Analysis of Heavy Metal Contamination in Drinking Water Sources in Kano Metropolis, North West Nigeria

Access to safe drinking water remains a critical public health challenge in rapidly urbanising cities across Nigeria. This study investigates the concentrations of selected heavy metals, including lead, cadmium, chromium, and arsenic, in drinking water sources across Kano Metropolis, North West Nigeria. Water samples were collected from boreholes, hand-dug wells, and pipe-borne water distribution points in five local government areas over a three-month period. Samples were analysed using atomic absorption spectrophotometry following standard digestion protocols recommended by the World Health Organization. Results were compared against Nigerian Standard for Drinking Water Quality (NIS 554:2015) and WHO guidelines. Preliminary findings suggest that lead and cadmium concentrations in open wells exceeded permissible limits in three of the five sampled areas, potentially linked to artisanal activities and indiscriminate waste disposal near water bodies. Physico-chemical parameters including pH, turbidity, total dissolved solids, and electrical conductivity were also assessed. Statistical analysis using one-way ANOVA revealed significant spatial variation in metal concentrations across sampling zones. This study contributes local data to existing literature on water quality in densely populated Nigerian cities and recommends regular monitoring, improved waste management practices, and public awareness campaigns to safeguard community health. Keywords: heavy metals, drinking water, Kano, atomic absorption spectrophotometry, water quality