التوزيع الجغرافي لملوثات المعادن الثقيلة في مياه نهر دجلة واثارها البيئية في محافظة بغداد

Abstract

The Tigris River is the main water source in Baghdad, serving domestic, agricultural, and industrial needs. However, increasing human activities, particularly industrial discharges, have led to elevated levels of heavy metal pollution in its waters. This study aimed to evaluate the spatial distribution of selected heavy metals, including lead (Pb), iron (Fe), nickel (Ni), and chromium (Cr), in different sites of the river within Baghdad, using the Pollution Index (PI) and Metal Index (MI) during the dry and wet seasons. Results revealed that some metal concentrations exceeded both Iraqi and international permissible limits, with lead (Pb) being the most critical pollutant, consistently surpassing standard values. Furthermore, PI and MI values were higher in the dry season compared to the wet season, mainly due to increased evaporation and reduced water discharge. These findings highlight a significant environmental and public health risk resulting from heavy metal accumulation in the river system, emphasizing the urgent need for stricter environmental policies and effective monitoring of industrial wastewater discharges to protect water quality in Baghdad.