Iranian Journal of

Background and Objectives: Arsenic contamination is of great environmental concern due to its toxic effects as a carcinogen. In order to assess soil arsenic contamination and its distribution patterns, surface soil samples collected from the urban areas of Arak were analyzed. Materials and Methods: Totally, 62 surface soil samples were collected from depth of 0–20 cm of different locations including parks, green spaces, agricultural, roadsides, and squares of Arak City. The spatial distribution of arsenic in soil was mapped using GIS and kriging method. Results: The concentration of arsenic in the surface soil of Arak City was between 2.2- 10.8 mg/kg (average: 5.78 mg/kg). Spatial analysis showed that arsenic contamination enhances in the city center and there was an increasing trend from south to north. In addition, the mean arsenic concentration in the urban topsoil samples from Arak was lower compared with mean concentration for other cities around the world. Conclusion: It seems that arsenic in soil is controlled by natural and anthropogenic factors. The highest concentrations of arsenic in center and the north areas reflected arsenic loading is originated from anthropogenic sources such as vehicles and industrial processes.

Background and Objectives: Perchlorate, as an emerging contaminant, has attracted notice of the most individuals and organizations. Presence of perchlorate in the human body can lead to inappropriate regulation of metabolism in adults. Moreover, due to inhibition of iodide uptake in the thyroid gland, it causes neurological and behavioral problems in infants and children. United States Environmental Protection Agency (EPA) has enacted 15 µg/L perchlorate in drinking water as a guideline value. Regarding the possible sources and potential presence of perchlorate in the environment of the study area, and the unique characteristics of this pollutant, such as extreme water solubility, high mobility in soils and stability in the environment, the status of its contamination was assessed in soil, surface water and drinking water in the study area (Khorramshahr County).

Materials and Methods:  Soil and water samples were taken during February to April, 2013. Combined sampling was used for soil sample collection and the random sampling was used for water (surface and drinking water) samples. Each sample was analyzed using ion chromatography. In this study, 15 samples of surface soil and 22 samples of surface and drink water were tested for perchlorate analysis.

Results: It was found that all surface soil and water samples collected from the study area were contaminated with perchlorate and exceed the standard level. Concentration of perchlorate in surface water and drinking water was 1400-5800 and 700-5900 µg/L respectively and in surface soils was 3.3-107.9 mg/kg.

Conclusion: The assessment of perchlorate in soil, surface water, and drinking water in the study area is extremely higher than recommended standards and therefore is a threat to the health of consumers.