Spatial Distribution of Heavy Metal Contamination and Ecological Risk Assessment in Water from the Danube River

Abstract: Heavy metals are considered dangerous contaminants due to the possibility of bioaccumulation and toxic effects on environment and human health. Six metals exhibiting a greater relevance to the aquatic ecosystem in terms of toxic effects (Cd, Cr, Cu, Zn, Ni and Pb) were analyzed from water samples collected monthly from ten sites, during May 2012 - April 2015. The levels of heavy metals in water samples were measured using atomic absorption spectrophotometry (AAS). Results obtained emphasized that the average concentrations of the studied metals from water have decreased as follows: Zn>Cu>Ni>Cr>Pb>Cd. Spatial distribution maps of studied heavy metals were performed using ArcView 9.3 software. Quantifying the risk of aquatic ecosystem exposure to heavy metal pollution was carried out based on ecological hazard quotient (HQ). Exposure to heavy metals in water pose no risk factor.