TITLE:
Integrated Assessment of Physicochemical Characteristics and Health Risks of Groundwater from Wells in the Continental Terminal Aquifer of Bonoua (Southeastern Côte d’Ivoire) Using WQI, HI, and PCA during the Rainy Season
AUTHORS:
Tohouri Privat, Anongba Braphond Rodrigue Vincent Binjamin, Orou Kotchi Rodrigue, Adja Miessan Germain
KEYWORDS:
Groundwater, Heavy Metals, Water Quality Index, Health Risk Assessment, Principal Component Analysis, Côte d’Ivoire
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.13 No.12,
December
9,
2025
ABSTRACT: Groundwater in Côte d’Ivoire is increasingly exposed to contamination from both natural and anthropogenic sources. This study evaluates the physicochemical characteristics and potential health risks of well water from the Continental Terminal aquifer in Bonoua, southeastern Côte d’Ivoire, during the rainy season. Thirty groundwater samples were collected and analyzed for 28 parameters, including major ions and heavy metals. Results revealed low mineralization (mean electrical conductivity: 161.85 µS/cm) and acidic conditions (mean pH: 5.16). Concentrations of aluminium (504 µg/L), manganese (998 µg/L), iron (1023 µg/L), and cadmium (78 µg/L) exceeded the World Health Organization drinking-water guidelines. The Water Quality Index (WQI) ranged from 7.08 to 758.40 (mean: 136.55), indicating that most wells (77%) were unsuitable for direct consumption. Non-carcinogenic health risk assessment revealed higher vulnerability among children (mean Hazard Index, HI: 19.50) compared with adults (mean HI: 8.49), with most wells exceeding the safety threshold (HI > 1). Principal Component Analysis (PCA), explaining 79.29% of the total variance, identified three main pollution sources: natural mineralization, acid-driven metal mobilization, and anthropogenic contamination. These findings highlight the urgent need for strengthened groundwater monitoring and sustainable management strategies in the Bonoua region.