V2I8P44

Assessment of Fluoride and Arsenic Levels in Rural Drinking Water: A Geochemical and Health Risk Perspective. A Case Study of Uromi, Edo state, Nigeria

Ugah Chukwuemeka S^1*, Nwite Eammanuel C², Anyira-Fasanmi Mary  Ifeoma¹

Abstract

Access to safe and clean drinking water is a fundamental human right and a critical determinant of public health, particularly in rural communities of developing nations. This study assessed the levels of fluoride and arsenic in groundwater sources used for drinking in Uromi, a rapidly expanding rural-urban town in Edo State, Nigeria. Ten sampling locations were selected based on spatial distribution and population dependence on borehole and hand-dug well water. Water samples were collected during the dry season and analyzed using standard geochemical methods, including ion-selective electrode and atomic absorption spectrophotometry (AAS) techniques. The results revealed that fluoride concentrations ranged from 0.76 to 2.15 mg/L, with the highest recorded at Eguare and the lowest at Efandion. Arsenic levels varied from 0.002 to 0.018 mg/L, with elevated values observed in samples from Market Square and Idumoza. Notably, 30% of the water samples exceeded the WHO permissible limit of 1.5 mg/L for fluoride, while 40% exceeded the WHO guideline value of 0.01 mg/L for arsenic, indicating significant potential for chronic exposure risks. The spatial variability of fluoride and arsenic concentrations suggests a combination of natural geochemical processes (e.g., leaching from fluoride-bearing minerals and arsenopyrite) and possible anthropogenic influences from waste disposal and agrochemical runoff. The estimated daily intake (EDI) and hazard quotient (HQ) for children and adults show a higher risk for children, particularly in areas with elevated contaminant levels. This study highlights the urgent need for continuous monitoring of groundwater quality in Uromi and similar rural regions, coupled with public health interventions such as water treatment, community education, and policy enforcement. The findings provide critical data for local authorities and environmental health planners to develop sustainable strategies for mitigating the health risks associated with fluoride and arsenic in drinking water.

Keywords:

Fluoride, Arsenic, Groundwater contamination, Drinking water quality, Health risk assessment, Geochemical analysis, Rural water supply, Uromi, Nigeria, WHO standards