Ecological Risk Assessment of Heavy Metals in the Atmospheric Dry Deposition in Hamedan City

Abstract

Background: Dust pollution can cause serious ecological problems. Therefore, the current study aimed to carry out the ecological risk assessment of heavy metals (Co, Cr, and Mn) in the atmospheric dry deposition in Hamedan city, Iran. Methods: In the current study, 36 samples of atmospheric dry deposition were collected from three regions of Hamedan city from September to October 2014. After sample digestion in the laboratory, the content of the metals was determined using inductively coupled plasma-optical emission spectrometer (ICP-OES). All statistical analyses were performed using the SPSS statistical package. Results: The results showed that the average contents (mg kg-1) of Co, Cr, and Mn in the studied samples were 0.23 ± 0.06, 0.89 ± 0.20, and 8.10 ± 0.70, respectively. The results of the potential ecological risk analysis of heavy metal pollution in the atmospheric dry deposition in Hamedan city demonstrated that the risk index (RI) of stations A, B, and C with an average of 0.13 is at low ecological risk levels. Conclusions: In present study the potential ecological risk of Co, Cr, and Mn was at low levels. Also, the results showed that the Co and Mn contents in the atmospheric dry deposition collected from the stations with heavy traffic intensity were significantly higher than that in the other stations. Therefore, control of the anthropogenic sources that cause discharge of hazardous compounds, particularly toxic heavy metals, into the atmosphere is recommended.