutes, a persulfate/iron molar ratio of 5/4, and PH=3. Phenol removal efficiencies of 94.93%±0.708 and 58.21%±0.675 were obtained under the optimum conditions for the experimental minimum (50 mg/l) and maximum (750 mg/l) phenol concentrations, respectively. The results revealed that among the parameters affecting the process, environmental pH with 54.80% and persulfate concentration with 11.05% have the highest and lowest effects, respectively. It is expected that this process is also capable of removing phenol from industrial wastewaters with removal efficiencies in the range of 59‒95%.

Nitrogen in treatment plants effluent causing problems such as oxygen depletion, toxic impacts on aquatic organisms, eutrophication, and negative impacts on public health. The aim of present study was to determine the performance of integrated system activated sludge/nitrifying trickling filter to improve nitrification in the wastewater treatment plant of Isfahan. In this applied experimental study, an integrated activated sludge (AS) process (in full scale) was used with a trickling filter (TF) (in semi-industrial scale). The diameter and height of TF were 1.8 m and 3 m of steel, respectively. The volume of polypropylene media was 8 m3 and surface area of 240 m2/m3. The hydraulic loading rate during the startup period was 2.4 m3/h which was raised to 7.2 m3/h in the operation period. Flow rate, BOD5, COD, pH, TKN, N-NH3, N-NO2-, N-NO3-, alkalinity and temperature were measured weekly according to standard methods during the operation period. The effect of filter depth on nitrification was studied in 3.6, 4.2, 5.4 and 6 m and HRT of 3.6 m/h. The samples were analyzed by SPSS. The results showed that the best hydraulic and ammonia loading rate achieved here were 3.6-4.2 m/h and 2-2.5 g N/m2d, respectively. The AS/TF system efficiency were 86 % COD removal, 94 % BOD5 removal, 70 % turbidity removal, 94.4 % TSS removal, 55.5-75.5 % TKN removal and 85 % nitrification, respectively. The highest efficiency to reduce of wastewater pollution and nitrification was occurred in depth 4.5 m. Integration of the activated sludge and trickling filter processes, especially in old wastewater treatment plants is a good way to reduce the amounts of nitrogen in treatment plants effluent.

Aims: This study aimed to comparatively investigate the efficiency of removal of formaldehyde using advanced oxidation process ultraviolet (UV)/S2O82-/Fe2+ and UV/S2O82- from aqueous solutions. Materials and Methods: In this experimental-laboratory study, the UV/S2O82 and UV/S2O82-/Fe2+ processes were used to remove formaldehyde. UV radiation was provided by a low pressure (6 W) UV lamp. Effects of various factors including pH, different irradiation durations, different concentrations of iron ions, initial concentration formaldehyde, and persulfate concentration were evaluated. The remaining formaldehyde concentration in the samples was measured by spectrophotometer at 412 nm wavelength. Results: The results showed that in the UV/S2O82- method, the formaldehyde removal efficiency decreased with increasing pH from 3 to 9, while in the UV/S2O82-/Fe2+ method, the formaldehyde removal efficiency increased with increasing pH and concentrations of iron ion. In both methods, as the initial concentration of formaldehyde was increased, its removal efficiency decreased, and the highest formaldehyde removal rate was obtained in UV/S2O82- method at persulfate concentration of 100 mM. However, in the UV/S2O82-/Fe2+ method, the removal efficiency decreased with increasing concentration of persulfate to 100 mM. Conclusion: The results showed that the UV/S2O82-/Fe2+ process was more efficient (87.57%) to remove formaldehyde at high concentrations. Therefore, it is recommended to study the efficiency of this process as one of the clean and environmentally friendly methods at full scale for real wastewater.

Maharloo Lake is one of the most important water ecosystems in Iran, which is nowadays exposed to multiple risks and threats due to poor water management, salt extraction, and heavy metal pollution. In this study, the concentrations of such heavy metals as chromium, copper, zinc, arsenic, cadmium, and lead in both water and salt samples collected from areas in the north and south of the lake were determined by atomic absorption (AA-670G) after the samples had been digested. Results showed that metal concentrations in the salt samples taken from both the northern and southern areas had identical mean values in the order of Cr> Cu> As> Cd> Pb. An almost similar pattern was detected in metal concentrations in water samples taken from the same areas but with a slight difference in the way they were ordered (Cr> Cu> As> Pb> Cd). It was found that both water and salt samples collected from the northern areas had higher metal concentrations, except for that of Pb which was slightly lower. Comparison of the mean values of metal concentrations in the Salt Lake and those of Sirjan, Lar, and Firoozabad salt mines revealed that copper, cadmium, and lead had their highest concentrations in the Salt Lake while arsenic and chromium recorded their highest values in samples taken from Lar and Firoozabad salt mines, respectively. Based on these findings, it may be concluded that the increased metal concentrations observed in samples from both northern and southern areas of the lake are due to the sewage and effluents from urban, industrial, and hospital sources in Shiraz disposed into the lake as well as such other human activities as farming in the areas around the lake, especially in the northern stretches. These observations call for preventive measures to avoid further water quality degradation in the area.

The discharge of phenol and chlorinated compounds, fatty acids, tannin, lignin, and their by-products into receptive waters poses serious hazards for the aquatic life. In this study, the efficiency of a tow-step process of activated sludge-trickling filter (AS/TF) in the removal of inert chemical materials that defy conventional treatment processes was investigated. For this purpose, an integrated activated sludge process (industrial scale) was used sequentially with a trickling filter (pilot scale). Inside a tank with an effective volume of 6.87 m3 was installed 5.78 m3 of polypropylene 2HX media with a specific area of 240 m2/m3. The hydraulic loading rate (HLR) of the trickling filter during the startup period (90 days) was 3.6 m3/h which was raised to 3.6-6 m3/h in the operation period (120 days), with the best effluent quality achieved at HLR=5.4 m3/h. For the purposes of the experiments in this study, four reactors, each 1256 cm3 in volume, were fed the WWTP effluent and concurrently a glucose substrate containing a COD content equal to that fed to the four reactors was fed into two identical reactors; all the reactors were subsequently run for 480 h in aerobic conditions. Nutrients, pH, and DO (as environmental control indicators) as well as soluble and total COD were measured twice daily. The effluent values of soluble inert materials (SI), total soluble COD (STO), degradable suspended materials (XSO), degradable COD (CSO), refractory suspended materials (XI), and degradable soluble materials (SSO) for AS were calculated as 40, 227, 94, 281, 251, and 187, respectively, while the same parameters for the AS/TF were 20, 227, 104, 311, 241, and 207 mg/l, respectively. The results showed that the activated sludge process when combined with the trickling filter has a twofold capability, compared to when used alone, in removing inert COD. It was also shown that treatment levels in conventional WWTPs can be improved by integrating conventional treatment processes.

Background: This study aimed to determine the relationship between the environmental factor, clinical risk factors, and individual variables with mortality due to acute myocardial infarction (MI) in Isfahan. Materials and Methods: This cross-sectional study was performed between April 2012 and March 2013. The data on the patients′ mortality due to MI in Isfahan were obtained from the MI National Registry. The international classification system (ICD10: I21-I22) was used to diagnose MI. The air quality indicators and environmental variables were used to measure the air pollution. Multilevel logistic regression in the Stata software was used to determine the factors associated with mortality in patients and odds ratios (ORs) were calculated. Results: Six hundred eleven patients with MI were studied during 1-year. 444 (72.2%) patients were male and the rest were female. 4.7% of the patients died due to MI. The mean age at MI incidence was 62.2 ± 13 years. Of the air pollution parameters, PM 10 had the maximum mean concentration (49.113 ppm), followed by NOX, NO, NO 2, CO, SO2, and O 3. The adjusted OR of mortality was derived 2.07 (95% CI: 1.5-2.85) for right bundle branch block, 1.5 (95% CI: 1.3-1.7) for ST-segment elevation MI, 1.84 (95% CI: 1.13-3) for age, 1.06 (95% CI: 1.01-1.20) for CO, 1.1 (95% CI: 1.03-1.30) for O3, and 1.04 (95% CI: 1.01-1.4) for SO 2, all of which were considered as the risk factors of mortality. However, OR of mortality was 0.79 for precipitation (95% CI: 0.74-0.84) and 0.52 for angioplasty (95% CI: 0.4-0.68) were considered as protective factors of mortality. The individual characteristics including age, history of MI in the immediate family, hypertension, and diabetes were significantly associated with mortality from MI. The indices of air pollution including SO2, CO, O3, and environmental factors such as the precipitation and temperature were the determinants of mortality in patients with MI. Conclusion: With regards to the factors associated with mortality from MI reported in this study, air pollution and environmental factors, in addition to the risk factors and predictive factors, should be particularly addressed to control the mortality from MI.

Polychlorinated Biphenyls are xenobiotic pollutants, commonly known as PCBs. PCBs could enter the food chain of biological organisms and accumulate in their fatty tissues. Thus, before the discharge of PCBs compounds in the environment, it is necessary to focus on processes and techniques for its removal at their sources. The objective of this research was to investigate the biodegradability of PCBs compounds by Sequencing Batch Biofilm Reactors (SBBR). Acetone and acetic acid were used as solvent in two separate reactors. Organic loading rates (OLRs) were from 0.04 to 0.75 g COD/l-d (maximum concentration of PCBs =0.7 mg/L). The SBBR was operated with four phases including fill, react (aeration), settle (sedimentation/clarification), and draw( decant) during different loading rates. The efficiency of COD and PCBs removal were evaluated. Maximum removal efficiencies of COD was 85% occurred in 0.2- 0.4 g /l-d in the reactor 1(solvent acetone). Also, in reactor 2 (solvent acetic acid) maximum removal rates were recorded as% in OLR of 0.56g COD/ld. The maximum removal efficiency of PCBs was observed at 240 days after start-up of both reactors and was 99%. The results of this research showed that the concentration of priority organic pollutants can be decreased by using biological processes such as SBBR. This study can also indicated that biodegradation of high weight compounds by aerobic bioreactors is a time consuming processes.

High concentrations of heavy metals in soil are toxic to plants, animals, and human beings. The present study was performed in the region in the south of Tehran, which is exposed to pollutants and where the runoff from urban areas is being extensively used for irrigation. Soil samples were collected from 8 stations. The soil distillation method was used to extract heavy metals from the samples and their concentrations were determined using atomic absorption to decide whether the concentrations of such heavy metals as Pb, Cd, Zn, Cu, and Ni exceeded hazardous limits requiring protective measures to be taken. Results showed that the concentration gradients of all the parameters studied increased in the north-south and west-east directions. The average concentrations of Pb, Ca, Zn, Cu, and Ni were 61.12, 1.42, 61.07, 25.85 and 29.22 mg/kg, respectively, in the northern stations, and 76.40, 2.62, 172.05, 69.85 and 37.40 respectively, in the southern stations. Comparison of ±43.7, respectively, in the southern stations. Comparison of the two northern and southern areas revealed that the two northern and southern areas revealed that the northern areas were in contact with more surface runoff, which might have been the cause for the wider distribution of heavy metal concentrations in this region. Moreover, the runoff passing through the deepest parts of the southern region and the extensive application of the flow for irrigation could have caused the higher accumulation of heavy metals in this region. Our findings also indicated that it is necessary to treat surface runoff and to avoid runoff application for irrigation as measures for preventing environmental pollution.

The effectiveness of ozone treatment for improving the biodegradability of recalcitrant pollutants has been proved by investigating the ozonation reaction of Methyl tert-Butyl Ether (MTBE) as a bioresistant gasoline oxygenate. Laboratory scale experiments have been carried out at room temperature by bubbling for 120 minutes ozonated air (3.4 ppm/min) into 3 liter of an alkaline (pH=11.5) aqueous solution (100 mg/L) of MTBE. The experimental results indicated that during the ozonation, complete MTBE degradation occurs in 100 minutes and after this time, ozone consumption goes on very slowly. At the end of the ozonation, after 100 minutes, the initial value of COD (256 mg O2/L) is 98 and corresponds to a relative removal of about 62%. As for MTBE solution biodegradability expressed as (BOD5) / (COD) ratio, during the first 90 minutes, its value regularly increases from lowest 0.01 up to a maximum of 0.68 that corresponds to an ozone consumption of 1.25 mg per each mg of COD initially present in the solution. The research showed that partial degradation of MTBE in the advanced oxidation processes results an increase in its biological degradation. But more oxidation results lower (BOD5) / (COD) ratio. Also the research showed that for idealization of the chemical oxidation conditions of MTBE, it needs to decrease COD to 46-68% before the biological degradation. The experimental results for determining the rate of MTBE removal due to stripping showed that about 14% of MTBE strips out after an hour of sparging with oxygen gas. The fraction of MTBE oxidized and/or striped increases to about 28% (in pH=7) and 70% (in pH=11.5) with ozonation over the same time period.

Background: Regarding failure to establish the statistical presuppositions for analysis of the data by conventional approaches, hierarchical structure of the data as well as the effect of higher-level variables, this study was conducted to determine the factors independently associated with hospital mortality due to myocardial infarction (MI) in Iran using a multilevel analysis. Methods: This study was a national, hospital-based, and cross-sectional study. In this study, the data of 20750 new MI patients between April, 2012 and March, 2013 in Iran were used. The hospital mortality due to MI was considered as the dependent variable. The demographic data, clinical and behavioral risk factors at the individual level and environmental data were gathered. Multilevel logistic regression models with Stata software were used to analyze the data. Results: Within 1-year of study, the frequency (%) of hospital mortality within 30 days of admission was derived 2511 (12.1%) patients. The adjusted odds ratio (OR) of mortality with (95% confidence interval [CI]) was derived 2.07 (95% CI: 1.5-2.8) for right bundle branch block, 1.5 (95% CI: 1.3-1.7) for ST-segment elevation MI, 1.3 (95% CI: 1.1-1.4) for female gender, and 1.2 (95% CI: 1.1-1.3) for humidity, all of which were considered as risk factors of mortality. But, OR of mortality was 0.7 for precipitation (95% CI: 0.7-0.8) and 0.5 for angioplasty (95% CI: 0.4-0.6) were considered as protective factors of mortality. Conclusions: Individual risk factors had independent effects on the hospital mortality due to MI. Variables in the province level had no significant effect on the outcome of MI. Increasing access and quality to treatment could reduce the mortality due to MI.

Aims: This study has been conducted to focus on the localization of the design parameters used for the design of wastewater treatment plants in a region of Iran. Materials and Methods: Three wastewater treatment plants were selected (as models) in a cold weather region of Iran. The main characteristics of the wastewater, such as, flow rate and its fluctuations, total solids, and the organic and nutrient contents, which play an important role in the design and operation of the wastewater treatment facilities, were measured for the selected plants during a year. Results: The averages of the design parameters for the investigated plants, including, biochemical oxygen demand (BOD 5 ), chemical oxygen demand (COD), total suspended solids (TSS), volatile suspended solids (VSS), total Kjeldahl nitrogen (TKN), and total phosphorous (TP) were, 41, 60, 65, 47, 8.3, and 0.93 g/capita, respectively. Wastewater production was 177 lit/cap-day with a maximum and minimum coefficient of 1.76 and 0.29, respectively. Conclusions: Using design parameters based on the local characteristics and the real-world conditions of the wastewater, can result in more+operational efficiency in the wastewater plants. It is suggested that the results of this study can be applied to the design of wastewater facilities throughout Iran, with the same local conditions.