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Showing 7 results for Pahs
Comparison of Nutrients and Salinity on Phenanthrene Removal from Polluted Soil 
Maasoumeh Ravanipour, Roshanak Rezaei Kalantary, Mahdi Farzadkia, Samireh Hashemi-Najafabadi, Ali Esrafily,
Volume 5, Issue 4 (2-2013)
Abstract
MicrosoftInternetExplorer4 Background and Objectives:The poor accessibility of microorganisms to PAHs in soil has limited success in the process of bioremediation as an effective method for removing pollutants from soils. Different physicochemical factors are effective on the rate of biodegradation. The main objective of this study is to assess effects of nutrient and salinity on phenanthrene removal from polluted soils.
Materials and Methods:The soil having no organic and microbial pollution was first artificially polluted with phenanthrene then nutrients and salinity solution in two concentrations were added to it in order to have the proportion of 10% w:v (soil: water). After that a microbial mixture enable to degrade phenanthrene was added to the slurry and was aerated. Finally, the residual concentration of Phenanthrene in the soil was extracted by ultrasonic and was analyzed using GC. We measured the microbial populationusing MPN test. This study was conducted based on the two level full factorial design of experiment.
Results: MPN test showed that the trend of microbial growth has experienced a lag growth. The full factorial design indicated that nutrient had the maximum effect on bioremediation the rate of phenanthrene removal in the maximum nutrients - minimum salinity solution was 75.14%.
Conclusion: This study revealed that the more nutrient concentration increases, the more degradation will be happened by microorganisms in the soils. However, salinity in the concentration used had no effect on inhabitation or promoting on the Phenanthrene removal.


Ecological Risk Assessment of Polycyclic Aromatic Componds in the Surface Sediments of Anzali Wetland in 2010
Rokhsareh Azimi Yancheshmeh, Ali Reza Riyahi Bakhtiari, Samar Mortazavi,
Volume 7, Issue 2 (10-2014)
Abstract

Background & Objectives: In recent years, enterance of oil contaminants especially polycyclic aromatic hydrocarbons (PAHs) to Anzali Wetland, has seriously threatened organisms life. Therefore, the current study was conducted to determine and compare concentration of PAH compounds with multiple sediment quality assessment indice to evaluate the ecological toxicity of surface sediments of Anzali Wetland and present appropriate management strategy. Materials & Methods: We randomly collected 22 surface sediment samples each sample was dried and extracted based on the soxhlet method. Then during two-step of column chromatography the PAH compounds were separated and analyzed by gas chromatography equipped with a mass spectrometry detector (GC-MS). Results: Total concentrations of these compounds ranged from 212 to 2674 ng g-1 d.w. with the mean of 907 ng g-1 d.w. The highest concentrations of PAHs was reported from stations (3-1 and 4-1) located in the vicinity of urban areas with shipping activities. In comparison with sediment quality guidelines (SQGs) used in this study, the concentrations of most PAH compounds in the majority of stations situated in low range values of adverse biological effects. Only in a few stations (3-1, 3-2 and 5-3), the concentrations of some of PAH compounds exceeded the low range of adverse biological effects. Conclusion: In comparison with sediment quality guidelines (SQGs) used in this study, the concentrations of most PAH compounds in Anzali Wetland rarely lead to adverse biological effects. However, concentrations of some of these compounds can cause acute toxic effects. Therefore, further studies including toxicity and bioaccumulation tests and survey of benthic community composition, especially in areas exceeded SQGs are essential for proper management.


Distribution and Source identification of Polycyclic Aromatic Hydrocarbons (PAHs) in the Sediments of the Southwest Caspian Sea Coasts: Gillan Province
M. Nemati Varnosfaderany, A. Riyahi Bbakhtiari, Z. Gu, G. Chu,
Volume 7, Issue 3 (5-2014)
Abstract

Background and Objectives: Few investigations on polycyclic aromatic hydrocarbons (PAHs) in surface sediments have reported medium to high petrogenic contamination at the southwest coasts of the Caspian Sea. The aim of this study was to investigate distribution and potential sources of 16 PAH compounds in surface sediments of the southwest coasts of the Caspian Sea (Gillan province). Materials and methods: A total of 45 sediment samples from 15 stations at coasts of the Gillan province (from Astara to Lahijan) were collected from 10, 20, and 50 meters depths. Each sample was analyzed using Gas chromatography – Mass spectrometry. Diagnostic ratios were used for source identification. Results: The main PAH compounds in the study area were phenanthrene (87.6±74.6 ng/g), pyrene (43.1±23.5 ng/g), and naphthalene (34.4±40.4 ng/g) respectively. According to the calculated diagnostic ratios such as LMW/HMW (0.25-7.75), Ant/178 (0.02-0.11), Flu/202 (0.20-0.49), and B(a)Ant/228 (0.09-0.54) the main source of PAHs is petrogenic in this study area. Conclusion: According to PAH diagnostic ratios and similarity of dominant PAH compounds in study area with dominant PAH compounds of Azerbaijan oil field, main probable source of PAH compounds in Gillan province coasts is Azerbaijan oil pollution.


Assessing effects of seasonal variation on occupational exposure of newsagent kiosks to polycyclic aromatic hydrocarbons found in the urban atmosphere of Tehran Metropolitan
F Rezaei, H Kakooei, R Ahmadkhaniha, K Azam, L Omidi, S.j. Shahtaheri,
Volume 8, Issue 2 (8-2015)
Abstract

Background and Objectives: PAHs are main components of urban air pollution and are mutagenic for human being. Seasonal variations have effects on the amount of exposure to PAHs. The objectives of this research were to determine the amount of newsagent’s exposure to PAHs found in the urban atmosphere of Tehran City during warm and cold periods and comparing exposure levels in two periods. Materials and Methods: The assessment of personal exposure was performed based on NIOSH method 5515 and was analyzed by gas chromatography–mass spectrometry (GC/MS). Mann- Whitney test was used to determine the effects of seasonal variation on the amount of newsagent’s exposure to PAHs. Results: The mean levels of newsagent’s exposure to benzo[a]pyrene in the south area of Tehran City were 0.148±0.010 and 0.417±0.041 µg/m3 in summer and autumn seasons respectively. The amount was higher than the mean levels of newsagent’s exposure in other geographic areas of city. The levels of newsagent’s exposure to all PAHs (p<0.001) were significantly higher in autumn compared with summer. Conclusion: The levels of exposure to PAHs during autumn were 2 to 3 fold higher than the levels of exposure during summer. Newsagents in the south area of Tehran City were experiencing higher levels of exposures to PAHs.


Determination of polycyclic aromatic hydrocarbons in water using an electrochemical DNA biosensor
R Manaffar, B Sehatnia, R Sabzi, A Ehsani,
Volume 8, Issue 2 (8-2015)
Abstract

Background and Objectives: Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental contaminants in aquatic environments. These contaminants are generated through oil spills, manufactory processes, and industrial wastes or naturally through the incomplete combustion of coal, oil, gas, and wood waste. Most of these compounds are noted as carcinogenic and mutagenic. Therefore, detection of these pollutants by a sensitive and inexpensive method is very important. Materials and Methods: In this study, an electrochemical DNA biosensor was used to detect PAHs due to its sensitivity, ability, and high response rate. For this purpose, the bovine thymus double-stranded DNA was fixed on a screen-printed electrode. Then, the electrodes electrochemical behavior was investigated. This electrochemical DNA biosensor works upon the difference between the electrochemical response of guanine bases in DNA structure in the presence and absence of PAH compounds. To evaluate the biosensors performance, the response of biosensor to real samples was compared with conventional pollutant determination methods like liquid-liquid chromatography. Results: Optimum conditions were examined for biosensor response including effect of activation potential and time on electrode pretreatment, applied potential for DNA immobilization, and detection potential. Under optimal conditions, the pretreatment of the electrode obtained in 1.6 V for 350s, then the DNA was immobilized on the electrode surface by applying a potential of -0.5 V to detect different PAHs in real samples in the range of micro molar. Conclusion: Electrochemical DNA biosensors are capable of detecting the sum of PAHs in water samples with high accuracy, sensitivity, and low cost compared with chromatographic methods.


Source identification of PM10-bound Polycyclic Aromatic Hydrocarbons (PAHs) of Tehran ambient air in year 2013
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.


Concentration and source identification of polycyclic aromatic hydrocarbons in office building dust of Isfahan metropolitan, Iran
Qasim Jalal Smian, Soheil Sobhanardakani, Atefeh Chamani,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Nowadays, individuals spend a lot of time indoors; thus they are exposed to hazardous compounds including polycyclic aromatic hydrocarbons (PAHs) with teratogen, mutagen, and carcinogen potential. Therefore, this study was conducted to detect, and determine the content and source apportionment of PAHs in office building dust samples of Isfahan metropolis in 2023.
Materials and Methods: In this descriptive cross-sectional study, 84 indoor dust samples were collected from 28 sampling sites. After extraction of analytes, the gas chromatography/mass spectrometry (GC–MS) method was used to determine PAHs content in the samples. Molecular diagnostic ratios (MDRs) were used to determine the origin of PAH compounds. Furthermore, all statistical analyses were performed by SPSS software.
Results: The results showed that 16 priority PAHs were detected in the office building dust samples with the minimum, maximum, and mean values (µg/kg) of 4575, 16589, and 9838. Moreover, based on the results obtained, the mean contents of NAPH, FLU, PHE, FULA, PYR, BaA, CHR, BbF, BkF, BaP, DahA, BghiP, and IcdP species were higher than the maximum permissible concentration (MPC) established by Iran DOE. The results of the MDRs method indicated that although PAHs originated from both pyrogenic and petrogenic sources, the pyrogenic sources had the main role in the pollution of office building dusts with PAHs.
Conclusion: Due to risks arising from exposure to PAHs, detection, determination of contents, source identification, and especially health risk assessment of PAHs in indoor dust of other closed places such as commercial, educational, and recreational buildings as well as households is recommended.
 

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