Spatial and Temporal Variability of Some of Heavy Metals in Aerosols of Lenjanat Region, Esfahan

Document Type : Research Article

Authors

1 Shahrekord University

2 isfahan university

Abstract

Introduction: Heavy metals released from stationaryand mobile origins can be transported in water, air and soil and can be even absorbed by plants, animals and human bodies. Trace elements are currently of great environmental concern. Nowadays, one of the most important environmental problems is pollution of agricultural soils occurs by heavy metals due to human activities. Atmospheric subsidence is one of the main sources of these elements which can result from industrial activities, fertilizers, sewage sludge, compost and pesticides. Heavy metals mapping of the atmosphere dusts indicates the status of pollution and its intensity in industrial regions. This information can also be used as a guideline for better management and pollution control. This study was performed to investigate the spatial and temporal availability of heavy metals in atmospheric dusts of Lenjanat region, Isfahan where agricultural land is extensively surrounded by industrial activities like steel making factory (Esfahan), cement making factory (Sepahan and Esfahan) and Bamalead mine.
Materials and Methods: Sampling was done from 60 points with the same altitude(three to six meters from the ground)and their location was recorded by GPS. Glass traps (1×1 m2) covered by plastic mesh (2 × 2 cmvents) were used to trap the dusts for four seasons of the year. Collected dust samples were passed through a 200 mm mesh screen size and the total weight of the dusts and the heavy metals content of Cd, Zn, Cu, Ni and Pbwere determined(with HNO3 60%). Data analysis was performed using Statistical 6.0 software. Analysis of spatial data via variogram was calculated and performed using Variowin, 2.2 software packages. After determination of the best fitting model, kriged maps of the total concentration of heavy metals were prepared by Surfer 8 software.
Results and Discussion: The average concentrations of Zn, Pb and Cd in dust in most parts of the study area were much higher than the soil standard values and the maximum value was around the Zn and Pb mines. However, the concentrations of Cu and Ni were higher than the standard values only in some parts of the area. Comparison of the averages for different seasons showed that in most cases there were significant differences between the concentrations of the various elements. A significant correlation was observed among Pb, Zn and Cd concentrations in all seasons indicating similar origin of these elements. The average dust deposition rate in the summer was more than the other seasons. Moreover, in all seasons except the spring and fall, there was a significant difference between the average dust deposition rates. Kriged maps of Zn, Cd, and Pb showed that the maximum concentrations of these elements occurred near the Pb and Zn Bama mine and the concentrations of these elements decreased with increasingthe distance from the mine. The contamination was lower in the spring and higher in the summer. Based on the kriged maps, samplingfrom one seasononly can be used to assess the trend of element contamination but if the objective focuses on absolute heavy metals values, season strongly influences the results and interpretation from one season can be misleading. The determination of the amounts of dust and their heavy metal contents in different wind directions is recommended to identify the source of dusts and heavy metals.
Conclusion: Results showed a significant difference among the mean values of dusts for the different seasons except for the spring and fall. The mean values of Pb and Cd in all seasons and Zn except for the spring were higher than the threshold values reported for the soils. A significant correlation was observed among the concentrations of some elements which may suggest their same origin. Interpretation of kriged maps showed that zinc and lead Bamamine in the region could be the main source of the contamination of Zn, Pb and Cd. According to quantitative calculations, a low accordance was observed for the pattern and the values of each element in different seasons. This can be related to the wind velocity and its direction, intensity of industrial and mining activities and also the amount of humidity of soil and air during the year. Interpretation of atmospheric data based on one season may be considerably misleading.

Keywords: Atmosphericdusts, Heavy metals, Season

Keywords


1- Amini M. 2004. Modeling the accumulation of heavy metals in agricultural ecosystems and evaluation of uncertainty in the region.Soil Science PHD thesis. Faculty of Agriculture, Isfahan University of Technology.(in Persian)
2- Baghayi A.H., Khademi H.V., and Mohammadi C. 2007. Spatial analysis of lead and nickel absorbent Geostatistics around two poles of Isfahan Technology. Journal of Agricultural Sciences and Natural Resources, 4: 20-11. (in Persian)
3- Boruvka L., Vacak O., and Jeilicka J. 2005. Principle Component Analysis as a tool to indicate the origin of potentially toxic elements in soil. Geoderma, 28: 289-300.
4- Dankoub Z. 2010. Magnetic susceptibility spatial correlation with the concentrations of some heavy metals in surface soils of the Isfahan. Soil Science MA thesis. Faculty of Agriculture, Isfahan University of Technology.(in Persian)
5- Deboudt K., Flament P., and Bertho B. 2004. Cd, Cu, Pb and Zn Concentrations in Atmospheric Wet Deposition at a Coastal Station in Western Europe.Water Air and Soil Pollution, 151:335-359.
6- Dvonch J.T., Morishita M., Hall N.L., Barres J.A., and Keeler G.J. 2012. Assessing the Sources of Atmospheric Mercury Wet Deposited in Florida, USA. 16th International Conference on Heavy Metals in the Environment, 23-27Sep. 2012. ICHMET, Rome, Italy.
7- FOEFL (Swiss Federal Office of Environment, Forest and Landscape). 1998. Commentary on the ordinance relating to pollutants in soils (VBBo of July 1, 1998).
8- Gallavardin S., Lohmann U., and Cziczo. D. 2008. Analysis and differentiation of mineral dust by single particle laser mass spectrometry. International Journal of Mass Spectrometry, 274: 56-63.
9- Ghazaban. F. 2002. Environmental Geology, Tehran University Press. Tehran. (in Persian)
10- Gupta U.C., and Gupta S.C. 1998. Trace element toxicity relationships to crop production and livestock and human health: implications for management. Communications in Soil Science and Plant Analysis, 29: 1491-1522.
11- Hojati S., Khademi H., Cano A.F., and Landi A. 2012. Characteristics of dust deposited along a transect between Central Iran and the Zagros Mountains. Catena, 88:27-36.
12- Jarup L. 2003. Hazards of heavy metal contamination. British Medical Bulletin68: 167-182.
13- Jorkesh Sh. 2012. The relationship between magnetic susceptibility and the concentration of heavy metals in contaminated soils and dust atmosphere Lenjanat, Isfahan. Soil Science MA thesis. Faculty of Agriculture, shahrecourd University.(in Persian).
14- Leung Anna O.W., Duzgoren-Aydin Nurdan S., Cheung K.C., and Wong Ming H. 2009. Heavy Metals Concentrations of Surface Dust from e-Waste Recycling and Its Human Health Implications in Southeast China, Environmental science technology, 42:2674- 2680.
15- Mahmoudi Z. 2011. Geochemical and mineralogical characterization of atmospheric dust.Soil Science MA thesis, Faculty of Agriculture, Isfahan University of Technology.(in Persian)
16- Meza-Figueroa D., De la O-Villanueva M., and De la Parra M.L. 2007. Heavy metal distribution in dust from elementary schools in Hermosillo, Sonora, Mexico. Atmospheric Environment, 41: 276–288.
17- Mohajer R. 2013. The spatial distribution of heavy metals in the soil map units and their relation to accumulate in the tissues of plants, animals and the prevalence of gastrointestinal cancer in Lenjanat, Isfahan (medical dirt). Soil Science PhD thesis. Faculty of Agriculture, shahrecourd University.(in Persian)
18- Mohammadi J. 2006. Pedometer (Spatial Statistics). Volume II. Pelk Publishing.(in Persian)
19- Movahedi Rad Z. 2007. Spatial analysis of zinc, lead, nickel and cadmium in soils of Qom province. Soil Science MA thesis. Faculty of Agriculture, Isfahan University of Technology.(in Persian)
20- Rossiter D.G. 2000. Methodology for Soil Resource Inventories, 2nd. Revised Version, Soil Science Division, International institute for Aerospace Survey and Earth Science (ITC), 132 pp.
21- Salehi M.H., Mohajer R., and Mohammadi J. 2012. Accumulation of Cadmium and Lead in Soils and Vegetables of Lenjanat Region in Isfahan Province, Iran, 16th international conference on heavy metals in the environment (ICHMET). E3S Web of Conferences, 23-27 Sept. 2012. Rome, Italy.
22- Schmeling M. 2003. Seasonal variations in diurnal concentrations of trace elements in atmospheric aerosols in Chicago. Analytica Chimica Acta, 496: 315–323.
23- Sahebghadam Lotfi A. 1988. Lead poisoning due to its metabolism, Tarbiat Modarres University Press. Tehran.(in Persian)
24- Shi G., Chen Z., Xu S., Zhang J., Wang L., Bi C., and Teng J. 2008. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China. Environmental Pollution, 156: 251-260.
25- Ta W., Xiao H., Cou J., Xiao Z., Yang G., Wang T., and Zhang X. 2004. Measurment of dust deposition in Gausu Province China 1986-2000. Geomerplology, 57: 41-51.
26- Taghipur A.D., Khademi H., and Ayoubi Sh.A. 2010. The spatial concentration of lead and zinc in surface soil and its relationship with the parent material and the use of part of Hamedan province.Journal of Soil and Water (Agricultural Science and Technology), 1(24): 144- 132.(in Persian)
27- Trang T., Duong T., and Lee B.K. 2011. Determining contamination level of heavy metals in road dust from busy traffic areas with different characteristics. Journal of Environmental Management, 92: 554- 562.
28- Zimdahi R.L., and Skogerboo R.K. 1997. Behavior of lead in soil. Environment of Science Technology 11: 1202-1207.
29- Zorasvand A.R., Rastmanesh F., Pourkaseb H., and Azarmi Z. 2012. The effect of dust on the phenomenon of heavy metals in selected species of plants and soil in Ahwaz. Journal of Modern Applied Geology, 2(1): 101-112.(in Persian)
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