Strontium is one of the rare heavy metals found in the sediments and water of the Nile River. By examining the metal concentration in 69 sampling points along the river between two Nile banks and the Middle, we could throw further light on its dispersion in the current study. High Sr concentrations were found in the eastern>western>middle regions with average concentrations of 344.3, 338.39, and 327.57ppm, respectively, due to the point sources such as industrial activities, sewage wastes, and agricultural discharge. High Sr concentrations were found in the West and East of Cairo (Samalut and Beni Suef) (395, 397, and 392 ppm). Various pollution indices, such as the Geo-accumulation index, Contamination factor, and Enrichment factor depiction, were used to determine the pollution level caused by this metal, ranging from low to moderate contamination. According to the extraction fractions, the occurrence nature of the element is as follows: Acid soluble > residual >Fe- Mn oxy-hydroxides (reducible)> organic (Oxidizable). The risk assessment code based on the Acid soluble fraction indicates moderate to high risk. Renal failure and baby bone growth problems are common in Egypt, impacting Sr concentration in sediments. The average Sr concentration in water is around (221.58µg/l), indicating that the water is perfectly safe to drink. The study's findings are useful in determining the extent of Sr metal pollution in the river. If not monitored, Sr concentration will be an issue in Egypt and Ethiopia following dam construction. After the dam is built, this study will serve as a baseline.

Heavy metals such as cadmium (Cd) pollute the environment. Heavy metal pollution endangers the Nile River since it serves as an irrigation and freshwater source for the cities and farms that line its banks. Water and sediment samples from the Nile River were tested for Cd content. In addition, a sequential experiment analytical method was performed to determine the metal’s relative mobility. According to the data, there is an average of 0.16 mg kg−1 of Cd in sediments. The BeniSuef water treatment plant and brick factory, the iron and steel factory of Helwan, the oil and detergent factory of Sohag, and the discharge of the cement factory in Samalut had the greatest concentration of Cd in their vicinity. According to the risk assessment code, there are four categories of Cd: residual (57.91%), acid-soluble (27.11%), reducible (11.84%), and oxidizable (3.14%). Bioavailable and mobile Cd levels in sediment and water were found in Beni Suef, Aswan; Helwan; Samalut; Sohag; and Helwan. Because the other metal is highly bioavailable, its concentration is not a risk factor at the Samalut station. Cd’s toxicity and bioaccumulation make it an extra hazard to aquatic animals and human life. There should be a deterministic approach to monitoring Cd near industrial sources.

Studying and understanding the complexity and interactions of different factors influencing stream sediment quality is necessary for the development of successful water quality management strategies. This study aims to evaluate the level of contamination by potentially toxic elements (PTEs) (As, Co, Cr, Cu, Mn, Ni, Pb, V, Zn) of the stream sediments of the Nile River. During the spring of 2019, river sediments were sampled at 23 sites along the Nile River. For each sample, one aliquot was digested in aqua regia and analyzed by ICP-MS for pseudo-total concentration, while for another aliquot, sequential extraction procedures were applied to determine chemical speciation. Compositional data analysis (CoDa) and k-means were applied to recognize the contribution of natural and anthropogenic sources, while pollution indices (EF, RAC) and sediment quality guidelines (SQGs) were applied to assess the ecological risk to biotic species. The results reveal that elements such as Cr, Mn, V and Fe, found in high concentrations in almost all samples (Cr up to 739 mg/kg, Mn up to 1942 mg/kg, V up to 507 mg/kg, Fe up to 98,519 mg/kg), have a natural origin, while the concentrations of Cu (up to 69 mg/kg), Ni (up to 88 mg/kg), Co (up to 42 mg/kg) and As (up to 9.8 mg/kg) are linked to both natural and anthropogenic processes. Sequential extraction shows that Mn, Co, Ni and, in some sites, Cu and Zn, are the most bioavailable elements. These elements present a high risk of toxicity, while the remaining elements imply a low-to-moderate risk.