Assessment and comparison of heavy-metal concentrations in marine sediments in view of tourism activities in Hurghada area, northern Red Sea, Egypt

Abstract

The study discusses the geochemistry and texture of marine surface-sediments in selected areas along Hurghada area, in order to assess the possible influence of human activities on the composition of the sediments, to test for anomalous enrichments in heavy metals, and to evaluate and quantify metal release into the sea. The results have been compared with those of other studies conducted in Hurghada area, other areas of Red Sea and the world as well as existing guidelines of metals. The surface sediments are mostly fine sand, with increase in the coarse sand at the beach and close to high topographic areas of the bottom. The metals correlate directly with distance from the shoreline while correlate inversely with carbonates. This points to that the metal content of the investigated sediments is derived from the basement complex source materials and not from abundant elements in the marine carbonate sediments. Surface sediments reveal high total concentrations of Fe, Mn, Pb, and Zn at Desert Rose Resort transect (avg. 0.43%, 77.14, 5.00, and 19.70ppm respectively), Cd at El-Samaka Village transect and Abu-Shaar transect (avg. 0.15ppm), Cu at Tourist Harbour (avg. 8.80ppm), Ni at Abu-Shaar transect (avg. 20.80ppm), and Hg at El-Samaka Village transect (avg. 0.07ppm). In comparison, the metal levels obtained in the present study are in general lower and comparable in some cases to those found in Hurghada area and other areas along the Egyptian Red Sea coast during previously or post conducted studies. Comparing the current findings with other regional data and other areas in the world clarifies that the metal pollution in Hurghada area is still localized and low. A comparison of the gained data from this study with existing guidelines clearly indicates that nearly the metal concentrations were in the range of natural unpolluted sediments.