Trace elements speciation and sources characterization in the main watercourses, middle-upper Egypt

Abstract

Water contamination by mutagenic microchemicals is a worldwide problem. To evaluate the overall water quality and identify the source(s) of pollutants (B, Fe, Cu, Mn, Ni, Pb, Cd, and Cr) in different watercourses in middle-upper Egypt, we analyzed 66 surface water samples collected from the significant waterways. In addition to trace pollutants, 15 physicochemical parameters (pH, Temperature, EC, alkalinity, DO, BOD, COD, Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃^-, SO₄^2-, Cl^-, and NO₃^-) were measured. Multivariate statistical approaches such as exploratory principal component analysis, hierarchical cluster analysis, and correlation matrix analysis were applied to explore the sources of the contaminants. Data reveal that surface water quality in the investigated area is threatened by high concentrations of trace elements, which are higher than the permissible limits recommended by WHO guidelines and Egyptian standards for drinking water and irrigation purposes. Statistical analyses suggest that surface water contamination is the result of interference of natural (geogenic related to rock–water interaction) and human (interrelated to agrogenic and domestic sewage) inputs. The study will help decision-makers to take appropriate actions for freshwater sustainable management and protection. Moreover, surface water should be treated before use for drinking purposes.

Keywords:

• risk assessment
• natural factors
• anthropogenic activities
• metal pollutants
• hydrochemistry
• redox conditions

Acknowledgments

Moustafa Gamal Snousy would like to express his deep gratitude to Mr. Mohammed Abd-Almageed Hasan, a senior English teacher at the Egyptian Ministry of Education for his patient guidance, enthusiastic encouragement, and useful efforts in editing this research paper. The authors are grateful for the constructive comments of reviewers and editors.

Conflict of interests

The authors declare that they have no conflict of interest.

Additional information

Funding

Prof. Peiyue Li is grateful for the financial support received from the National Natural Science Foundation of China (42072286 and 41761144059), the Fundamental Research Funds for the Central Universities of CHD (300102299301), the Fok Ying Tong Education Foundation (161098), and the Ten Thousand Talents Program (W03070125).