Determination of cobalt concentration using nonlinear regression and Monte Carlo simulation in Zafarghand Region, Isfahan

Contamination of heavy metals can change the properties of the soil, biological reduction activity of soilnutrients, also, by entering the food chain, it is considered dangerous for humans. Considering the importanceof pollution in the environment, in this research, it has been tried to introduce an estimator to determine theconcentration of Co element. In this research, Zafarghand exploration area is considered as a case study(Central Iran, Northeast of Isfahan). There were lithogeochemical data of 184 samples collected and analyzedfor major and trace element concentration by ICP-MS. In the first step, nonlinear regression was used tocreate a model and estimate the concentration of Co element. In the next step, Co concentration value wassimulated with the help of the created model and the Monte Carlo simulation method. The results obtainedfrom the combination of nonlinear regression and Monte Carlo simulation show the accuracy and acceptableefficiency of this simulation, so that the mean value of Co concentration was close in the modeling to thevalues measured in the laboratory. According to the obtained result, the level of Co element in the studiedarea was in the range of (0.45-0.75) (mg/kg) with a confidence level of 90 percent. This value is below thebackground limit (less than 1.3010). In addition, in this research, sensitivity analysis was used to determinethe most effective input parameter in determining the concentration of Co. Based on the obtained results,the most influential variable in this estimate is the amount of iron It should be noted that the use of thismethodology is recommended for determining other heavy metal concentrations in different study areas.