An Environmental Evaluation of Heavy Metals’ Soil Contamination of Shourab Region (South Kashmar – Khorasan Razavi)

The purpose of this research is to investigate the distribution of heavy metals and evaluating geo-accumulation and contamination factors on these elements in the stream sediments of Shourab Kashmar area. There are indications of some elements such as Mercury, Lead, Iron, and Copper that might be the cause for environmental pollution in this area.

After processing of satellite images and performing geological studies, 21 samples of stream sediments were gathered. By determining the salinity, pH, and EC parameters as well as the soil texture of samples, 14 samples were tested in order to study the concentration of heavy metals with the ICP-OS systems in the ZarAzma Laboratory. The collected results were processed and studied using GIS, SPSS, and Excel software.

With the exception of the Silver, Copper, Cadmium, Cobalt, Chromium, and Nickel elements which show some level of contamination, there is no evidence of environmental pollution, in the stream sediments in this area. The amount of pH from 7.5 to 8.2 and EC from 0.3 µs/cm to 5 µs/cm and salinity from 150 to 2500 are varying.

There is a similarity between the distribution of the Nickel, Cobalt, and to some degrees, Chromium in the stream sediments of the study area. This can be related to the volcanic rocks which are mainly intermediate in composition. The Lead and Zinc are mainly concentrated on the north and some towards east of the area, and the Arsenic and Antimony elements in the north and north-west of the study area. The origin of these elements could be connected to mineralization in this area, which has not been focused on so far.