Showing 27 results for Naddafi
Ramin Nabizadeh Nodehi, Hassan Aslani, Mahmood Alomohammadi, Reza Nemati, Kazem Naddafi, Maryam Ghany,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Irrigation of agricultural crops using wastewater will
increase, in some cases, their growth by 40 to 60 percent. However, this has a
high risks for human health because of the presence of higher number of
pathogenic organisms. The main purpose of this study was to investigate the
feasibility use of Fenton and modified Fenton with copper for the disinfection
of raw wastewater.
Materials and Methods: After primarily laboratory physicochemical and biological analysis, the
disinfection process was performed in three different phases in each process.
First, the disinfectants were injected separately, then we performed
disinfection using Fe++ and cu++ ions combined with hydrogen peroxide in order
to determine synergistic effect of each catalyst. Direct method was used for
fecal coliforms counting.
Results: Hydrogen
peroxide maximum efficiency for inactivation of fecal coliforms was only
0.66log inactivation. Fenton and modified Fenton with copper ions showed a
remarkable effect on the bacterial inactivation so that Fenton and modified
Fenton with 1 and 2 mg/l of Cu++ inactivated coliforms by 4.73, 3.28, and 4.88
log respectively.
Conclusion: Application of HP alone for the disinfection of raw wastewater is not
practicable due to low observed efficiency. However, its combination with ions
such as Fe++ and Cu++ increases HP performance in disinfection and has a
notable synergistic effect on HP
disinfection power, where, in the presence of each catalyst, hydrogen
peroxide can reduce the fecal coliforms of raw wastewater to meet the Iranian
Environmental Protection Agency Standards.
Kazem Naddafi, Mehran Mohammadian Fazli, Ali Reza Mesdaghinia, Simin Nasseri, Mahnaz Mazaheri Assadi, Masoud Yunesian,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Environmental pollution and health risks of dyestuffs
extensively are caused by many industries. Nonbiodegradability of dyes is
important so that different methods are studied for removing them. The use of
white rot fungi is promising technique in this regard. Therefore, objective of
this work is to investigate Rimazol Brilliant Blue Royal decolorization by
immobilized Ganoderma sp. in sodium alginate from aqueous solution.
Material and Methods: This is an experimental study. First, the nutritional, environmental, and
operational conditions of decolorization process were optimized. Then,
efficiency of immobilized fungal cells was investigated. Experimental designs
were provided using fractional factorial methods and quadratic model was fitted
on decolorization data by MiniTab software.
Results: Our findings
showed that type and concentration of carbon source, temperature, and pH were
the most important factors affecting decolorization and statistically
significant. Optimal conditions to 95.3 percent color removal were: glycerol as
carbon source at 19.14 g/L temperature, 27 oC and initial pH, 6.26. Moreover,
decolorization efficiency increased from 75 percent up to 95 percent by improving
process and fungal immobilization.
Conclusion: Ganoderma
fungus has suitable potential to decolorization. Besides, optimization and cell
immobilization can improve its capability. Application of experimental design
to research methodology is important because of decreasing in experiments and
saving resources. It is suggested to use these potentials in environmental
pollution control.
Fatemeh Momeniha, Ramin Nabizadeh Nodehi, Mohammad Sadegh Hassanvand, Amir Hossein Mahvi, Kazem Naddafi,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4 Background and Objective: Dioxins and Furans are dangerous and highly toxic compounds entering to the environment from natural and manmade sources. Having high stability and half-life, these compounds remain for a long period in the medium and bring about severe effects on human beings and the environment. The aim of this study was to identify dioxins and furans emission sources in Iran and to estimate their contribution in emission rate.
Materials and Methods: First, we identified the emission sources of dioxins and furans and then necessary data was gathered by referring to the authorized organizations and filling the prepared UNEP questionnaires. We used Excel software to analyze the data collected.
Results: According to the results obtained, total dioxins and furan emission in Iran in 2010, was 1957 g TEQ/yr out of this amount, 705.8 g TEQ is emitted to the atmosphere and 643.2 g TEQ is residual ash. Therefore, dioxins and furans emission rate was 26.4 µg TEQ/capita in Iran. The most rates of emissions were associated with uncontrolled open burning (732.8 g TEQ/yr) and ferrous and nonferrous metal production (635.7 g TEQ/yr) such as cupper, iron, and steel.
Conclusion: Our findings showed that the emission rate of Dioxins and Furans is much higher in Iran compared with other countries and appropriate management strategies are required to control these dangerous pollutants.
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Mohammad Sadegh Hassanvand, Ayoub Torkian, Mohammad Reza Sahebnasagh, Kazem Naddafi, Mohammad Kazem Moayyedi,
Volume 5, Issue 3 (21 2012)
Abstract
MicrosoftInternetExplorer4
Background and
Objectives: Wind-induced particulate air pollution from iron ore piles can
causes environmental and economic problems for steel industries. In this
experimental study, the effectiveness of various additives in reducing
particulate air pollution from iron ore piles was investigated in a laboratory
wind tunnel.
Materials and Methods: The experimental set up consisted of a
prismatic pile and a wind tunnel. Four different wind speeds of 4.3, 5, 7 and
11 m/s was used in the study Municipal
water, quick lime (2%), seawater, treated industrial wastewater and Polylatice
(0.25%) were used as additives to stabilize the upper layer of the pile.
Results: Emission factors for
non-stabilized (without additive) piles at 4.3, 5, 7 and 11 m /s wind speeds
were 46.7, 73.2, 1025.4 and 13768.7 g/m
2, respectively. Stabilized
piles with 2.6, 2.7, 2.8, 2.7 and 2.8 percent additive (moisture content of the
upper layer of the pile) for municipal water, Polylattice (0.25%), treated
industrial wastewater, seawater and quick lime (2%) indicated a decrease of
99.4%, 100%, 99.3%, 99.5% and 99.5% particulate emission reduction,
respectively.
Conclusions: Proper selection and use
of additives on iron piles has the potential for decreasing more than 99% of the wind-induced particulate
emissions. Operational factors such as covered area, spray frequency, pile
geometry, seasonal adjustments related to ambient temperature and humidity,
wind speed and operator training need to be an integral part of the pollutant
reduction program.
Soheila Rezaei, Kazem Naddafi, Hossain Jabbari, Masoud Yonesian, Arsalan Jamshidi, Abdolmohamad Sadat, Alireza Raygan Shirazinejad,
Volume 6, Issue 1 (5-2013)
Abstract
Background and Objectives: In recent years exposure to fine airborne particles has been identified as an important factor affecting human health. Epidemiological studies have showed that the aerosol laden air can be an agent for microorganisms’ dispersion. Ignoring internal sources, ambient air quality significantly affects indoor air quality. Since people spend most of their times in the indoor spaces and little data are available on the general understanding of the indoor air quality, therefore, the aim of this study is to determine the particulate matter concentrations in indoor and ambient air of Tehran Children Medical Center Hospital.
Materials and Method: PM10/PM2.5 samples were collected in the indoor environment of the Tehran Children Medical Center Hospital and its adjacent outdoor environment by a portable GRIMM dust monitor model 1.108 from November 26 to March 10, 2007. The places of sampling for indoor and ambient air were in the patient room and the roof of the hospital respectively.
Results: The results showed that indoor PM10 level was higher than WHO standards in 80% cases in patient room, whereas, for indoor PM2.5 level, this value was 42 and 64% more than the EPA standards and WHO standards respectively. The relationship between outdoor and indoor particulate matters was examined by linear regression analysis. The indoor particulate matter levels were correlated with the corresponding ambient air ones.
Conclusion: Our analysis revealed that infiltration of ambient air could substantially increased indoor pollutants and thereby influences the indoor air quality.
Mohammad Reza Mehrasebi, Mansour Baziar, Kazem Naddafi, Mehran Mohammadianfazli, Ali Assadi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: Soil pollution by oil compounds is a serious environmental and ground water problem throughout the world. Total petroleum hydrocarbons (TPH) are a combination of many distinctive compounds. Some of these compounds in exposure with human and animal can cause cancer, disorder central nervous system, liver and lungs affects. The objective of this research was to investigate gasoline removal (C10 – C 28) using Brij 35 and Tween 80 from polluted soil. Materials and Methods: In this experimental study, the efficiency of soil washing with nonionic surfactants (Brij 35, Tween 80) for remediation of gasoline polluted soils was studied. The effects of soil washing time, agitation, surfactant concentration, and pH on the removal efficiency were studied. Results: The results showed that gasoline removal efficiency increased with increasing agitation speed and washing time. In addition, it was found that removal efficiency of gasoline was decreased by increasing surfactant concentration. But, increasing pH did not have remarkable effect on removal efficiency of gasoline. The efficiencies of Tween 80 and Brij 35 for removal of gasoline under optimal condition were 70 -80 and 60- 65% respectively. Conclusion: The results showed that soil washing with non ionic surfactants was effective in removal of gasoline from polluted soil and it can be recommended for treating surface soil polluted.
Farin Fatemi, Hamed Mohammadi, Ali Ardalan, Kazem Naddafi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: On August 2012, two earthquakes measured 6 and 6.2 on the Richter scale took place in Eastern Azerbaijan province. Environmental Health Department is accounted as one of the main units for providing and supervising environmental sanitation services at the emergencies, therefore, the objective of this study was allocated to assess environmental health response performance in recent earthquake.
Material and Methods: Through multi-stages stratified sampling, we selected 8 and 4 villages from the earthquake zones of Heris and Varzaghan respectively. The collecting data tools in this research were the WHO checklist in 7 categories, 14 subcategories, and 37 environmental health activities and also the minimum standards of Sphere Project checklist. The status of environmental health in each village was assessed using the mentioned checklists. This study was carried out with attendance of research team in earthquake zones 21 days after the occurrence of earthquake.
Results: Among the 37 environmental health activities, 7 activities were the joint ones, which Environmental Health Department had to carry it out with the coordination of other related organizations. In other words, the environmental health has the supervising role in these activities. Totally, such activities had more nonconformities compared with the activities in which environmental health was administered as the main responder. The details of results have been expressed in the full text.
Conclusion: Providing intra-sector coordination, prioritizing the needs of the affected population and considering the principles of community based management in the natural disaster are proposed as the recommendations of this study.
Mahdi Sadeghi, Kazem Naddafi, Ramin Nabizadeh,
Volume 7, Issue 2 (10-2014)
Abstract
Background and objective: Perchloroethylene is a chlorinated hydrocarbon used as a solvent in many industries and services activities such as dry cleaning and auto industry as degreasing. We carried out a bioassay using Daphnia Magna in order to determine the ecological effects of wastewater treatment through applying advanced oxidation processes (ultrasonic, ultraviolet irradiation and hydrogen peroxide processes) for removal of perchloroethylene. Materials and Methods: Due to the sensitivity of Daphnia and reports indicating this species is the most sensitive aquatic invertebrate to a variety of organic compounds, toxicity of perchloroethylene and its intermediate degradation products during applying different processes was tested using Daphnia. Lethal concentration (LC50) and toxic units (TU) were determined. In to determine toxicity of perchloroethylene, its stock solution was prepared at a concentration of 100 mg/L. Then, nine samples each containing 0 (control), 5, 10, 20, 30, 40, 50, 75, and 100% by volume of the primary stock solution were prepared. To determine the toxicity of the intermediate products of perchloroethylene by ultrasonic, photolysis, photolysis with hydrogen peroxide and photosonic processes, an initial concentration of perchloroethylene for each reactor (100 mg/L) was taken. All experiments were carried out at the Laboratory of Microbiology, Faculty of Health, Tehran University of Medical Sciences, Iran. Results: It was found that the 24 h LC50 for perchloroethylene on Daphnia Magna was 35.51 mg /L. The 48 h, 72 h and 96 h LC50 of perchloroethylene were 28.058, 21.033, and 19.27 mg/L respectively. Toxicity of perchloroethylene was decreased after oxidation processes. Conclusion: The toxicity after hybrid processes was lower than the single processes. The toxicity reduction was the same during all time period. Hence, the hypothesis of reducing toxicity of the intermediate products of perchloroethylene degradation after the abovementioned processes is acceptable. It is noteworthy that although there are different intermediate compounds in the effluent of various chemical oxidation processes, , but they are less toxic compared with the original perchloroethylene this may be due to the partially concentration of intermediate products that will decrease toxicity.
R Nabizadeh, K Naddafi, A Jonidi Jafari, M Yunesian, A Koolivand,
Volume 7, Issue 3 (5-2014)
Abstract
Background & Objectives: Remaining crude oil in storage tanks lead to accumulation of oily sludge at the bottom of the tank, which should be treated and disposed of in a suitable manner. The aim of the present study was to investigate the efficiency of chemical oxidation using H2O2 and Fenton’s reagent in removal of Total Petroleum Hydrocarbons (TPH) from bottom sludge of crude oil storage tanks. Materials & methods: In this experimental study, hydrogen peroxide and Fenton’s reagent were added to the sludge in six concentrations including 2, 5, 10, 15, 20, and 30% (w w-1) and TPH was measured for a period of 24 and 48 h of reaction time. The oxidants were added in a single and stepwise addition way, both to the pristine and saturated sludge. The elemental analysis of sludge and TPH measurement were carried out using ICP and TNRCC methods respectively. Results: The mean TPH removal of 2, 5, 10, 15, 20, and 30% oxidant concentrations were 1.55, 9.03, 23.85, 33.97, 41.23, and 53.03%, respectively. The highest removal efficiency was achieved in stepwise addition to the saturated sludge. Increasing oxidation time from 24 to 48 h had a little effect on increase in TPH removal. Moreover, the removal efficiency of H2O2 and Fenton was nearly similar. Conclusions: Mere application of chemical oxidation is not capable of complete treatment of the sludge but it is an effective process as a pre-treatment step for decreasing toxicity and increasing its biodegradability.
K. Naddafi, M. Gholami,
Volume 7, Issue 3 (5-2014)
Abstract
Background & objective: Synthetic dyes are extensively used in various industries such as textile, leather tanning, plastic, pulp and paper. Since dyes are toxic and even carcinogenic, discharging dye-containing wastewater into the environment poses serious environmental and health problems. Therefore, the purpose of this paper was to evaluate the removal of Reactive Red 120 from aqueous solutions using surface modified natural zeolite. Materials &Methods: The Semnan zeolite was sieved using standard sieves in size of 0.2 - 0.3 mm and then was modified by cationic surfactant. Batch adsorption studies carried out to study various parameters included contact time, initial concentration of Reactive Red 120, pH, and adsorbent dosage. The concentration of dye was measured using a UV-vis Spectrophotometer at the wavelength of 537 nm. Freundlich and Langmuir isotherms and Pseudo-first order and pseudo-second order kinetics were used to analyze the isotherm and kinetic data respectively. Results: The adsorption studies indicated that increasing of the contact time, initial concentration of Reactive Red 120, decreasing pH and adsorbent dosage leads to increasing dye adsorption. Equilibration of Reactive Red 120 adsorption was reached at lapse of 90 min. Moreover, it was found that Langmuir isotherm (R2=0.9814) and pseudo second-order kinetic (R2=0.9814) are well fitted with our data. Conclusion: The results of the study show that Iranian modified zeolite can be used effectively for removal of Reactive Red 120 in comparison with other parts of the world. Considering the cost, availability and ease of modification, it can be used to remove dye in industrial wastewater.
M Abtahi, K Naddafi, A.r Mesdaghinia, K Yaghmaeian, R Nabizadeh, N Jaafarzadeh, N Rastkari, R Saeedi, Sh Nazmara,
Volume 7, Issue 4 (1-2015)
Abstract
Background and objectives: Dichloromethane (DCM) is one of the hazardous contaminants of the environment, especially ambient air that threatens human health at both acute and chronic exposures. In this study, the performance of a pilot-scale hybrid bubble column/biofilter (HBCB) bioreactor was studied for the removal of DCM from waste gas streams at steady state. Materials and methods: The experiments were conducted in four stages with relatively constant concentrations of DCM (approximately 240 ppm) and variable empty bed residence time (EBRT) of 50, 100, 150 and 200 s. In addition to determining DCM removal rate and efficiency, quality parameters of mixed liquor of the bubble column bioreactor were studied and kinetic of biofiltration was analyzed. Results: The average DCM removal efficiency of the HBCB bioreactor at EBRT of 200 and 150 s were 79 and 71% respectively. However, further reduction of EBRT resulted in significantly decreased DCM removal efficiency, so that at EBRT of 50 s, the DCM removal efficiency decreased to 32%. In addition, the EBRT reduction from 200 s to 50 s through increasing DCM loading rate resulted in increasing DCM removal rate from 12.1 to 19.6 g/m3.h. The results of kinetic analysis showed that the kinetic data of biofiltration were in the best fitness with the first order rate equation (R2>0.99 and &epsilon%<2.2) and the DCM removal rate constant was determined 0.0114 s-1. The mixed liquor characterization indicated that the daily adjustment of pH and EC was sufficient to prevent any limitation in the performance of the HBCB bioreactor. Conclusion: This study indicated that the DCM removal rate and efficiency of the HBCB bioreactor were relatively high and the HBCB bioreactor had reliable performance during the variable operational conditions.
K Naddafi, A Beiki , R Saeedi, G Ghanbari, A Niati, L Sori,
Volume 8, Issue 3 (12-2015)
Abstract
Background and objectives: In the outbreak of infectious diseases, the on time epidemiological, environmental, and laboratorial investigations result in rapid diagnosis of cause and source of the outbreaks and decrease the diseases spread and public health loss. Following the outbreak of gastroenteritis in Pardis Town in January 2014, this research was conducted to identify the cause, source, and route of transmission of the outbreak.
Materials and methods: First, the descriptive epidemiological study was conducted using checklist and the stool samples were prepared and analyzed. The drinking water quality in Pardis during and before the outbreak was obtained from National Environmental Health Network. The community water supply system consisting of watershed, water resources, pipelines, storage reservoirs, disinfection systems, and distribution network were inspected and sampling and detection of thermotolerant coliforms and norovirus in water samples were performed according to the Standard Methods.
Results: There were 6,027 patients with symptoms of nausea, vomiting, cramps, mild diarrhea, and mild fever. The distribution of the disease in all age groups, gender, ethnicity, and location was uniform. Out of nine stool specimens, molecular testing of norovirus in six samples was positive. Hazards identified in the water supply system consisted of a water pipe fracture occurred two days before the outbreak, illegal connection of landscape irrigation system to the drinking water supply network, the use of unprotected Fellman wells as the resource of water supply, and discharge of domestic wastewater into the water resource upstream of the Fellman wells. The water samples taken from the Fellman wells had fecal contamination (11 out of 12 samples), but because of weakness and limited experience in identifying norovirus in water samples, norovirus was not detected in the raw water samples.
Conclusion: This study showed that the pathogen came from a single source. Clinical symptoms, epidemiological evidence, the results of analysis of human stool samples, fecal contamination of raw water samples and norovirus resistance to the standard amounts of free residual chlorine in water indicated that the outbreak caused by consumption of contaminated drinking water (discharge of domestic wastewater to water supply system). In order to prevent similar outbreak, resolving the observed bugs in the water supply system and implementation of water safety plan is recommended.
K Naddafi, R Nabizadeh, S Nasseri, K Yaghmaeian, A Koolivand,
Volume 8, Issue 3 (12-2015)
Abstract
Background and Objectives: Remaining of crude oil in storage tanks usually results in accumulating oily sludge at the bottom of the tank, which should be treated and disposed of in a suitable manner. The efficiency of in-vessel composting process in removing total petroleum hydrocarbons (TPH) from bottom sludge of crude oil storage tanks was investigated in the present study.
Material and methods: The sludge was mixed with immature compost at the ratios of 1:0 (as control), 1:2, 1:4, 1:6, 1:8, and 1:10 (as dry basis) with the initial C:N:P and moisture content of 100:5:1 and 55% respectively for a period of 10 weeks. The moisture adjustment and mixing process were done 3 times a day during the composting period. Sampling and analysis of TPH and pH were done every week and every two days, respectively.
Results: TPH removal in the 1:2, 1:4, 1:6, 1:8, and 1:10 composting reactors was 66.59, 73.19, 74.81, 80.20, and 79.91%, respectively. Thus, initial adjustment of sludge to immature compost ratios plays a great role in reduction of TPH. The results of the control reactors indicated that the main mechanism of TPH removal in the composting reactors was biological process.
Conclusions: In-vessel composting by addition of immature compost as amendment is a viable choice for bioremediation of the bottom sludge of crude oil storage tanks.
A Koolivand, K Naddafi, R Nabizadeh, A Jonidi Jafari, M Yunesian, K Yaghmaiean, S Naseri,
Volume 9, Issue 3 (12-2016)
Abstract
Background and Objective: The performance of in-vessel composting process, as one of the most effective methods of oily sludge treatment, depends on factors such as nutrients and temperature. Therefore, it is crucial to investigate the trend of changes of these factors. The aim of the present study was to investigate the trend of changes of organic carbon, nitrogen, phosphorus, and temperature during the composting of bottom sludge of crude oil storage tanks.
Materials and Methods: The sludge was mixed with the immature compost at the various ratios of sludge to compost including 1:2, 1:4, 1:6, 1:8, and 1:10 with the initial C/N/P of 100/5/1 and then was composted for a period of 10 weeks. The process of mixing and moisture adjustment of the mixtures was done 3 times a day during the composting period. Sampling and analysis were performed every week for organic carbon, nitrogen, and phosphorus and every day for temperature.
Results: The research indicated that the concentrations of organic carbon, nitrogen, and phosphorus were decreased sharply during the first weeks of the process and then they were decreased gently. At the final stage of the composting, the ratios of C/N and C/P increased from 20:1 and 100:1 to 26:1 and 166:1, respectively. In addition, the temperature of the reactors was kept in the mesophilic range during the process period.
Conclusion: The similar trend of decrease of organic carbon, nitrogen, and phosphorus in the composting reactors is an indication of decreasing the activity of the microorganisms involved in petroleum hydrocarbons degradation.
K Naddafi, M Yunesian, S Faridi, A Rafiee, S Parmy, Gh Safari, R Nabizadeh Nodehi , K Yaghmaeian, N Rastkari, R Ahmadkhaniha, S Niazi, M Hoseini,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants that are mostly generated during the incomplete combustion. The main objective of this study was to characterize potential sources of PAHs in Tehran.
Materials and Methods:, Samples of PM10 were collected at 10 monitoring stations belonging to Tehran Air Quality Control Company (AQCC) and transferred to laboratory for analysis. Besides, a SKC Flite 2 Air Sampling Pump (SKC, USA) equipped with a sampling head and PM10 size-selective inlet was used at four stations to compare the results obtained by collecting AQCC monitors (AQCCMs) tapes with the standard sampling procedures for assessing the interchangeability of two field sampling methods. The principal component analysis (PCA) and diagnostic ratios were applied to identify emission sources and source contribution.
Results: The average diagnostic ratios of phenanthrene (Phe)/ (Phe+anthracene (Ant)), benzo(a)anthracene (BaA)/ (BaA+chrysene (Chry)), fluorantene(Flu)/ (Flu+pyrene (Py)), and indeno(1,2,3cd) pyrene (IcP)/(IcP+benzo(ghi)perylene (BghiP)) in samples were 0.79, 0.52, 0.43 and 0.38, respectively. These ratios showed that the combustion, especially fossil fuels and motor vehicles, was the main sources of PAHs emission in Tehran. The results of PCA analysis also indicated that 49, 29 and 22% of PAHs sources in Tehran atmosphere were attributed to gasoline-driven vehicles, diesel vehicles and other sources, respectively.
Conclusion: According to the results, the combustion, especially fossil fuel and motor vehicle, was the main sources of PAHs emission in Tehran.
M Banar, Ar Mesdaghinia, K Naddafi, Ms Hassanvand,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Radon is a radioactive, odorless gas. Radon gas with the emission of alpha radiation and sticking to aerosols in the air can cause lung cancer. This study evaluated the concentration of radon in residential houses and public places in Firuzkuh city and compared the values with the recommended international guidelines.
Materials and Methods: Radon gas concentration was measured by passive measurements using CR-39 detectors. The detectors were placed in houses and schools of the city for three months. After this time, the detectors were located and placed in a 6.25% normal solution at 85 °C for 4 hours in a laboratory. After preparation, using an automatic scan and appropriate statistical method, the concentration of radon gas was determined.
Results: The results indicated that the average concentrations of radon gas in homes and public places were 137.74 and 110.17 Bq/m3, respectively. Comparing the results with the WHO guideline showed that 76.3% of the homes and 66.7% of the sites had a concentration above the guideline (100 Bq/m3).
Conclusion: The results of this study can be used to prepare the National Radon gas map in the country.
H Hassanvand, N Dehghan, K Naddafi, Ms Hassanvand, R Nabizadeh, S Faridi, Z Yousefi,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Radon gas is one of the environmental risk factors which can increase the risk of lung cancer and it is well known as the second-leading cause of lung cancer after smoking. The aim of the present study was to investigate indoor radon gas concentration in residential and public environments of Nourabad Mammasani city and to estimate the effective dose due to radon exposure.
Materials and Methods: In this study, 52 homes and 8 public places were investigated to measure the concentration of indoor radon gas. Indoor radon concentrations were measured using passive sampling approach, alpha-track detectors (CR-39) for three months, and after that, detectors were sent to the laboratory to count the number of tracks.
Results: The results of this research showed that the average radon concentration (± SD) in the homes and public places was 42.4(±14.7) and 32.9(±20.1) Bq/m3, respectively. All radon concentration values were lower than the US Environmental Protection Agency standard and WHO guideline. The average of annual effective dose due to the radon exposure in homes was estimated to be 1.07 mSv. The evaluation of the results showed that there was a significant relationship between the room type and the number of floors with radon concentration in the residential buildings.
Conclusion: The results indicated that the indoor radon concentration as an environmental risk factor in the studied places was lower than the WHO guideline levels. Consequently, the indoor radon is not likely a major environmental risk factor in the studied environments.
K Naddafi, Ms Hassanvand, S Faridi,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Air pollution is a leading environmental risk factor on health and it is the major cause of death and disease at global level. Air pollution has been shown to have a significant share in the non-communicable diseases (NCDs) burden. After smoking, it is the second cause of deaths due to NCDs, associated with an increased risk of developing acute and chronic diseases and mortality.
Materials and Methods: In this study, a review was initially conducted on the basis of indices conducted in the world, the status of ambient air pollution and its effects on health in Iran and other countries, and then the status of ambient air quality and its effects on health in Tehran metropolitan between 2006 and 2017 were shown, based on the results of the studies conducted by the Environmental Research Institute of Tehran University of Medical Sciences.
Results: The results showed that the annual mean of ambient air population-weighted PM2.5 exposure concentration in Iran was about 48 μg/m3, which is relatively lower than its global mean concentration (51 μg/m3). Based on the most recent study (in 2018) about 8.9 (7.5-10.3) million deaths in those aged above 25 years were attributed to exposure to outdoor air PM2.5 in the world. Although there are substantial differences between the results of studies have been done regarding the number of air pollution attributed deaths, numerous studies showed that air pollution is a major cause of death. Results regarding temporal variations of air quality in Tehran that is performed by the Institute for Environmental Research (IER) of Tehran University of Medical Sciences (TUMS), indicated that PM concentration had an increasing trend from 2006 to 2011. The maximum mean concentration of PM2.5 over the past 12 years has occurred in 2011, which was 38 μg/m3. The PM concentration had a decreasing trend from 2012 to 2015, reaching about 30 μg/m3. However, in the years 2016 and 2017, the annual mean PM2.5 concentration in Tehran was increased compared to its corresponding value in 2015. Furthermore, results of this study demonstrated that, in Tehran, not even one day was classified as "good” (AQI=0-50) from 2011 to 2017 based on the air quality index (AQI), but the number of days in which AQI was “moderate” (AQI=51-100) was increased from 2011 to 2015, and the number of days with the AQI of “moderate” reached 80 in 2015, while the rest of the days having an unhealthy air quality. In 2017, AQI was “moderate” in 20 days, “unhealthy for sensitive groups” in 237 days, “unhealthy” in 107 days, and "very unhealthy” in 1 day. The obtained results indicated that about 4878 (3238, 6359( of deaths due to all (natural) causes were attributable to long-term exposure to PM2.5 in Tehran in 2017.
Conclusion: Studies showed that air pollution has a considerable share in the number of attributed deaths. Moreover, there were substantial differences between the results of national and international studies in the burden of disease attributed to air pollution. Therefore, there is a crucial need for accessing to reliable data on air pollution as well as baseline mortality and morbidity in order to study the status of air quality and its effects on health over the country.
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.
Mansour Shamsipour, Homa Kashani, Masud Yunesian, Kazem Naddafi, Mohammad Sadegh Hassanvand, Reza Saeedi, Mahdi Hadi, Alireza Mesdaghinia,
Volume 13, Issue 2 (8-2020)
Abstract
Background and Objective: In this study, we aimed to assess Iran’s position and trends for environmental health status among the countries of “Iran’s perspective document in 1404” according to the indicators used in Environmental Performance Index (EPI) report in 2018.
Materials and Methods: The score of indicators in environmental health area; air quality (including household solid fuels, exposure to PM2.5, and PM2.5 exceedance), water and sanitation (including drinking water and sanitation) and heavy metals (including lead) were extracted for all studied countries as well as for the last and baseline (generally ten years prior to last report) years from EPI 2018 database. According to EPI scores, the performance of the studied countries in each indicator was ranked. The percent change in the score of each indicator from baseline to current year was calculated and compared with the mean percent change for all studied countries.
Results: Iran ranked 7th regarding air quality in 2016. Also, it ranked 6th, 8th, and 9th in terms of household solid fuels, exposure to PM2.5, and PM2.5 exceedance, respectively. The EPI score for Iran regarding water and sanitation was 54.4 in 2005 and 58.74 in 2016 (percent change=7.98%). Iran ranked 21st in 2005 regarding lead exposure index. Although this index showed a growth of 100% in 2016, which is very desirable compared to the average growth of all countries (34.47%), but only leads to one step up in the ranking of Iran and was ranked 20th in comparison with other countries.
Conclusion: Totally, according to EPI 2018, Iran ranked 6th in the field of environmental health issues among 23 countries of “Iran’s perspective document in 1404”. However, there is uncertainty in the accuracy of the EPI raw data used for calculating index scores. Hence, caution should be exercised in their interpretation.
