Mobility and potential ecological risk assessment of copper and zinc in alluvial and marine soils in the North Nile Delta, Egypt.

Copper (Cu) and zinc (Zn) are micronutrients needed for organisms, however, they are heavy metals and may become toxic to the organisms when exceeding the allowable limit in the environment. Two soil types of marine and alluvial were sampled in the North Delta, Egypt. Copper (Cu) and zinc (Zn) were analyzed to investigate the availability and to evaluate ecological risk assessment and identify pollution sources. Cu and Zn were extracted from sol samples by DTPA-TEA. The higher content of Cu was recorded in alluvial soil, especially in the surface, while Zn concentrations in both soils didn’t differ with depth. Six indices were used in this study to evaluate the potential ecological risk of Cu and Zn in the examined soils. The results of these indices revealed that affecting Cu and Zn anthropogenically in some profiles of the studied soils. As well, the results of principal component analysis (PCA) showed that Cu and Zn in marine soils mainly originated from anthropogenic source, while this is true in alluvial soil in Zn only. Human and agricultural activities may be the main source of Cu and Zn especially fertilizers and pesticides, which indicates that there may be environmental threating by those metals in the study area in the future.