APPLICATION OF ICRP 116 AGE-SPECIFIC DOSE COEFFICIENTS FOR STRATIFIED ASSESSMENT OF ANNUAL EFFECTIVE GAMMA RADIATION DOSE IN DUTSIN-MA, NIGERIA

Conventional environmental radiation assessments commonly rely on adult-averaged dose conversion coefficients, potentially underestimating age-dependent exposure and health risks. This study applies age-specific dose coefficients from ICRP Publication 116 to evaluate stratified annual effective gamma radiation doses and associated cancer risks in Dutsin-Ma, North-Western Nigeria. Previously measured activity concentrations of ⁴⁰K, ²²⁶Ra, and ²³²Th in twenty bedrock samples were used to recalculate absorbed dose rates using the UNSCEAR model and subsequently converted to age-dependent annual effective doses for infants, children, adolescents, and adults. The mean absorbed dose rate was 47.32 ± 9.86 nGy h⁻¹, approximately 20% below the global average, with all conventional radiological hazard indices remaining within recommended safety limits. However, age-stratified analysis revealed a marked increase in effective dose for younger populations, with infants receiving up to 42.9% higher doses than adults. Corresponding excess lifetime cancer risk followed a similar decreasing trend with age. These results demonstrate that adult-centric assessments may underestimate pediatric radiation burden and underscore the importance of integrating ICRP 116 age-specific dosimetry into environmental radiation protection frameworks.