Spatiotemporal Assessment of Heavy Metal Pollution in the Tigris River

The emphasis of the world on sustainable water quality and frequent monitoring of pollutants has grown greater to protect public health and biodiversity, aimed at limiting human activities that lead to water pollution and conserving water resources. The objective of this study was to evaluate the levels of pollution and concentrations of different heavy metals in sediment and water samples taken from four locations along the Tigris River at Baghdad City, Iraq, during 2024. In order to investigate the variations in conditions between the wet and dry seasons, samples were collected during each. Among the elements under analysis were lead, nickel, chromium, zinc, and iron. The samples were analyzed for heavy metals using Atomic Absorption Spectrophotometry (AAS) following standardized procedures (APHA). Data on the pollution index (PI) showed that the effect on water quality ranged from very little to modest. Reading on the Metal Index (MI) ranged from 1.87 to 3.66. River sediments were evaluated using geochemical markers, including the geoaccumulation factor and contamination factor. For nickel, zinc, lead, and chromium, the geoaccumulation index values showed no pollution. Iron tests turned up moderate to significant contamination at several sites. Except for iron, which showed notable contamination, the index values for contamination variables were essentially within the low contamination range. The Sediment Quality Guidelines (QSm) ranged in value from 3.752 to 8.44. Since QSm exceeded 0.5, all sites fell into the third category of potential danger for aquatic life (possible hazard for aquatic life), implying that negative effects on aquatic life could not be excluded. The Tigris River is not heavily polluted; it has moderate contamination.