Showing 9 results for Monitoring
Mehdi Ahmadi Moghadam, Parviz Mahmoudi,
Volume 6, Issue 1 (5-2013)
Abstract
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.
N Rastkari, F Izadpanah, M Yunesian,
Volume 8, Issue 2 (8-2015)
Abstract
Background and objective: Benzene is one of the main pollutants in air and one of the most extensive chemical compound used in both natural and industrial processes. Benzene exposure leads to the most dangerous adverse health effects, particularly blood cancer. The aim of this study was to evaluate the gas station workers’ exposure to benzene by measuring benzene in breathing air and urinary trans, trans-muconic acid. Materials and Methods: This cross-sectional study conducted in summer 2014 investigated 40 gas station workers and 40 occupationally non-exposed persons. Spot urine samples were obtained prior to and at the end of the work shift from each subject. The urinary levels of trans, trans-muconic acid was determined by liquid chromatography (HPLC) with diode array detector. At the end of the work shift, the benzene collected on sorbing cartridges was desorbed using carbon disulfide and was analyzed using gas chromatography and mass spectrometry detection. Results: The mean value for exposure to benzene in breathing zone of gas station workers was 5.90 ±1.93 ppm, which was significantly greater than the occupationally non exposed group (1.15±0.744 ppm). The mean urinary concentrations of trans, trans-muconic acid differed significantly between samples of gas station workers (64.75±19.47 µg/L) and occupationally non-exposed persons (47.10±13.67 µg/L). Conclusion: A good correlation (r = 0.581) between the mean values of benzene in breathing zone and the urinary concentration trans, trans-muconic acid was observed. Gas station workers were found to be probably the most exposed groups in this study. Inhalation is presumably the main route of exposure in gas station workers.
H Adab, A Atabati, R Esmaili, Gh Zolfaghari, M Ebrahimi,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Optimum number of air quality monitoring stations in Mashhad is an essential task for management of the urban environment. However, real monitoring and accurate information on the status of air quality require proper spatial distribution of air quality monitoring stations in the city of Mashhad. The aim of the present study was to determine optimum site locations for air quality monitoring, including Downtown Pedestrain Exposure Station, Downtown Background Exposure Station, and Residential Population Exposure Station by three Multiple-Criteria Decision-Making (MCDM) techniques.
Materials and Methods: In the precent study, sites for new air quality monitoring stations t in Mashhad were determined based on a proposed protocol in the United States. Accordingly, the criteria effective for site selection such as population density, distance from existing stations, vicinity to vegitation, vehicle density and other factors were used by applying Analytic Hierarchy Process (AHP), Fuzzy set, and Probability Density Function (PDF).
Results: Location similarity of the sites proposed by decision making methods was evaluated to know its reliability. The compactness of distribution of the proposed sites were compared by applying spatial statistic methods auch as Average Nearest Neighbor (ANN) and Standard. The results from ANN indicated that fuzzy set mapped the suggested sites was fully scattered within the entire city of Mashhad and was statistically significant at 99% confidence level. The PDF method also offered the same spatial pattern as fuzzy set. Overall results of this study indicated spatial optimization of suggested sites location for fuzzy set and PDF.
Conclusion: The overall results of the decision-making methods used in this study indicated that it is necessary to increase number of air quality monitoring stations at Northwest of Mashhad due to the urban growth in the city. The results also showd the possibility of using Probability Density Function (PDF) as a method of decision-making in GIS for locating and ranking of new air quality monitoring stations.
N Okati, A Esmaili-Sari,
Volume 10, Issue 2 (9-2017)
Abstract
Background and Objective: Information about the history of exposed individuals to mercury and monitoring mercury levels in body can be obtained by analyzing the longitudinal section of hair. The aim of this study was to analyze changes of mercury concentrations in hair length and daily mercury intake in women living in Bandar Abbas, Bushehr and Mahshahr cities.
Materials and Methods: In this cross-sectional and questionnaire study, 43 hair samples were randomly collected from women in fisher and non-fishermen families. Mercury concentrations were determined by LECO AMA 254, Advanced Mercury Analyzer (USA) according to ASTM standard NO.D-6722.
Results: The mean mercury concentration in hair was 2.31 μg/g. ANOVA test showed that there is no significant difference among the mercury concentrations in the various parts of hairs. The mean daily mercury intake was 0.24 μg/kg/day. Age, fish consumption, city of residence, fishermen and non-fishermen family had a statistically significant effect on the daily mercury intake in the women but the number of dental amalgam filling variable had no significant effect on the daily mercury intake.
Conclusion: During the 6 month period that the study was conducted, the methyl mercury uptake in the women was steady. The daily intake of mercury in 23% of the women was exceeded JECFA guidelines. Also, according to possible risks for mercury exposure, it is necessary to study on mercury risk assessment, considering all possible routes for mercury exposure in these cities.
M Bayatvarkeshi, R Fasihi,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Drought and water shortage in recent years caused rice farmers to use maximum groundwater as a secure source. However, the rice is affected not only by the quantity but also by the quality of water. The purpose of this study was to evaluate trend of quality parameters of groundwater in wet and dry periods in 4 plains including Astaneh, Talesh, Lahijan and Foumanat, which are all located in Gilan province.
Materials and Methods: In this investigation, data was collected for quality parameters from 15 groundwater of the 4 plains of Gilan province from 2003 to 2014. The data was collected from 15 piezometer wells of Astaneh, 41 piezometer wells in Talesh, 24 piezometer wells in Lahijan and 44 piezometer wells in Foumanat. For each well, two time series of 15 quality parameters in wet and dry periods were created in SPSS software. The trend was evaluated by Mann- Kendall test that is a nonparametric method.
Results: The results showed that in both periods, the trend of most quality parameters was declined, However, the quality decline in wet period was more severe. In both periods, the pH and Na % were increasing. Additionally, in dry period, the increasing trend of SAR and SO4 was observed. Overall, the water quality of wells in Talesh plain for cultivation of rice was better than the other plains.
Conclusion: Consumption of groundwater of all the plains in both wet and dry periods for agricultural purposes and especially rice cultivation was without limitation. According to the decreased concentration of the measured parameters during the studied period, it can be expected that groundwater quality of Gilan province plains has been improved.
H Abbaszadeh, M Mohammadi Roozbahani, S Sobhanardakani,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Environmental pollution emitted from industrial areas while enter the food chain can cause serious adverse health effects. Therefore, this study was conducted to use Ziziphus spina-christi and Prosopis cineraria leaves as bio-indicators of environmental pollution emitted from the complex of Steel Company.
Materials and Methods: In this descriptive study, a total of 90 surface soil samples and also 90 leave samples were collected. After acid digestion of samples, the heavy metal contents were measured using atomic absorption spectrophotometer. Also, the Bioconcentration Factor (BCF) of metals were computed. All statistical analyses were performed using SPSS statistical package.
Results: The highest content of the metals (mg/kg) with an average of 2180.3 ± 202.3 and 2237.9 ± 315.1 for Fe, 76.6 ± 9.6 and 114.3 ± 4.5 for Pb and 69.2 ± 16.8 and 107.2 ± 6.8 for Cd were found to be in Z. spina-christi and P. cineraria unwashed leaves respectively. Also, the BCF of all studied metals were higher than 1.
Conclusion: Based on the values of BCF, it can be concluded that Z. spina-christi and P. cineraria can be considered as a suitable species for phytoextraction of heavy metals in the most polluted regions including industrial and urban areas.
Mazaher Moeinaddini, Seyed Hassan Mousavi, Zohreh Isakhanbeygi, Somayeh Heidari,
Volume 13, Issue 3 (11-2020)
Abstract
Background and Objective: One of the most important goals for urban environmental management system is the monitoring of air quality. Allocating optimum air quality monitoring stations (AQMS), is a key factor in establishing effective and accurate air quality monitoring program. The objective of this study was to determine optimal allocation for AQMS in Karaj.
Materials and Methods: Based on two stages approach, at first, the suitability map was obtained by WLC method. For AQMS implementation, municipal districts were ranked. The extracted alternatives were graded using TOPSIS. In the next stage, the position of preferred sites were investigated by site visiting and detailed criteria. Finally, the AQMS locations were introduced.
Results: Ten suitable stations were suggested based on population and number of municipal districts. During the first stage important criteria such as distance from roads and street cross-section were weighted and standardized. The distance from roads and green space were the lowest and highest important criteria, respectively. The lowest and highest ranks for AQMS implementation were Nos. 9 and 3 districts, respectively. During the first phase 30 alternatives were obtained. At the second stage, 10 best alternatives were selected following field observation and considering implementation criteria (eg. distance from trees, cross section and pollutants emission sources).
Conclusion: In this study, at the first stage the preferred alternatives were determined. In the next stage the best alternatives for AQMS implementation were selected considering reasonable time and effort. The suggested approach could be used to implement AQMS for other areas.
Mohammad Sohrabi, Nasrin Hassanzadeh, Fariba Hedayatzadeh, Mehdi Mofid,
Volume 13, Issue 4 (2-2021)
Abstract
Background and Objective: Air quality and distribution of trace elements in the Tehran metropolis were evaluated using transplants of the epiphytic lichen Ramalina sinensis.
Materials and Methods: Thalli of R. sinensis were collected from a non-contaminated area and transplanted in the six urban sites of Tehran for six months. After the end of the exposure period, the content of twelve elements in lichen was determined by ICP-MS method and the obtained data were evalusted using statistical analysis and various indicators.
Results: Based on the results, the order of mean concentration of the trace elements in the R. sinensis lichen samples was determined as: Ca > K > Fe > Mg > Na > Mn > Zn > Pb > Cr > Cu > Ni > Co and the highest amount of bioaccumulation was found for the essential elements. For sevelar elements, significant differences were observed in various sampling sites. Based on the pollution load indexes (PLIs), two sites at Sharif university and Setad Bohran were more polluted than other areas. Exposed-to-control (EC) ratio values for Pb, Zn, Cr, Fe, Mn, Ni, Mg, and Co were also found in the range of 1.25-1.75. Based on the relative accumulation factor (RAF), the accumulation preference of elements by R. sinensis lichen was observed as Na > Cr > Cu > Fe > Mg > Ni > Zn > Mn > Co > Pb > Ca > K, respectively, which represents the significant ability of this species in the accumulation of elements such as Na, Cr, Cu and Fe. PCA and EF analysis indicated that trace elements adsorbed by lichen were mainly sourced from vehicle transportation.
Conclusion: This study demonstrates the application and importance of R. sinensis lichen in biomonitoring of air pollutants elements in urban areas. This approach can justify the suitability, accuracy and cost-effectiveness of lichen compared to other biomonitors for air pollutants and more importantly highlights its capability to the determination of wide levels of air pollution in large scales.
Azim Rabieimesbah, Soheil Sobhanardakani, Mehrdad Cheraghi, Bahareh Lorestani,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants produced by anthropogenic activities that contaminate all environmental matrices, including soils, and can enter the food chains. Therefore, this study was conducted for the analysis of PAHs compounds content in agricultural soils of Hamedan city, west of Iran, in 2021.
Materials and Methods: a total of 36 surface soil specimens were collected from 12 sampling sites in agricultural soils and after extraction of analytes based on the soxhlet method, the gas chromatography/mass spectrometry (GC–MS) method was used for the determination of PAHs compounds in the samples. Furthermore, soil samples were further analuzed for the amounts of pH, electrical conductivity (EC), and total organic carbon (TOC). Statistical analysis was performed using SPSS software.
Results: Results showed that 16 PAHs (∑16PAHs) total concentrations ranged from 435 to 3292 µg/kg with an average value of 1806 µg/kg. PAHs with higher molecular weight (≥ 4 rings) were dominant in PAHs profiles accounting for 78%. Based on the results, the mean concentrations of all 16 PAHs were lower than MPC established by MHWaS. Furthermore, the mean concentrations of Pyr, B(a)A, Chy, B(b)F, B(k)F, B(a)P, and B(ghi)P were higher than the MPC established by the Iranian Department of Environment.
Conclusion: Based on the results obtained, as the mean contents of some PAHs were higher than the MPC, therefore, periodic monitoring of soil contamination with PAHs is recommended for the environmental and human health aspects.