Evaluation of Lead Concentrations in Soil and Seed of Wheat Farms and the Influence of Some Soil Characteristics on it (A Case Study: Khuzestan Province)

Environmental pollution caused by heavy metals such as lead is a serious and growing problem. Due to the importance of wheat in the human nutrition, this research was conducted to study concentration of lead in the soil and also seeds of wheat farms in Khuzestan Province. Therefore, in the agricultural year of 2007-2008, the soil and wheat seed samples were collected from 100 farms whose locations were specified using weighing sampling method. The lead concentrations in soil (total and available), and wheat seeds samples were measured. The result revealed that lead concentrations in soil and seeds in none of the studied regions exceeded the respective critical levels (50 and 30-300 mg/kg, respectively). Ezeh with an average of 0.01 µg/kg had the lowest amount of lead in the wheat seeds, while Bagh‌Malek with an average of 190 µg/kg had the highest amount. The mean concentration of available lead in the soils of study region was 0.6 mg/kg. The concentration of available lead had a negative and significant correlation (r=-0.2*) with the ECe. Also, lead concentration in wheat seeds had a positive and significant correlation (r=0.3**) with the amount of calcium carbonate equivalent. More lead concentration in seeds of bread wheat cultivars showed its higher potential for accumulation of lead than durum wheat.