Iranian Journal of

---

Background and Objectives: Heavy metals processing industry has always been a major cause of concern which affects soils, surface waters, ground waters and river sediments contaminations. Thus, the Zanjan Zinc and Lead Smelting Plant has been considered as a potential source of contamination.
Mterials and Methods: This cross-sectional study has been conducted in February 2008 in the site region .The concentrations of Lead, Zinc and Cadmium have been assessed. The samples have been taken from 17 wells and atomic absorption spectrophotometeric method has been used to assess the samples. In order to find out and locate the exact situation of the wells under study, Global Positioning System instrument has been used. The correlation between the concentration of each metal and the distance of studied well from the plant has been assessed too.
Results: The findings of this study showed that lead and cadmium concentrations were 53% and 59% respectively out of the guideline values of World Health Organization.
Conclusion: The concentration of Zinc was lower than both national and international values in all samples. As the heavy metal concentration is very important for human health status, the other fields of study like heavy metal air pollution effects and related diseases and conditions should be studied and assessed.

---

Backgrounds and Objectives: Noise in large cities is considered by the World Health Organization to be the third most hazardous type of pollution. Buses are an interesting object of study in the theme of noise pollution. They are at the same time a source of urban environmental (traffic) noise and occupational noise exposure source for drivers. The object of this study is Occupational noise exposure evaluation in drivers of bus transportation of Tehran city.
Materials and Methods: Noise levels in 90 buses were sampled in three separate sub-sample including (1)30 Ikaroos buses (2)30 Man buses (3)30 Shahab buses, which were selected by simple random sampling. Noise exposure level was normalized to a nominal 8-h working day (LEX, 8h). Simultaneous Octave Frequency Analysis were measured and sound intensity level (SIL) for bus drivers were calculated. Results, which are obtained from separate buses were compared together and too with standard levels.
Results: the normalized noise exposure levels (LEX, 8h) in Ikaroos bus drivers(82dB A) were higher than that of in in Man bus drivers (77/6dB A) and this Values were higher than that of in Shahab bus drivers(75dB A).SIL values for Ikaroos bus drivers were higher than other that of other bus drivers. Results obtained of Frequency Analysis showed that age of buses in mid frequencies ws a meaningful on noise increase.
Conclusion: Results showed that type and age of buses were effective factors in drivers. noise exposure levels (LEX, 8h), which was consistent with previous studies in this field.

---

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.

---

Backgrounds and Objectives: Shortage of available water resource and deficiency of rainfall, increasing in population growth and industrial development, suitable use of water resources and pollution prevention is an essential issue in accord with sustainable development and environmental protection. Present study shows the qualitative status ofMehran River and determines its pollution or non pollution tomunicipal wastewater and to assess qualitative characteristics of the water according to international water quality index.
Materials and Methods:Padding strand of MEHRAN River from source to end has been done for wistful determination of branches, runoff and wastewater entrances, etc. Necessary decisions were made for determining sampling points and critical and effective points on water quality then water samples were analyzed to determine chemical and microbiological characteristics.
Results: Results showed the average of BOD5, COD, TSS, NO3, DO, pH, Turbidity and color are about 80±30, 155±58, 1013±637, 7.3±2, 4.5±3.5 mg/l, 7.2 ±1, 385±238 NTU, 122±70 TCU respectively.
Conclusion: It could be concluded that the Mehran River is completely polluted with municipal sewage and is unsanitary.Water quality index varies in the range of 41-52 and the water is classified as number 4. At present the river is in a dangerous ore toxic state and could not be considered as drinking water resource or needs more advanced water treatment units.

---

Background and Objectives:Anzali Wetland is one of the most important aquatic ecosystems of Iran which is located in south-west of the Caspian sea. This Wetland provides a suitable and non-market price habitat for valuable fish and aquatic animals which have an important role in the life cycle of this ecosystem. This study reports the results of some heavy metals contamination monitoring in superficial water of the Anzali Wetland, Iran.
Materials and Methods: The samples were collected from three sites (east, center and west) of Anzali Wetland, in each site three stations existed and each sample replicated three times.
Results: The results showed high heavy metal levels in eastern site of wetland, where there were high levels of contamination. The mean of heavy metals concentration in sediment from Anzali Wetland were in order as Cd 157.023, Pb 3.646 and Hg 300.692 ng /g dried weight, Zn 186.953 and Cu 44.452 mg /g dried weight in eastern site. The concentration levels of heavy metals in three sites were in order as follows: Zn > Cu > Hg > Cd > Pb.
Conclusion: Concentrations of heavy metals in eastern zone reflected metal loadings from anthropogenic sources located at and in the vicinity of the sampling sites.

---

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

---

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/m², 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.              

---

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: Weather pollution, caused by Ozone (O3) in metropolitans, is one of the major components of pollutants, which damage the environment and hurt all living organisms. Therefore, this study attempts to provide a model for the estimation of O3 concentration in Tabriz at two pollution monitoring stations: Abresan and Rastekuche.
Materials and Methods: In this research, Artificial neural networks (ANNs) were used to consider the impact of the meteorological and weather pollution parameters upon O3 concentration, and weight matrix of ANNs with Garson equation were used for sensitivity analysis of the input parameters to ANNs.
 Results: The results indicate that the O3 concentration is simultaneously affected by the meteorological and the weather pollution parameters. Among the meteorological parameters used by ANNs, maximum temperature and among the air pollution parameters, carbon monoxide had the maximum effect.
Conclusion: The results are representative of the acceptable performance of ANNs to predict O3 concentration. In addition, the parameters used in the modeling process could assess variations of the ozone concentration at the investigated stations.

---

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 and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater. Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1) with fertilizer and effluent (W2). Results: At the end of growth season, soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis, total number of positive lactose bacteria, total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves, total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover, for new leaves, it was 38 and 2 MPN/100 ml respectively. Conclusion: According the results, number of indicator bacteria in soil is decreased (about 35%) by passing time.

---

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.

---

Background and Objectives: Due to the importance of Sanandaj Gheshlagh Reservoir (SGR) in the region and proven mercury pollution in SGR water, a research project was carried out to determine the amount of mercury concentration and bioaccumulation and its behavior through a food route in SGR food chain (i.e., water, sediments, fish, and human).This was done, because it has been reported that mercury concentration and its toxicity could increase during mercury exchange between trophic levels. Materials and methods: During April to December 2012, 24 water, sediment, and fish samples (Capoetta trutta) (4 samples per month) from SGR and 24 human hair samples from Sarab Ghamish village settlers (the major Capoetta trutta consumers in the region) were collected. Results: Total mercury mean concentration in water, sediment, Capoeta trutta, and human hair were 0.0028±0.000128, 0.110±0.0057, 0.296±0.0119, 2.059±0.1704 ppm respectively. Calculated bioconcentration factors were 4 × 10 and 1 × 10² in SGR sediment and fish, and related biomagnifications factors were 40 and 5 respectively. Conclusion: Due to the high bioaccumulation, biomagnifications factors and mercury concentration recorded in edible parts of SGR fish, local consumers should not eat more than 1182 gram of this fish weekly without accounting for other potential sources of total mercury in their food basket.

---

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 Objectives: Over the past few decades, the entry of pollutants, especially PAHs compounds in natural ecosystems such as lakes and open water for aquatic organisms has created potential environmental hazards. This study aimed to investigate the extent and pattern of bioaccumulation of pyrene oil pollution in muscle, gill, and liver of common carp (Cyprinus carpio) cultured in vitro. Materials and Methods: thirty fishes with mean weight of 140±10g were exposed to 10, 50, and 100 µg/l pyrene. At the end of the 35 days trial period, fish were sampled in order to study the pyrene accumulation in different tissues. Preparing process of samples include soaping, extracting, and two-phase chromatography and finally injecting samples to the gas chromatography-mass spectrometry. Results: Comparison between bioaccumulation of pyrene in muscle, gill, and liver tissues of cyprinus carpio in 10, 50, and 100 µg/l doses showed significant differences. Maximum average accumulation was in liver (dose100) with 685.67 ± 78.5 and the minimum was in muscle in dose 10 with 0.52 ±. 0.13 pyrene’s accumulation trend was the same in all studied doses: liver>gill>muscle. Conclusion: In the present study, pyrene accumulated in fatty tissue, especially liver-acceptor of all of the oil pollutants- was far more than of gills and muscle.