Showing 69 results for Iron
S. Jorfi, A. Rezaee, N. Jaafarzadeh Haghighifard, G.a Moheb-Ali,
Volume 7, Issue 3 (5-2014)
Abstract
Background and objectives: Because of problems dealing with bioremediation including being time consuming, low efficiency and toxicity to biota, application of advanced oxidation processes with higher efficiency and shorter remediation time have been considered for removal of hydrophobic hydrocarbons from contaminated soils. A great interest has been directed to Fenton oxidation because of its simplicity and high oxidation potential. The objective of this study was to determine the Fenton-like oxidation efficiency for pyrene removal from soil using iron nano oxides and Fe2+. Material and Methods: The H2O2/Fe molar ratios of unadjusted with native Fe content of soil, 10, and 20 H2O2 concentrations of 0 – 500 mM pH 3, 5, and 7 and soil samples containing Fe2+, native iron and iron nano oxides were investigated for removal of 100 mg/kg pyrene according to Taguchi experimental design. Results: Fe2+, H2O2/Fe molar ratio of 20, pH 3 and H2O2 concentration of 500 mM were determined as optimum conditions. Under optimum conditions, S/N ratio increased to 39.322 and the pyrne removal reached to 86 % for Fe2+ and 83 % for Fe3+ respectively, after 2 hours of reaction time and pH 3. Conclusion: Fenton oxidation using iron nano oxides under defined optimum conditions and neutral pH, can be a suitable alternative to conventional Fenton for remediation of soils contaminated with pyrene.
S. A. Jozi, S. J. Esmat Saatloo, Z. Javan,
Volume 7, Issue 3 (5-2014)
Abstract
Background and Objectives: Chemical spillage of equipment is possible in petrochemical processes. Occurrence of such event can result in firing and explosion and consequently would bring about some risks to the environment affected. The aim of this study was to assess environmental risks in Olefin Plant, Arya Sasol Petrochemical Company in order to identify environmental risks at producing source. Methods: The basic data was gathered through using the results of monitoring and measurement of ambient air pollutants and stack exhaust gases, safety review method and field observation. For determination the effects of hydrocarbons leakage from equipment on the environment, measuring BTEX in ambient air was performed as per EPA0030 Standard method with using Gas Chromatography at 4 stations of the complex and a portable Testo 350 XL device was used for monitoring stack exhaust gases, from 9 stacks from May 2011 to April 2012. Assessment and risk management tool used in this study was the fault tree analysis method. The main part of the risk assessment in fault tree method is selecting a top event. According to the statistics of accidents and environmental aspects of ethane cracking operations, hydrocarbon leakage is detected as top event and then composition and relationship between risk factors is determined in the form of terminal event, intermediate event and the gate “and” and “or”. With qualitative and quantitative analysis of fault tree of this accident, the main causes of the accident and the likelihood of the top event was calculated for a year. Results: Comparing with other stations, it was found that benzene with concentration of 0.37 mg/m3 in autumn, toluene with concentration of 0.13 mg/m3 in spring, and ethyl benzene with concentration of 0.09 mg/m3 in autumn, and xylene with the concentration of 1.01 mg/m3 in autumn season had the highest concentration. The fault tree developed had 16 events (including final, intermediate, and initial), which were connected to each other with seven logic gates. The maximum error percentage in the terminal events was attributed to the hardware failures such as malfunction in equipment with 55.55 percent followed by human and administrative errors in the next ranking. The highest percentage (22.2%) of the terminal events was related to the gasket unsuitable material the main reason is due to the economic sanctions and the lack of effort to provide high quality products. Conclusion: Most likely occurrence of the final event was related to the gasket unsuitable material (2×10-2). Control action to prevent the occurrence of leakage could be supplying high quality gaskets and the failure is classified in the hardware failure category.
A Eslami, T Ebadi, M Moradi, F Ghanbari,
Volume 8, Issue 1 (8-2015)
Abstract
Background and objectives: Perchloroethylene (PCE) is categorized as contaminant of concern because of its adverse health effects and persistence in drinking water resources. Permeable reactive barrier with zero valent iron (ZVI-PRB) is a passive zone in which chlorinated ethenes are degraded in situ through the chemical reduction mechanism. The objective of the present investigation was optimization and modelling of ZVI-PRB technology for the elimination of PCE from the aqueous environment using response surface methodology. Materials and methods: In order to simulate ZVI-PRB, a column filled with silica sand and ZVI was used. effects of three variables including pH, column height or barrier thickness and flow on reductive dechlorination efficiency were assessed. Design of experiment, modelling, and data analysis were carried out using response surface method. Results: The dechlorination efficiency was about 93% under optimum conditions (pH=5, 26 cm column height and 2 mL/min flow rate). The ascending trend of pH along the column revealed that the reductive condition was dominant within the column. The R2 value of 0.98 also indicated good fitness of the experimental results and model predictions. Conclusion: Based on the results, ZVI-PRB technology has high efficiency in dechlorination of PCE. Likewise, regarding to no need of energy consumption, abundance of iron, no production of harmful by-products and cost-effectiveness, ZVI-PRB is propounded as a stable, green, and environmental friendly technology in groundwater remediation.
S Valizadeh, Z Shekari,
Volume 8, Issue 2 (8-2015)
Abstract
Background and Objective: Significant increase in population and as a result, the production of excessive waste has recently made attention to municipal solid waste management a necessary issue. The objective of this study was to use matrix-based EIA process in order to determine best waste management option in Birjand City and to suggest appropriate solutions to managers and planners of this city. Materials and Methods: Assessing the environmental impacts of waste management options was done using Iranian Leopold Matrix. Through this method, the environmental impacts of waste management options were determined in the Birjand City. The options were Open dumping, Recycling, Composting, and Sanitary damping. Results: The results indicated that Open dumping with a final score of -3.06 had the highest environmental impact and was introduced as the fourth preference. In addition, composting with final score of -2.34 has the lowest environmental impact compared with other options. Conclusion: About 76.95% of the composition of municipal solid waste of Birjand City is household waste therefore, putrescible organic materials are the predominant waste. Thus, according to the results of the Iranian Leopold matrix method, composting option was introduced as the first priority and the most logical option for waste management in the Birjand City.
K Yaghmaeian, N Jaafarzadeh, R Nabizadeh, H Rasoulzadeh, B Akbarpour,
Volume 8, Issue 4 (3-2016)
Abstract
Background and Objective: Arsenic is one of the most toxic pollutants in groundwater and surface water. Arsenic could have lots of adverse impacts on human health. Therefore, access to new technologies is required to achieve the arsenic standard.
Materials and Methods: The present study was conducted at laboratory scale in non-continuous batches. The adsorbent of zero-valent iron nanoparticles -Chitosan was produced through reducing ferric iron by sodium borohydride (NaBH4) in the presence of chitosan as a stabilizer. At first, the effect of various parameters such as contact time (5-120 min), pH (3-10), adsorbent dose (0.3-3.5 g/L) and initial concentration of arsenate (2-10 mg/L) were investigated on process efficiency. Then optimum conditions in terms of contact time, pH, adsorbent dose and initial concentration of arsenate were determined by RSM method. Freundlich and Langmuir isotherm model equilibrium constant, pseudo-first and second order kinetic constants were calculated. The residual arsenate was measured y using ICP-AES.
Results: The optimum values based on RSM for pH, absorbent dose, contact time, and initial concentration of arsenate were 7.16, 3.04 g/L, 91.48 min, and 9.71 mg/L respectively. Langmuir isotherm with R2= 0.9904 for Arsenate was the best graph for the experimental data. According to Langmuir isotherm model, the maximum amount of arsenate adsorption was 135.14mg/g. . The investigation of arsenate adsorption kinetics showed that arsenate adsorption follows the pseudo-second kinetics model.
Conclusion: This research showed that the adsorption process is depended on pH. With increasing pH, the ability of amine groups in chitosan are decreased to protonation, caused to decrease the efficiency of arsenate removal at high pH.
M Sabouhi , F Nejadkoorki, H.r Azimzadeh, M.s Ali Taleshi,
Volume 9, Issue 1 (6-2016)
Abstract
Background and Objectives: The presence of industrial workshops has increased urban pollution. This study aimed to investigate the heavy metal pollutants of Yazd battery repairing workshops and to identify the ecological and environmental effects resulted.
Materials and Methods: This descriptive cross-sectional study was carried out in Yazd. In this regard, the city was divided into three parts on the basis of geographical features. Then, 30 workshops were selected from each part through stratified random sampling method. Heavy metals (Pb, Cd, Cr, Zn, Cu, Fe, Mn) in the floor were measured using atomic absorption spectrophotometry (AAS). The impacts assessment of heavy metals was evaluated using environmental potential risk index (RI), cumulative pollution index (IPI), pollution coefficient factor (Cf), and the degree of modified contamination (mCd) and Pearson’s correlation statistical test.
Results: The trend of heavy metals concentrations in floor dust particles of workshops was as Fe>Cu>Pb>Zn>Mn>Cr>Cd. Therefore, the average concentrations of Fe and Cd in the samples were 27011.52 ±4721.05 and 78.25±21.07 mg/kg respectively. The results of the RI showed that heavy metal of floor dust had very high danger (2816.29). The mCd value was as 63.35 indicating these workshops were at severe contamination class. The value of Cf was as 304.17 revealing that these workshops were at very severe contamination class.
Conclusions: This research showed that the high concentration of heavy metals in battery repairing workshops is due to the interaction of heavy metals of industrial wastes components, including electrical wastes and battery with the dust having mankind origin.
N Naqshband, M Askari Hesni,
Volume 10, Issue 2 (9-2017)
Abstract
Background and Objective: Glyphosate is a non-selective, systemic herbicide that can control most plants, but it has harmful effects on organisms, especially aquatic animals. Static bioassays were made to determine acute toxicity of glyphosate and its effects on haematological parameters and behavior changes of common carp (Cyprinus carpio).
Materials and Methods: Common carp were exposed to different concentrations of glyphosate (5, 10, 20, 30 and 40 mg/L) and a control group for 96 h. After that, blood and plasma factors were measured in blood samples. Mortality rate and fish behavioral were recorded during the experiments. LC50, LOEC, NOEC and MATC were calculated by Probit software according to mortality rate in any treatment.
Results: In the early period of the experiment, fish in toxic media were jumping in water and showed high movements. Then after, the behavior such as breathing in surface, loss of balance, weakness and finally death were observed in the different treatments. LC50 value and 95% confidence limit of glyphosate in 24, 48, 72 and 96 h were 36.09, 30.46, 21.78 and 20.05 mg/L for common carp, respectively. The LOEC, NOEC and MATC were calculated as 6.66, 4.73 and 2.005 mg/L. The Significant changes that were observed in blood factors included RBC, WBC, Hct, Hb and plasma factors such as total protein, glucose, cortisol and other factors when the pesticide concentration was increased (p<0.05).
Conclusion: Results showed that glyphosate had a high effect on common carp and it its physiology and immune system. Haematological parameters may be used as an environmental health diagnostic test and stress indicator for agriculture pesticides in aquatic ecosystems.
M Ghodrat, E Asrari,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Excessive consumption of antibiotics and the entrance of the potentially hazardous substances to the environment has become one of the environmental concerns. Today, adsorption is one of the efficient and reliable methods for the removal of this class of compounds. The aim of this study was to synthesize chitosan-Fe3O4 and to compare the efficacy of removing erythromycin antibiotics from aqueous humorous media by this adsorbent and chitosan.
Materials and Methods: The structural properties of the synthesized adsorbent were analyzed by TEM, PSA, VSM techniques. Various parameters including pH (1-11), contact time (0-60 min), adsorbent concentration (1-5 g/L), and initial concentrations of erythromycin (5-50 mg/L) was evaluated for the removal efficiency. For data analysis, Excel software was used. The equilibrium constant and the kinetic constants were calculated from the first-order kinetic model using Freundlich and Langmuir isotherms.
Results: The results indicated that increased pH and initial concentration of erythromycin increased the dose of adsorbents and the contact time of removal efficiency. The highest absorption efficiency at pH of 3 for both adsorbents, the contact time 30 min for modified chitosan and 50 min for chitosan, the dose of adsorbent 2 g/L for modified chitosan, and 3 g/L for chitosan and the initial concentration of erythromycin for each of the two adsorbents was 10 mg/L and the erythromycin adsorption by both adsorbents follows the Langmuir isotherm and the pseudo second order kinetics.
Conclusion: According to these results, chitosan modified with Fe3O4 can be used as a more effective adsorbent than chitosan for removal of erythromycin by adsorption method.
Mr Jelokhani-Niaraki, F Hajiloo, L Hasanzade,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: Noise pollution causes many physiological, psychological, economic and social effects on human life. This issue is more important in the environment of industrial workplaces. This research aimed to adopt the functions of GIS for evaluating and spatial analysis of noises in industrial environments.
Materials and Methods: At the initial step, the spatial data for industrial halls were collected and stored as map layers into GIS database. Then, the noise pollution data sampled. The data, including the locations and values of sound pressure levels, were used for the relevant spatial analyses.
Results: The analyses included: the estimation of sound pressure levels in different areas of halls and at the given distance from machines, determination of noisy areas, development of sound noise risk map, interpolation of sound pressure level data, prioritization of the sound sources (i.e., machines) for a given point, prediction of sound pressure levels by moving machines, and optimal site selection and distribution of machines. The mean of noise pressure level was 95 dB for knitting hall, 93 dB for spinning hall 1 and 88 dB for spinning hall 2.
Conclusion: GIS plays a key role in the assessment of noise pollution in industrial workplaces. It is an appropriate tool to store, analyze, manage, and present all types of sound pressure spatial data. Specifically, the use of such system provides spatial intelligence and could help monitor, detect, control, and solve real word sound noise pollution issues.
H Malvandi, N Hassanzadeh,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: Heavy metals contaminations are readily bioaccumulated in aquatic systems and lead to increased concentrations in food chains, posing a serious threat to human health, water-related organisms and aquatic ecosystems. The purpose of the present study was to determine the concentration of heavy metals in surface sediments of CheshmehKile River, to evaluate environmental and ecological risk and to determine the degree of contamination of the elements studied.
Materials and Methods: In this study, 25 samples of surface sediment were collected from the CheshmehKile River. The heavy metals content of the samples was measured by inductively coupled plasma-optical emission spectrometry. According to the content of heavy metals in sediment samples, environmental and ecological risk indices were calculated. Also, river contamination was evaluated by comparing the elements studied values with the sediment quality guidelines values.
Results: The mean concentration of chromium, manganese, iron, cobalt, nickel, zinc and arsenic were 41.27, 356.35, 16756.32, 9.17, 11.87, 41.24 and 24.60 µg/g, respectively. Based on the values of the CF and Igeo indices, all of the elements, with the exception of arsenic, showed a low degree of contamination. The indices of Eir and RI also showed the lowest ecological risk at all stations.
Conclusion: The results of this study showed that the surface sediments of CheshmeKile River in Mazandaran province were somewhat contaminated with arsenic. However, fortunately, the river sediments were of good quality from the point of view of the content of chromium, manganese, iron, cobalt, nickel and zinc.
N Shiralipour, Mr Mirzaee Nejad,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Health expenditures and environmental pollution are indicators of development. Therefore, the aim of this study was to examine the effect of health per capita costs and the impact of carbon dioxide emissions (CO2) as an indicator of environmental pollution on the growth of selected developed and developing countries.
Materials and Methods: The effect of health expenditures and air pollution on economic growth was studied based on the data of two groups of developed and developing countries (2000-2015) and the use of econometric methods.
Results: The fitting of the equations confirmed the significant effect of the health expenditure per capita and CO2 emission on the economic growth of both groups of countries. One percent change in these expenditures resulted in 0.029 percent economic growth in the developed countries and 0.054 percent in the developing. Also, the effect of CO2 release on the economic growth was -0.011 and -0.073.
Conclusion: Health has a direct impact on economic growth. Health has a positive effect on the economic growth by reducing health costs (and spending these resources in other areas) and by increasing labor productivity through increasing life expectancy and useful work time. Also, increasing air pollution has a negative effect on the economic growth of these countries.
M Ansari, M Fahiminia, M Farzadkia,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Rural wastewater management is recognized as one of the pillars of sustainable development. Therefore, the purpose of this study was to assess needs and prioritization of establishment of rural wastewater management facilities in order to supply a safe and alternative water source in the provinces of Iran experiencing severe water stress.
Materials and Methods: This is a cross-sectional descriptive study which was carried out in rural areas of the provinces with severe water stress (South Khorasan, Khorasan Razavi, Fars, Isfahan, Yazd, Semnan, Qom, Sistan and Baluchistan) in 2017-2018. In this study, the number of sample rural areas was calculated by Cochran method and the determination of the sample rural area was done by stratified sampling. The data related to the sample rural area was collected using a validated constructor questionnaire.
Results: The results of this study showed that the difference among all the studied provinces in terms of their priority in establishing rural waste water management facilities to provide a safe and alternative water source was very low. The provinces of Isfahan, Semnan and Fars were rated at 76 out of 100, while the provinces of South Khorasan and Sistan and Baluchestan scored 71 points.
Conclusion: With emphasis on comprehensive decision making criteria based on sustainable development, the results of this study showed that the provinces with severe water stress have a high priority regarding the establishment of rural sewage management projects in order to provide a safe and alternative water sources.
P Firouzi, H Aslani, A Aslhashemi,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Nowadays, swimming pools as a sport and entertainment center have found more popularity. Violation of health based standards in terms of physicochemical, microbial and environmental health indices can turn pools into a potential source of disease transmission and spread. Due to the importance of maintaining swimmers’ comfort, health, and safety, the present study was aimed to consider environmental health status and physicochemical and microbial quality of swimming pools water in Tabriz.
Materials and Methods: In this descriptive cross-sectional study, the official checklists of swimming pools (consisting 10 public and 22 private swimming pools) were obtained from Tabriz Health Center. According to the inspections conducted in February 2017 and August 2017, the related information was extracted from the checklist. Data were analyzed using Excel software, SPSS version 23 and Chi-Square test.
Results: The average accordance of the physicochemical parameters with the standards for public and private pools was 67.5% and 65%, respectively. Among the physicochemical parameters, the residual free chlorine showed less accordance with the standards. On average, in the summer 49.5% and in the winter 28% of the pools showed microbial contamination.
Conclusion: The residual free chlorine values in the pool, Jacuzzi and chiller indicated a weak management of pools and a high potential for pathogenicity. Therefore, continual surveillance of the environmental health status and planning for an objective inspection program by the local authorities, especially in private sector, is suggested.
S Khoshyomn, A Heidari, A R Heidari,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: The steel industry is the world's largest consumer of energy. A large amount of iron waste is produced annually, which its use in the steel industry can be economic. The purpose of this study was to investigate the environmental impacts of the steelmaking from iron scrap as a raw material using a life cycle assessment (LCA) method.
Materials and Methods: Simapro software and the ecoinvent database were used to conduct LCA. Data on the steel production process (raw materials, waste, and products) were collected by a questionnaire from a steel plant. Environmental burdens were quantified using ReCiPe, Cumulative Energy Demand (CED), IPCC) Intergovernmental Panel on Climate Change) and water footprints methods.
Results: The results of the ReCiPe method showed that the terrestrial ecotoxicity with a value of 14392 kg 1,4-Dichlorobenzene (1,4-DCB) eq/ton of steel and global warming with 5289 kg CO2 eq/ton of steel, had the greatest environmental impact, respectively. The lowest environmental impact of this process was obtained for freshwater ecotoxicity and human carcinogenic toxicity. The carbon footprint resulting from steelmaking is 5.24 ton CO2 eq/ton of steel. The most important sector of the greenhouse gas producer is the consumption of electricity with a rate of 2900 of kg CO2 eq/ton of steel. The cumulative energy demand of one ton of steel ingot was 73393 MJ, which is three times the global equivalent. The total water footprint for one t of steel was 19.5 m3 of water, which is almost near to the equivalent in Europe.
Conclusion: the use of iron scrap as raw material in the process of steelmaking instead of iron ore has reduced the amount of human toxicity potential and mineral resource consumption.
A Marzban, M Barzegaran, M Hemayatkhah, M Ayasi, S Delavari, Mt Sabzehei, V Rahmanian,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Nowadays, with the increasing environmental issues such as energy crisis, climate change, waste generation and destruction of natural resources and the increase of waste materials due to the development of urbanization, human impact on the environment is one of the most challenging issues of the scientific community. The purpose of this study was to measure the level of awareness and environmental behaviors of Yazd citizens.
Materials and Methods: This cross-sectional study was carried out on 1000 residents of Yazd in 2018 by cluster sampling. The data collection tool was a standard questionnaire for knowledge, attitude and environmental behavior. The score range for the three knowledge, attitude and practice structures was 0-12, 13-65, and 17-55, respectively. Data were analyzed using descriptive statistics and analytical tests at the significance level of 0.05 using spss16 software.
Results: One hundred percent of the questionnaires were completed. Mean score of knowledge and environmental attitude was 8.23 ± 3.92 and 36.15 ± 8.28 (moderate), and of the environmental behavior was 26.19 ± 7.14 (poor). There was a significant statistical difference between knowledge and environmental behavior of women and men. The level of knowledge and environmental behavior of women was higher (p<0.05). The largest source of environmental information was radio and television (42%).
Conclusion: Despite the relatively good awareness and attitude towards the environment, the majority of the people had poor performance due to the environmental behavior. Therefore, environmental awareness cannot be a guarantee of environmental behavior. It also needs to encourage persuasive social conditions and structure and facilitating environmental behaviors.
Kh Ghattavi, A Naji, S Kord,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Marine pollution is growing due to human activities. Continuous increase in plastic production and poor management of plastic waste resulted in a significant increase of this contaminant in aquatic environments. This in turn led to the widespread presence of Microplastics (MPs) with a size of less than 5mm.
Materials and Methods: In this study, frequency, distribution, color and type of MPs in the gastrointestinal tract of fish in Oman Sea were investigated using random sampling, tissue digestion and flotation of MPs.
Results: The total number of the MPs found in the studied species was variable. The highest number of MPs were found in the species belonged to Rastrelliger kanagurta and Nemipterus japonicus (29%) and Saurida tumbil, Trichiurus lepturus and Paragaleus randalli (14%).
Conclusion: The forms mostly observed were belonged to microfibres (86%), fragment (11%) and pellet (3%). The most frequent colors that were detected were in a decreasing order blue, pink and black. The results demonstrated that the highest concentrations of MPs were observed in Ratrelliger kanagurta and Nemipterus japonicus species. The present study provides useful information for further research, and a background analysis to monitore the pollutants in the Oman Sea.
S Fallah Jokandan, M Yegane Badi, A Esrafili, A Azari, E Ahmadi, H Tarhandeh, M Kermani,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: The activities of various industries produce a wide range of pollutants and toxic compounds. One of these compounds is the catechol, a cyclic organic compound with high toxicity and resistant to degradation. Therefore, the purpose of this study was to investigate efficiency of powder activated carbon magnetized with Fe3O4 nanoparticles in the removal of catechol from aqueous solutions by response surface methodology.
Materials and Methods: The co-precipitation method was used to synthesize magnetic powder activated carbon and its properties were analyzed by SEM and XRD analysis. Then, the effect of the parameters such as pH, contact time, absorbent dose, initial concentration of catechol and temperature on the efficiency of adsorption process were investigated using a response surface methodology (Box–Behnken). The residual concentration of catechol was measured by HPLC at 275 nm.
Results: The results showed that the maximum efficiency of the adsorption process was obtained at concentration of 20 mg/L, pH=3, contact time 90 minutes, at 25 °C and absorbent dose of 1.5 g/L. The study of isotherm and kinetics showed that the experimental data of the catechol adsorption process correlated with the Langmuir and pseudo-second order models, respectively. Thermodynamic study of the reaction also expresses the Exothermic and Spontaneous process.
Conclusion: The results showed that the adsorption process using powder activated carbon magnetized with Fe3O4 nanoparticles at acidic pH had better efficiency. As a result, the studied process as an effective, rapid and inexpensive method for removal of catechol from aqueous solutions is proposed. Due to its short reaction time, it is economically affordable process.
K Naddafi, A Mesdaghinia, M Abtahi, Ms Hassanvand, R Saeedi,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Environmental burden of disease (EBD) studies are one of the most important needs for determining the current situation, increasing the effectiveness of health policies and programs and prioritizing environmental health interventions. This review article was evaluated the status of the EBD in Iran based on the results of the latest Global Burden of Disease (GBD) Study, other international studies and national estimates in the country.
Materials and Methods: In this study, the researches on the EBD in Iran were identified by searching in the international and national scientific databases and the search results were studied and analyzed.
Results: The review of the EBD studies showed that based on the results of the GBD study, the share of environmental risk factors in the total burden of diseases in the country in 2017 according to the disability-adjusted life years (DALYs) and deaths were about 8 and 13%, respectively. According to the results of the GBD study, the contributions of environmental risk factors in the attributable DALYs in the country in 2017 (a total value of 1,648,329) were as follows: ambient air PM2.5 for 45.0%, occupational risk factors for 25.1%, exposure to lead for 19.4%, unsafe water source for 5.0%, tropospheric ozone for 1.7%, lack of access to handwashing facility for 1.5%, unsafe sanitation for 1.4%, residential radon for 0.6%, and household air pollution from solid fuels for 0.3%. The total DALY rate and death rate attributable to solar ultraviolet radiation in Iran in 2000 were estimated to be 46.2 and 0.7, respectively. The DALY and the DALY rate attributable to elevated levels of fluoride in drinking water due to dental fluorosis in the country in 2017 were 3,443 and 4.14, respectively. The evaluation of the effect of water fluoridation as an environmental protective factor showed that the intervention by reducing the risk of dental caries could fall the DALY and DALY rates in the country by 14,971 and 18.73, respectively. In the period of 2005-2017, the DALY rate (per 100,000 people) attributable to ambient air PM2.5, tropospheric ozone, residential radon, and occupational risk factors rose that the result increases the importance of the preventive measures and controls of these risk factors.
Conclusion: There was a considerable difference in the burden of disease attributed to each risk factor in various international studies as well as between national and international studies. The results of national studies on the burden of diseases attributable to environmental risk factors are considered to be more reliable and practical due to the application of more detailed data and conducting subnational evaluations; therefore, the strengthening and continuing these studies at the national and sub-national levels with regard to priorities, needs, and spatiotemporal trends using domestic reliable data and information are necessary and strictly recommended.
Z Esdaki, R Ansari, F Ostovar,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Due to the existence of industries such as stainless steel, the presence of nickel (II) ions in water and wastewater has been reported at high concentrations. Removal of nickel (II) ions from wastewater and the environment are of primary importance. In this study, iron (III) oxide nanoparticles were studied as an adsorbent for removal of Ni (II) ions from water in the batch equilibrium system.
Materials and Methods: FT-IR, SEM and XRD techniques were used to characterize the structure of the sample. To determine the optimum adsorption, the effect of important parameters such as pH, contact time, adsorbent weight and initial concentration were investigated. Also, thermodynamic study (Gibbs standard energy variations, enthalpy and entropy), isothermal studies (absorption capacity) and kinetic studies (absorbent effect with time) were investigated.
Results: The results showed that the magnetic adsorbent had the highest removal efficiency of nickel (II) at pH 7, contact time 60 min, adsorbent dosage of 200 mg, and maximum removable concentration of 400 mg/L.
Conclusion: With thermodynamic studies, it was determined that the reaction was endothermic and the spontaneous process was controlled using the entropy factor (ΔG°=-2.7 KJ/mol, ΔS°=+165.17 J/mol.K). In order to better understand the mechanism of adsorption, kinetics studies were carried out using the pseudo-first-order and pseudo-second-order models. Then, Langmuir and Freundlich adsorption isotherms were investigated to determine the adsorption capacity, and it was found that the adsorption data were well fitted to Freundlich model and the maximum adsorption capacity was 43.5 mg/g, which indicated high adsorption capacity and its multi-layers.Then, Langmuir and Freundlich adsorption isotherms were investigated and it was found that the adsorption data were well fitted to Freundlich model and maximum adsorption capacity (qmax=43.5 mg/g) was obtained which indicates good adsorption capacity of adsorbent and its multi-layers.
Kh Ghattavi, A Naji,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Microplastics (MPs) are well-known emerging contaminants in the marine environment. A key route by which MPs can directly affect marine life is through ingestion.
Materials and Methods: In order to investigate and measure MPs in the Persian Gulf, random sampling and digestion of tissues and flotation of MPs were used. This method has been used to study the frequency, distribution, shape and color of MPs in in the digestive system of fish in the Persian Gulf.
Results: According to the results, the highest concentration of extracted MPs were found in Sillago sihama (62%), Diagramma pictum (26%), Lutjanus johnii (6%), Otolithes ruber (5%), Epinephelus coioides (1%). However, MPs were not observed in Scomberomorus commerson.
Conclusion: The relative contribution of different forms of MPs in any fish showed that microfibers with the most abundant forms of MPs and fragments and films were observed to have the lowest concentration of 11% and 2%, respectively. Based on our results, it is suggested that Sillago sihama is suitable indicator of MPs contamination among studied fish in the Persian Gulf. Ingestion of MPs provides a potential pathway for the transfer of plastic additives, metals, PAHs and other POPs to wildlife and human consumers of fish. Therefore, more comprehensive investigations on MPs and nano-plstics should be conducted in food chain of seafood.
