Metal Pollution, Environmental Assessment and Suggested Solutions in the Recent Bottom Sediments of Qaroun Lake, Fayoum, Egypt

Abstract

Qaroun Lake is located in the deepest area of the Fayoum depression, within the western desert and about 83 kilometres south of Cairo. The current study aimed to determine the distribution of polluting elements resulting from the wastewater discharge of these drains as a significant source of pollution. Sediment in Qaroun Lake was sandy silt in the east zone, while the middle and west were silty sand and sandy silt. The heavy metals mentioned were found in higher amounts in the eastern and middle parts of the lake's recent bottom sediments, in contrast to the western area, where their concentration was lower. The metal pollution in the lake was measured by using single indices like contamination factor, enrichment factor, ecological risk factor, and index of I geo accumulation, combining indices like the degree of contamination, ecological risk factor, and potential ecological risk index. The results revealed that the distribution of the measured heavy elements over the lake was found in the range of (0.55–7.72%), (227–1840 ppm), (43–174 ppm), (24–76 ppm), (18–42 ppm), (48–114 ppm), (31–94 ppm), (21–49 ppm), and (583–4944 ppm) for Iron, Manganese, Zinc, Copper, Lead, Cobalt, Nickel, Rubidium, and Strontium; respectively which means all parts of Qaroun Lake show high contamination levels (Cd). The ecological risk factor (PLI) indicates no contamination in most stations, except for one close to the polluted El-Wadi drain. The potential ecological risk index (RI) is low in all stations around Qaroun Lake.