The Sediments of the Tigris as an Indicator of Environmental Pollution: The Relationship between the Nature of the Sediments, the Accumulation of Pollutants and their Effects on Health

Ameerah Khattab Madhi; Raad Mahmoud Nasif Al-Khafaji; Jinan S.  Al-Hassany

doi:10.30526/39.3.4291

Authors

Ameerah Khattab Madhi Department of Biology, Collage of Education Pure Science Ibn Al-Haitham, University of Baghdad, Iraq. https://orcid.org/0009-0009-7639-3203
Raad Mahmoud Nasif Al-Khafaji Department of Biology, Collage of Education Pure Science Ibn Al-Haitham, University of Baghdad, Iraq. https://orcid.org/0009-0000-7764-3715
Jinan S. Al-Hassany Department of Biology, College of Science for Women, University of Baghdad, Iraq https://orcid.org/0000-0002-7360-8434

DOI:

https://doi.org/10.30526/39.3.4291

Keywords:

Tigris River, heavy metal pollution, total coliforms, physical and chemical properties, risks to human health, environmental pollution

Abstract

The Tigris, a vital source of fresh water in Iraq, is a major source of pollution. Its sediments act as sinks and carriers of pollutants and pose a burden on the environment and a health risk to the population. A study analyzed the chemical and biological pollution of sediments from five areas affected by domestic wastewater discharges in the winter of 2025. The study examined the physico-chemical properties of the sediments, including particle size distribution, organic matter content, pH, electrical conductivity, and total dissolved solids, as well as their relationship to pollutants such as heavy metals and total coliform bacteria. The results showed a significant increase in cadmium and nickel concentrations, especially in areas with high organic content. In contrast, iron remained within the globally permitted limits, while concentrations of chromium and lead were relatively low. Grain size analysis revealed that all sediments were of the sandy silt type, which is associated with the stabilization of heavy elements within the sediments, especially in a slightly alkaline environment with normal EC values. High levels of total coliform bacteria were detected at all sites, indicating widespread microbial contamination directly related to wastewater discharge. The non-cancer health risk (HQ, HI) and cancer risk (CR) coefficients were then calculated to assess potential human health impacts of heavy metals on human health. Some sites had levels that exceeded the permitted limits, indicating potential health risks that require attention and monitoring. These results underline the need to improve wastewater management and strengthen river pollution monitoring programs to reduce potential environmental and health risks.

Author Biographies

Ameerah Khattab Madhi, Department of Biology, Collage of Education Pure Science Ibn Al-Haitham, University of Baghdad, Iraq.

Department of Biology, College of Education Pure Science Ibn Al-Haitham, University of Baghdad, Iraq.
Raad Mahmoud Nasif Al-Khafaji, Department of Biology, Collage of Education Pure Science Ibn Al-Haitham, University of Baghdad, Iraq.

Department of Biology, College of Education Pure Science Ibn Al-Haitham, University of Baghdad, Iraq.
Jinan S. Al-Hassany, Department of Biology, College of Science for Women, University of Baghdad, Iraq

Department of Biology, College of Science for Women, University of Baghdad, Iraq

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