Risk Assessment of Trace Elements Toxicity Through Contaminated Edible Plants from Polluted Irrigation Canal at Giza Governorate, Egypt

To assess the leakage of sanitation service in urban areas on the contamination of water streams and soil besides, a risk assessment study was conducted through the intake of edible plants from polluted irrigated suburban area of El-Zomor area, Egypt. The results revealed that concentrations of trace elements were several folds higher in the studied site compared to the background level in the earth crust indicating that the soil of the studied area is contaminated with heavy metals. Therefore, contamination factor (CF) values of this area indicate that soils were considerably contaminated with Cd, moderately contaminated with Co, Cu, Pb and Mn, but showed signs of low contamination with other metals. Enrichment factor (EF) indicating that moderate enrichment of Cu and very significant enrichment for Cd were contributed to anthropogenic source. To assess the health risk, estimated exposure and risk index were calculated. For the non-carcinogenic risk, the studied elements were not found to cause any risks to the local population, since the hazard index (HI) for studied trace elements were lower than the safe level. The level of cancer risk associated with exposure to these elements falls within the range of safe limits (10-4–10-6) so we consider the risk is unacceptable.