Iranian Journal of

Backgrounds and Objectives : Heavy metals in dust can enter to the human body through ingestion andinhalation. They can pollute the water and soil resources via atmospheric precipitation and accumulate in the plants tissue and enter human body by water and food. The aim of this study was measurement of the heavy metals in wet and dry atmospheric precipitation and effects of pollution sources at the ground surface on the concentration of heavy metals in the atmospheric precipitations.
Materials and Methods: In this study the zanjan city was divided into 5 zones and wet and dry precipitations were collected in autumn, winter and spring (2008- 2009) from zones. The concentrations of Pb, Cd, Cr and Zn the collected precipitations were determined by Atomic Absorption spectroscopy method.
Results: The averages of concentrations of Pb, Cd, Cr and Zn were 0.082, 0.286, 0.018, and 0.009 (mg/m 2.d)respectively. The correlation coefficients between Pb-Zn was 0.8 (P<0.01) and for Cr-Cd, Cd-Pb, and Cr-Pb were 0.89, 0.58 and 0.61 respectively.
Conclusion: The results showed that the industrial sources of heavy metals play the main role in concentration of heavy metals in wet and dry atmospheric precipitation in Zanjan.The correlation coefficients showed that the lead and zinc result from a common source. This source can be the lead and zinc factories locating around the city. The measurement of heavy metals in atmospheric precipitation shows the effects of anthropogenic sources in air quality. The heavy metals concentration in atmospheric precipitation can be use as air pollution index.

Bachgrounds and Objectives: Oil, gas and petrochemical are known as important sources of air pollutants and emission of green house gases. About 99 percent of sulfur dioxide in the air is produced from human resources. Although several samples have been taken from industries and refineries' output by environmental experts and private companies, but accurate assessment is not available based on pollutant emissions on product levels (emission coefficients) and on the total amount of the annual emission which, can be used as basic modeling of air pollution and planning.
Materials and Methods: This study was cross sectional and the output of the chimney measured with Testo 350 XL system. Performance standard was determined based on ASTM D6522 EPACTMO30-41. The amounts of sulfur dioxide were measured from Tehran oil refinery's outlet from the beginning of the march 2007 till the year 2008 for 20 months. Sampling was carried out on averaged range (9 am to 14 pm).
Results: The results showed that Northern Distillation unit produced pollutants' concentration more than 3 times in the southern Distillation unit. An emission of pollutants from Northern unit was, 2.8 times higher than the Southern unit. The northern emission factor was 5.6 times higher than the value obtained from southern unit. The Concentration, emissions and coefficient of sulfur dioxide in North catalyst convert unit were more than 2 times in comparison with the same South unit. These three factors in northern concentration breakers unit were 3, 2.6 and 2.6 times higher than the Southern concentration breakers unit‚ respectively.
Discussion: Emission rate in all northern units is 2 to 3 times more than similar southern units. The production volumes in northern units are higher than the southern units and the southern units designed properly to remove more pollutants .The use of new technologies in production processes and application of the latest scientific resources can play a major role on pollutants' reduction.

BackgroundsandObjectives: Environmental activitiesunknownprice and value caused establishing of some unique characteristics for mentioned commodities. One of these characteristics was existing gap between private and social cost and benefit. For assessing these activities different approaches include travel cost, willingness to pay and hedonic price had been suggested. According to Tehran's air pollution problem, in this study Hedonic approach had was used for the assessment of healthy air on Tehran's residential house price.
Materials and Method : Hedonic approach is one of the methods that are used for evolution environmental goods. In this method, each good's price is estimated as a functions of that good`s properties. To gather this study information 300 questionnaires has been collected by random sampling from different area of Tehran.
Result: Results revealed that activities in order to reduce air pollutions, in addition to environmental value have economical value form the point of view of consumers. Also, results show that willingness to pay of every Tehran's citizens for every square meter of house located in region with less pollution is between 1120 to 1350 thousands Rials.
Conclusion: According to the obtained results can be said that, clean air as an environmental good from the viewpoint of consumers has economic value that can be calculated this value using methods such as Hedonic.

Background and Objectives: Industrial processes are the major sources of environmental pollutants. Oil & gas processing are one of the industries which emitting several air pollution matters in to the atmosphere. The obtained results of CO₂ emission in one of the Gas Sweetening unit of Iranian south oil company based on the field and deskwork calculations is presented in this paper.
Materials and Methods: Fuel analysis method is the best method for CO₂ estimation from combustion sources. In this paper, CO₂ emission factor for gas sweetening plants is estimated based on this method.
Results: The obtained results showed that  total CO₂ emission in selected unit is about 922212/97 (kg/d) and CO₂ emissions for the separate parts of this unit are 579661/75, 12921/93 and 329629/29 for acid gas flare, gas flare and boilers respectively.
Conclusion: comparison between the separated parts of the studied units showed that emission of acid gas flare is higher than other sources (i.e about 63% of total CO₂ emission), and by using the EPA default CO₂ emission factors the CO₂ emitted 1/2 % lower than the actual emission in the mentioned unit.

Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives:Benzene, toluene and Xylenes (BTX) are organic pollutants, which are mainly associated with oil and its derivatives. BTX is environmental contaminants and considered harmful to human health. Application of surface absorbents such as zeolite is one of several methods for the removal of these compounds. In this study, BTX compounds' removal efficiencies were investigated and compared by using clinoptilolite type zeolite and zeolite with copper oxide nanoparticles.
Materials and Methods: In this study, the modified zeolite by hydrochloric acid in the grain size 1-2 mm and modified zeolite with nano particle of copper oxide were used.  Artificially- Contaminated Air flow was used continuously .To determine BTX concentrations, samplings were done by charcoal tube in current input and output. The concentrations of contaminants were determined by gas chromatography with FID detector.
Results: Removal efficiency of benzene, toluene, p-xylene, m-xylene and o-xylene by clinoptilolite were 78.3%, 62.1%, 32.2% 32.15% and 18.8%, respectively. For the clinoptilolite containing copper oxide nano particles efficiency were 25.42%, 35.65%, 36.33%, 33.24% and 29.39%, respectively. Average removal efficiency of BTX compounds observed when the zeolite without nanoparticles used (43.31%) was more than zeolite with nanoparticles (32%). The results showed that the concentration of CO₂ in the outlet air of the zeolite-containing nanoparticle (550 ppm) was more than the zeolite without nanoparticle (525 ppm).
Conclusion: Results showed that adding nanoparticles to the zeolite, although the removal efficiency of benzene and toluene can be reduced. The results showed that adding nanoparticles to the zeolite, although can be reduced removal efficiency of benzene and toluene, which may be due to occupying or blocking of the pollution absorption sites by the nanoparticles on the zeolite, but It cause promote more catalytic effect of zeolite in the decomposition process of contaminants by breaking the molecules of pollutants and their further degradation progress is done for conversion to carbon dioxide

Background and Objectives: Air pollution and its effects on human health had become a major concern of many healthcare centers decision makers. In this study, air pollution effect on variation of Glycosylated Hemoglobin A1C (HbA1C) level in diabetic patients was evaluated, which is a unique study in Iran and Middle East region.
Materials and Methods: During November-January 2010-11, Tehran, capital of Iran, was exposed with high levels of air pollution. A retrospective cohort study was carried out on 330 patients diagnosed with diabetes mellitus for at least 12 months referring to 3 endocrinal care clinics. A questionnaire in two demographic and diabetic related sections was prepared. The patients' HbA1C level recorded on November-January 2009-10 was compared with November-January 2010-11. Descriptive analysis and paired t-test were carried out using SPSS 18 software.
Results: The patients investigated were divided into two groups. The first group was composed of 108 patients (53.7% female and 46.3% male) with diabetes mellitus type I (Insulin Dependent), age mean of 17.22, and SD of 11.57. The second group was composed of 222 patients (58.6% female and 41.4% male) with diabetes mellitus type II (Noninsulin Dependent), age mean of 53.91, and SD of 12.12. The change of HbAIC level in both groups wa not statistically significant in first group, HbA1C level increased from 7.71 to 7.75 mg / 100 ml (P =0.828) and in second group, it increased from 7.06 to 7.08 mg / 100 ml (P = 0.798).
Conclusion: According to the results obtained, it can be concluded that relation of air pollution and HbA1C mean variation in diabetic patients was insignificant.

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/PM_2.5 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 PM_2.5 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.

Background and Objectives: Exceeding the standard level in most cases, Tehran air pollution has become a national environmental challenge. Therefore, it is crucial to analyze Tehran air-pollution data set during 2000-2009 for trend analysis.
Materials and Methods: In this study, we collected the hourly data of Tehran air pollution during 2000-2009 recorded by monitoring station of Tehran Air Pollution Control Company and statistical methods was used to determine the trend of the five pollutants, including: CO, PM10, SO2, NO2 and O3.
Results: The results indicate that average annual concentration of PM10, CO, NO₂, SO₂ and O₃ has changed from 91, 11.18, 102.6, 46.8, and 22.1 at monitoring station in 2000 to 88 µg/m3, 3.64 ppm, 66.1 ppb, 21.4 ppb, and 83 ppb in 2009 respectively.
Conclusion: Our findings revealed that although the air quality in Tehran has improved in term of particulate matter, SO2 and NO2 during this decade as a result of government's recent program in air pollution control, ozone concentration has increased.

Background and Objectives: Transmission of pathogenic micro-organisms through the air is very dangerous for the society health. It is one of the most important issues that currently has faced the majority of hospitals with increasing nosocomial infections. Bio-aerosols are linked with a wide range of health effects including communicable diseases, acute toxic effects, and allergies and nosocomial infections, which can threaten health of personals, patients, and their companions admitted in hospitals. . Given that hospital infection rates has a direct relationship with the density and type of bioaerosols,, therefore, the distribution and abundance of micro-organisms, which wasthe main objective of the study becomes important. Materials and Methodes: This was a descriptive-analytic study in which seven wards of Valiasr hospital were selected randomly. The wards selected were Internal, laboratory, infants and children, CCU, Men surgery, women and labors. Operating rooms and outside the hospital environment were also studied. Air samples were taken according to the NIOSH standard instructions and Anderson procedure with a flow rate of 3.28 L per 2 minutes on mannitol salt agar, nutrient agar, EMB agar, blood agar, and sabarose dextrose agar media. Out of 240 samples taken, 200 samples showed growth. Then, the samples were transported to laboratory immediately and were incubated for 48 h at 37˚C and the experiment temperature was 22-27˚C, and afterwards each sample was counted andtested. At the end, the microorganisms density was determined in term of CFU/M3. Results: The highest average concentration of pollution occurred in Infectious Ward (238.51 CFU/ M3 in spring and 167.02 CFU/M3 in autumn) and the lowest one was related to the CCU, where showed no fungi growth during both seasons. Despite the environment sterilization, the highest percentage of fungi (Aspergillus Niger) and yeast observed in the hospital air was 42.45 percent in spring and 44.26 percent in autumn respectively. Moreover, Staphillus Epidermithis (25.93 percent)and gram-positive bacillus were the highest percentage of bacteria identified in air samples. Conclusion: From the findings of this study, it can be concluded that the concentration of bio-aerosols in different hospital wards expect in CCU was more than recommended and similar studies and in terms of species was similar to other studies. Therefore, the hospital authority is recommended to reduce the amount of the pathogenic and environmental bio-aerosols through controlling individual traffic, changing the disinfectants and their applying procedure on the wards surface, establishing standard and suitable ventilation systems.

Background & Objectives: Determining the impacts of air pollution in cities is facing two major challenges first, the limited data on the health effects of pollutants, and secondly, the lack of information on exposure to air pollutants and their concentration. This is an applied-observational carried out to determine the concentration, seasonal changes, and to estimate the health impacts attributed to the particulate matters in Tabriz during September 2012 to July 2013. Materials and Methods: The particulate matters were sampled using high volume sampler and were analyzed using portable HAZ-DUST EPAM-5000. The health impacts of particulate matterswere estimated using AirQ software developed by W.H.O. Results: The annual mean concentration of TSP, PM₁₀, PM_2.5, and PM₁ in the urban sampling site were 139, 83, 38, and 27 µg/m³ respectively. In addition, these concentrations were 178, 110, 40, and 27µg/m³ in industrial area. The average of PM₁₀/TSP, PM_2.5/PM₁₀, PM₁/PM₁₀, and PM₁/PM_2.5 ratio level was 0.6, 0.48, 0.33, and 0.7 in the urban areas and 0.61, 0.37, 0.28, and 0.77 in the industrial areas respectively. The total mortalities associated with the TSP, PM₁₀, and PM_2.5 concentrations were estimated as 327, 363, and 360 respectively. Nevertheless, the calculated cardiovascular mortality for TSP and PM₁₀ were estimated to be 202 and 227 respectively. Conclusion: This research found that the concentrations of PM₁₀ and PM_2.5 were 73 and 69% more than National Standard and 8 and 5% more than USEPA Standards respectively. In Tabriz, especially industrial area, the soils of surrounding ground and re-suspension of particles fromcontaminated soils have a significant contribution to particulate emissions.

Background and Objective: Increasing air pollution and consequently adversely effects on the quality of life for many people has resulted in the use of the air quality indice for determination of the actual amount of pollutants and air quality, as one of the most important and effective measures for air quality control, to be considered further. The air quality health index (AQHI) is a new index related to air pollution developed in collaboration with Environment Canada and Health Canada, in 2001. The purpose of this study was to design and develop a software system for calculating AQHI for the first time in the country that calculates the health effects caused by the presence of several pollutants (NO_2, O_3,PM_10, and PM_2.5) at the same time with a new approach.

Materials and Methods: To achieve those aims, the software was designed and coded in Visual Basic. Net. After preparation of the software, it was tested using the real-time database of  six air pollution monitoring stations in Tehran including Aghdasyeh, Setad Bohran, Shahrdari 4, Golbarg, Park-e- Roz, and Shahrdari 11.

Results: This program is a software package installed on the computer with the possibility of exporting Excel file. The performance of software testing was verified using real data.

Conclusion: The results of the verification tests show that the index calculated by the software introduced and presented in this study can be used as a useful tool to assess air quality.

Background and Objective: The present study was carried out to determine the amount and ionic characterization of TSP and PM₁₀ aimed at identifying  the potential emission sources of particulates in the ambient air of Tabriz.

Materials and Methods: TSP and PM₁₀ samples were collected by two high volume samplers during September 2013 to August 2014. Water-soluble ions in particulate matter were extracted using ultrasonic method and were identified by ion chromatography. Using Stata12 software, linear regression analysis was performed between the ions to determination of the major ionic component of the particulates. In addition, in order to identify the potential emission sources of PM₁₀, the rotation varimax model was used.

Results: Total measured water-soluble ions in TSP and PM₁₀ of the urban sampling site were 20.33±20.77 and 16.04±14.08 µg/m³, respectively. Among all detected ions, sulfate (8.69±5.79 µg/m³) and nitrate (8.47±7.9 µg/m³) were the dominant constituents followed by calcium and sodium.

Conclusion: The modeling results revealed that the soils of surrounding ground together with secondary PM and also resuspension of PM from polluted soil account for 80 percent of PM₁₀ mass.

Background and Objective: The aim of present study was to assess environmental inequality in long-term exposure to outdoor air pollution in 22 districts of Tehran in 2012.

Materials and Methods: The present study is an ecological study and concentration index was used for assessment of inequality. In this study the amounts of pollutant concentrations (PM₁₀, NO₂, SO₂) obtained were based on land use regression (LUR) for exposure assessment. Variables that their effects have been studied on the distribution of exposure to pollutants included: education level, employment status and car ownership, which were obtained from census demographic and Tehran Municipality's dataset.

Results: The concentration index for PM₁₀ in the case of illiteracy, people with higher education and private car owners was 0.059 (0.004-0.113), -0.056 (-0.001- -0.110) and -0.079 (-0.031- -0.127), respectively. These relationships were statistically significant. Concentration index for PM₁₀ was 0.016 for the workers population, which was not statistically significant. For NO₂ and SO₂, no inequality was found in illiterate people, people with higher education, employees and car owners.

Conclusion: This study showed that there was significant inequality in terms of exposure to PM₁₀ between different regions of Tehran in the illiterate, people with higher education and car owners. Considering these subgroups of population can be helpful in policy-making process.

Background and Objective: During the past few decades, air pollution has been the focus of international attention due to an increase in deaths from air pollution. In this study, Volatile Organic Hydrocarbons (VOCs) and Total Hydrocarbons (THCs) in ambient air of a Petrochemical Complex, Iran, was measured. Also, the relationship between these pollutants and some of their urinary metabolites was evaluated in the petrochemical complex workers.

Materials and Methods: These pollutants were measured in two stages, in spring (40 samples) and summer (40 samples), in ambient air of the different units of the complex. Urinary metabolites were measured in accordance with the NIOSH standard method using a GC-FID and TD/GC-MS.

Results: Total average of THCs in the spring and summer was 14.06 and 15.85 ppm, respectively; this amount was 14.09 and 16 ppm for VOCs. In summer, the highest values of VOCs (48.19 ppm) and THCs (47.63 ppm) were measured in Recovery unit. Total average of the urinary metabolites including Phenol, Phenylglyoxylic acid (PGA) and Mandelic Acid (MA) was 16.67, 34.8, and 67.24 mg/g creatinine respectively; in spring, it was 15.34, 57.34, 30.5 mg/g creatinine respectively

Conclusion: Background variables such as age, weight, and smoking habit had different impacts on the level of metabolites. The values of measured pollutants were lower than the guideline values proposed by the American Association of Industrial Hygienists (ACGIH). In addition, the values of measured metabolites in urine were less than the biological exposure index (BEI) provided by ACGIH.

Background and Objective: Concentration prediction with Gaussian dispersion models is highly sensitive to meteorological data. The lack of sounding data station in developing countries may lead to large error and uncertainty in air pollution modeling results. In this paper, the effects of estimated upper air data on the model output concentration values were investigated.

Materials and Methods: AERMOD model was executed once with real upper air data and also with estimated upper air data separately. T-Student and LEVENE tests were used to evaluate the significant differences between concentrations in two modes of using actual and estimated upper air data.