Abstract

Access to safe drinking water is essential for public health. In Arua City, Northern Uganda, boreholes serve as a primary 
water source, but their safety may be compromised by radionuclide contamination. This study analyzed gamma-ray
emitting radionuclides (²²⁶Ra, ²³²Th, and ⁴⁰K) in borehole water samples from Ayivu East, Ayivu West, and Arua City 
Central using gamma spectrometry. Eighteen samples from 6 boreholes per division were assessed against UNSCEAR 
global averages. Results showed high variability in radionuclide concentrations. Several boreholes, particularly on Arua 
Hill’s slopes, had ²²⁶Ra levels exceeding the global average of 35 Bq/L, while ²³²Th remained below 30 Bq/L in all samples. 
⁴⁰K concentrations surpassed the global average of 400 Bq/L in all divisions. Absorbed dose rates in some boreholes 
exceeded 57 nGy/h, though annual effective doses remained below 0.41 mSv/y. Hazard indices in specific boreholes 
suggested health risks. The study recommends regular monitoring, geological assessments, safe drilling, public awareness, 
and water treatment to ensure water safety and protect public health.