Assessment of Tap Water Quality and Health Risks in Mymensingh City, Bangladesh

This study assesses the domestic water supply status, physicochemical quality, and associated health risks in a region reliant on groundwater-derived tap water. A cross-sectional survey revealed that 89% of households depend on tap water, yet 78% express significant concerns about its safety, prompting inconsistent treatment practices (45% treat water "seldom"). Physicochemical analysis of tap water samples identified critical contamination issues: 33.3% of samples exceeded Bangladesh (BD ECR 2023) iron (Fe) limits (0.3-2.05 mg/L), while 100% surpassed WHO guidelines (0.3 mg/L). Manganese (Mn) exceeded permissible levels (0.1 mg/L) in 33.3% of samples. Total coliform contamination (up to 12 CFU/100ml) was widespread, though fecal coliforms were absent. Principal Component Analysis (PCA) attributed 82.22% of water quality variance to dissolved solids (electrical conductivity, salinity) and metal contamination (Fe, Mn), linked to geogenic/anthropogenic sources. Health risk assessments revealed non-carcinogenic hazards, particularly for children, with Hazard Index (HI) values reaching 2.87-far exceeding the safety threshold (HI > 1). Iron posed the greatest risk (THQ up to 2.44 for children), underscoring vulnerabilities due to physiological sensitivity. Despite 67% of respondents reporting satisfaction with water quality, stark disparities exist between perception and analytical results, driven by aesthetic/metallic concerns. Urgent interventions are needed, including infrastructure upgrades to curb pipe corrosion, advanced metal removal filtration, and community water treatment education. Policymakers must prioritize stricter industrial regulations and routine monitoring. This study highlights the imperative to align public trust with scientific evidence to safeguard health in groundwater-dependent communities.