Assessing Health Risk Mitigation Efficiency of the Halabja Water Treatment Plant in Drinking Water Purification

Water quality management represents a paramount public health issue, especially within areas where surface water resources are particularly susceptible to contamination. This investigation evaluates the efficacy of health risk mitigation provided by the Halabja Water Treatment Plant (HWTP) . The facility processes water sourced from Sirwan Lake, employing methodologies such as sedimentation, filtration, and disinfection. The primary aim was to ascertain the removal efficiency of trace elements (e.g., As, Pb, Cd, and Cr) throughout various treatment phases, while also examining the potential health hazards linked to the consumption of tap water.
Water samples were systematically collected on a monthly basis over a two-year period (2022–2023) at three distinct phases: raw water, treated water, and tap water. Analytical techniques encompassed trace element quantification alongside health risk evaluation utilizing hazard quotient indices (HQ). The results indicated a significant reduction in turbidity (from 59 NTU in raw water to between 0.1 and 5 NTU in treated water) as well as in heavy metal concentrations. For instance, cadmium levels diminished from 0.48 µg/L in raw water to 0.018 µg/L in treated water, while arsenic concentrations were reduced from 2.951 µg/L to 2.503 µg/L. Nonetheless, occasional exceedances of WHO standards were detected in tap water, with lead concentrations peaking at 9.4 µg/L in November, suggesting potential recontamination during the distribution process.
Hazard indices remained below the critical threshold of 1 for the majority of metals, signifying manageable health risks. The highest hazard index for pre-treated water was recorded at 0.61 (in September), which subsequently declined to 0.15 following treatment. These findings underscore the success of HWTP in diminishing contaminants. This study contributes to the optimization of water treatment methodologies and emphasizes the critical importance of ongoing monitoring to ensure the provision of safe drinking water.