TITLE:
Index Based Water Quality Appraisal and Metal Driven Health Risk of Water Sources near Industrial Dumpsites in Makurdi, Nigeria
AUTHORS:
Barnabas Orngu Mnenga, Adams Udoji Itodo, Isaq Shaibu Eneji, Nguamo Surma, Mark Aondoakaa Tseen
KEYWORDS:
Water Quality Index, Toxic Metals, Industrial Dumpsites, Lead Exceedance, Hazard Index, Carcinogenic Risk, Makurdi, Nigeria
JOURNAL NAME:
Open Access Library Journal,
Vol.13 No.8,
August
13,
2026
ABSTRACT: Industrial dumpsites can impose complex pressure on nearby water sources through dissolved ions, oxygen demanding substances, microbial inputs and toxic metals. This study assessed the physicochemical quality, Water Quality Index, toxic metal burden and human health risk of water sources around fertilizer, dye, battery and paint dumpsite vicinities in Makurdi, Nigeria. Water categories comprised fertilizer dumpsite water sample (FDWS), dye dumpsite water sample (DDWS), battery dumpsite water sample (BDWS), paint dumpsite water sample (PDWS), and a comparison water sample (Comp) collected from a site removed from the industrial dumpsite vicinities, representing regional background conditions rather than an uncontaminated reference. Physicochemical variables, Fe, Pb, Cr, Cd, Zn, Mn and Cu concentrations, Water Quality Index values, chronic daily intake, hazard quotient, hazard index, carcinogenic risk and integrated site ranking were evaluated. The physicochemical profile showed strong site variation, with DDWS recording the highest electrical conductivity (1434 ± 1.21 µS/cm), total dissolved solids (758 ± 0.45 ppm), chloride (875 ± 5.67 mg/L) and chemical oxygen demand (176 ± 0.06 mg/L). Water Quality Index (WQI) values classified all water categories as excellent, ranging from 0.549 in FDWS to 1.230 in BDWS. This classification contrasted sharply with the toxic metal profile, where Pb exceeded the WHO guideline by factors of 825.0, 793.0, 888.0 and 718.0 in FDWS, DDWS, BDWS and PDWS, respectively. Cr and Cd also exceeded guideline values across the dumpsite water categories. Child ingestion hazard index (HI) values were consistently higher than adult values, and BDWS recorded the highest child ingestion carcinogenic risk (1.15214 × 10−5). The health risk assessment employed USEPA-derived exposure parameters for adult (BW: 70 kg, IR: 2.0 L/day) and child (BW: 15 kg, IR: 1.0 L/day) receptors. Each dumpsite category included both surface water (streams/rivers) and groundwater (wells) samples, pooled to reflect integrated water quality in each industrial vicinity. Integrated ranking placed BDWS first, followed by DDWS, PDWS and FDWS. The findings show that WQI alone is insufficient for classifying dumpsite adjacent water safety when metal exceedance and receptor specific health risk are present.