Assessment of Heavy Metal Contamination in Groundwater Sources Within Selected Local Government Areas of Ilorin, Kwara State, Nigeria

Abstract

This study investigated the levels of heavy metal contamination — specifically lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) — in groundwater sources across three local government areas of Ilorin, Kwara State, Nigeria. Water samples were collected from 45 boreholes and hand-dug wells between January and March 2024 and analysed using Atomic Absorption Spectrophotometry (AAS). Results indicated that 62% of sampled sources exceeded WHO permissible limits for lead, with the highest concentration recorded in Ilorin South LGA (0.089 mg/L). Cadmium levels were within acceptable limits in all but three locations. The study recommends urgent remediation measures and public health interventions, including regular monitoring of groundwater quality and enforcement of industrial waste disposal regulations in the affected areas