Noise pollution in urban environments: a study in Yazd city, Iran

One of the most important sources of noise pollution in urban areas is traffic noise. The aim of the present study was to determine noise pollution in the different parts of Yazd city in 2010 and to compare them with current standard levels.In total, 135 samples were obtained from both residential and commercial areas according to the ISO 1996-2002 method in order to measure noise pressure levels. Locations included 10 streets and 5 squares of the city and the measurement times were considered in the morning, afternoon, and the evening. Noise level was determined in A-weighted by sound level meter model 2232. Results showed that the rate of background noise in Yazd city was high, as it was 71.2±4.4, 66.2±3.7, and 60.3±4 in the L10, L50, and L90, respectively. The mean level of maximum noise pressure was 74.3 dB(A)(Lmax), and the mean continuous sound equivalent level was 66.7 dB(A) (Leq). Comparing the noise level obtained in the present study to the standard level, it can be obviously concluded that the noise levels are higher than that of acceptable levels in most parts of the city. So, different preventive countermeasures such as increasing public awareness through educational programs and technical controls for the future development of the city are crucial

Applying job hazard analysis and William Fine methods on risks identification and assessment of jobs in hot rolling steel, Iran

Background and purpose: Comprehensive evaluation of jobs in industries is a practical and effective method that could identify the jobs and industries with negative effects on the environment. This study identified environmental hazards of hot rolling process and assessing their risks. Materials and methods: An observational study was carried out in which identification of human activity and job’s risks in production hall of Kavir Steel Complex was done according to ISO 14001 approaches (pollutant emissions to air, discharges to water, energy consumption, energy released as heat, wastes, side products, etc) by Job Hazard Analysis method (JHA). Then the risks identified were prioritized and assessed using William Fine method. Results: We identified 205 environmental hazards (in 9 groups) associated with production personnel (n= 81), mechanics and maintenance personnel (n= 44), bed personnel (n= 9), personnel of cleaning services (n= 33), and water plant personnel (n= 38). The highest and lowest rate of risks were due to creation and distribution of wastes (n= 73) and corrosion and depreciation of equipment, (n= 1), respectively. Conclusion: The production personnel were mainly responsible for environmental emissions. The leading causes were stress and anxiety about stoppage of production, payment reduction, and lack of awareness and workers and supervisors on environmental issues. © 2017, Mazandaran University of Medical Sciences. All rights reserved

Study of efficacy of date kernel ash on removal of nitrate from aqueous solutions (isothermic and kinetic study)

زمینه و هدف: در چند دهه گذشته، حضور غلظت بالای نیترات در آب آشامیدنی به یک نگرانی جدی تبدیل شده که باعث بروز اختلالاتی در سلامتی انسان به خصوص اطفال می شود؛ که با استفاده از روش های فیزیکی- شیمیایی و بیولوژیکی می توان آنرا حذف نمود. در این تحقیق میزان حذف نیترات از محلول های آبی با استفاده از خاکستر هسته خرما، مورد بررسی قرار گرفت. روش بررسی: در این مطالعه تجربی که در مقیاس آزمایشگاهی انجام شد، اثر غلظت اولیه نیترات (50، 100 و 150 میلی گرم بر لیتر) با PH (3، 5، 7 و 9)، زمان ماند (15، 30، 60، 120 و 180 دقیقه) و وزن جاذب (4/0، 6/0 و 8/0 گرم) مورد بررسی قرار گرفت. غلظت نیترات با استفاده از دستگاه اسپکتروفتومتر در دو طول موج 220 و 275 نانومتر اندازه گیری شد. کلیه آزمایشات و آنالیز نمونه به روش کتاب روش های استاندارد آب و فاضلاب انجام شد. یافته ها: افزایش دوز جاذب از 4/0 گرم به 8/0 گرم در 100 میلی لیتر از محلول نیترات با غلظت 50 و 100 میلی گرم در لیتر به ترتیب منجر به افزایش راندمان جذب از 75 به 91 و از 53 به 65 گردید. افزایش PH اولیه محلول از 3 به 9 منجر به کاهش راندمان جذب از 52 به 8 شد. داده های به دست آمده در این تحقیق، از ایزوترم فروندلیچ (98/0R2=) و جذب نیترات از مدل سینتیکی شبه درجه دوم تبعیت می کند (999/0R2=). نتیجه گیری: نتایج مطالعه حاضر نشان داد که خاکستر هسته خرما جاذب طبیعی و ارزان قیمتی است که می توان از آن برای حذف آلاینده های زیست محیطی استفاده کرد

Anxiety as a consequence of modern dietary pattern in adults in Tehran-Iran

Food intake patterns in relation to mental health have already been revealed. To investigate the relationship between processed food consumption behavior and anxiety disorder, a cross sectional study was conducted. Overall, 1782 young adults aged 18-35 years were randomly selected using cluster sampling method from 22 districts of Tehran Iran in 2011. Diet assessment was done using a 24 hour recall questionnaire in two times with a week interval. Anxiety level was determined using the validated Speilburger test (Persian version). A proportional odds regression model was used to assess the effect of processed food consumption on anxiety variables. A significant statistical difference was found between men and women in terms of processed food consumption (p<0.001). Adjusting for age, total calorie intake, gender, body mass index, socioeconomic status, and history of sedative drug consumption as well as mental health disorders, the proportional odds regression model showed a significant relationship between increased consumption of processed foods and anxiety (OR = 4.73, 95 CI: 2.89-12.54 for state and OR = 4.91, 95 CI: 2.88-13.99 for trait). Identification, modification and adjusting incorrect food patterns in the community could be considered as valuable steps to turn down nutritional-based health difficulties. (C) 2012 Elsevier Ltd. All rights reserved

Relationship between metabolic syndrome and osteoarthritis: The Fasa Osteoarthritis Study

An association between metabolic syndrome (MeS) and osteoarthritis (OA) has been reported in recent years; however, conflicting findings have been reported regarding this matter. Inhere we evaluated the relationship between different components of MeS and OA in a Fasa osteoarthritis registry (FOAS). Methods: The registry includes all OA cases who referred to Fasa hospital (Iran) since 2013. Overall, 131 patients with OA with a Kellgren & Lawrence (K&L) score >1 and 261 controls were compared. Results: Overall, 82.4% of individuals in the OA group and 40.8% of participants in the control group had MeS (P < 0.001). Patients with OA had a 6.8 (95% CI: 4.1–11.4) higher chance of acquiring MeS. After adjusting for sex, age, and BMI, odds’ ratio (OR) for acquiring MeS in OA group increased to 10.9 (95% CI: 5.5–21.8). Among MeS criteria’s, high waist circumference (WC) has strongest correlation for acquiring OA (OR = 27.535, 95% CI: 6.003–126.306). Conclusion: Our findings revealed that metabolic markers are strongly associated with OA and the addition of each component of the MeS, significantly increases the risk of developing OA, therefore control of metabolic factors and appropriate screening must be considered in health policy making and prevention programs

Evaluations of pH and High Ionic Strength Solution Effect in Cadmium Removal by Zinc Oxide Nanoparticles

For human and environmental health protection, it is necessary to remove excess cadmium in industrial wastewaters before discharging them to environment. Some laboratory experimental batch study was done to evaluate the effects of the initial cadmium concentration, adsorbent dose, pH, ionic strength, and contact time on the cadmium removal efficiency by zinc oxide nanoparticles. All tests were performed in 100 ml solution at constant temperature of 25\ub0C and mixing rate of 150 rpm. The residual cadmium concentration in the solution was determined using flame atomic absorption spectroscopy. Statistical analyses were performed on data using SPSS16 software by applying Mann-Whitney and Kruskal-Wallis tests and the result designing graphs were provided using Excel software. Finally, experimental data were analyzed using adsorption isotherm and kinetic equations. The results show that cadmium removal efficiency increases with an increase in the adsorbent dose and contact time and decreases with the increase in initial concentration of cadmium. Furthermore, it is observed that by raising the ionic strength of solution 30 fold, the adsorption rate is increased from 90.7% to 62.3%. Due to regression coefficient ( 650.99), the adsorption process follows Langmuir isotherms model and pseudo-second order equation. Attending to the outcomes, zinc oxide nanoparticles have proper efficiency in the removal of cadmium from aqueous solutions. So, they can be used in treatment of the wastewaters containing cadmium ions. However, its efficiency is deeply dependant on the ion strength and the interactions of other metals in wastewater

Application of novel Modified Biological Aerated Filter (MBAF) as a promising post-treatment for water reuse: Modification in configuration and backwashing process

Biological Aerated Filter (BAF) reactors due to their plentiful biomass, high shockability, high efficiency, good filtration, availability and lack of need for large land areas, are enjoying from great importance in advanced wastewater treatment. Therefore, in this study, Polystyrene Coated by Sand (PCS) was produced as a novel media and its application in a modified down-flow BAF structure for advanced wastewater treatment was assessed in two steps. In step one, the backwash effluent did not return to the system, while in step two backwash effluent returned to increase the water reuse efficiency. The backwash process was also studied through three methods of Top Backwashing (TB), Bottom Backwashing (BB), as well as Top and Bottom Backwashing Simultaneously (TBBS). The results showed that return of backwash effluent had no significant effect on the BAF effluent quality. In the second step similar to the first one with slight differences, the residual average concentrations of TSS, BOD5, and COD at the effluent were about 2.5, 8.2, and 25.5 mg/L, respectively. Additionally, in step two, the mean volume of disposal sludge/volume of treated water (v(ds)/v(tw)) decreased a large extent to about 0.088. In other words, the water reuse has increased to more than 99.91. The backwash time in methods of TB and BB were 65 and 35 min, respectively; however, it decreased in TBBS methods to 25 min. The concentrations of most effluent parameters in this system are in concordance with the 2012 EPA Agriculture Standards, even for irrigation of Non-processed agricultural crops and livestock water consumption. (C) 2017 Elsevier Ltd. All rights reserved

Preparation and characterization of TiO2incorporated 13X molecular sieves forphotocatalytic removal of acetaminophen fromaqueous solutions

Although stabilizing of nano-particles on porous media is a suitable methods in harness-ing the agglomeration and inactivation of nano-particles, but still release of particles to theenvironment remains the most serious challenges facing toward photocatalysis process.Attachment of nanoparticles through ion exchange may be a promising method to solvingthese defects. In this study TiO2was incorporated into the 13X molecular sieves by addi-tion of the titanyl ion through an ion-exchange of ammonium-titanyl-oxalate as well as thedecomposition of titanyl oxalate salt, which remained on the zeolite through the impreg-nation and calcination process. A part of TiO2on the zeolite was also bound through aTi O Si bond. The investigation of TiO2-HX catalytic potential showed that neutral pH and500 mg/L catalyst were the optimal conditions for acetaminophen removal (1 mg/L) in theUV/TiO2-HX process. The maximum removal efficiency of 95.45% ± 0.8 was attained after75 min contact time. The acetaminophen degradation during the UV/TiO2-HX process wasfollowed a pseudo first order kinetic model with rate constants (Kapp) of 0.8676 h−1. Under theoptimum conditions, maximum synergistic efficiency of 60.07% was acquired. The exper-imental data showed that the UV/TiO2-HX process is effective in acetaminophen removalfrom aqueous solutions

The Efficiency of Peroxone Process in Packed Reactor for Removal of Anionic Surfactants and COD from Carwash Wastewater

Background: Carwash is an industry that consumes large amounts of water and its wastewater contains a variety of pollutants. The aim of this study was to investigate the efficiency of the Peroxone process as a method for wastewater treatment of carwashes. Methods: This study was conducted at laboratory scale. A total of 54 samples were collected from a carwash in Yazd city and COD and anionic surfactants removal percentages were respectively determined by using the standard vial and anionic surfactants method and Methylene Blue Active Substances (MBAS). The process was conducted with an ozone dose of 0.7 mg per min, H2O2 concentrations of 10, 20 and 40 mmol per liter, reaction times of 30, 60 and 90 min and pH of 7, 9 and 11 in a cylindrical reactor respectively. Data were analyzed using ANOVA and through SPSS 18. Results: The removal efficiencies of COD and anionic surfactants increased with increasing pH and reaction time; so that, at pH =11 and after a reaction time of 90 minutes for an ozone dose of 0.7 mg/min and H2O2 concentration of 40 mmol/l, removal efficiency of COD and anionic surfactants were respectively 74.77% and 74.27%. Conclusion: The peroxone process has a good ability for removal of COD and anionic surfactants. Similar studies confirm the findings of this study. Meanwhile, pretreatment methods are recommended for further evaluation of this process