Soil-to-plant transfer of ²²⁶Ra and radiological risk from cassava consumption in a tropical agroecosystem: a multi-matrix assessment from Ecuador

This study evaluated the activity concentrations of ²²⁶Ra in cassava pulp, peel, and derived starch cultivated in three production sectors of Chone, Ecuador, and assessed soil-to-plant transfer and associated dietary exposure. Results show pronounced sector-dependent variability in radionuclide distribution, with consistently lower ²²⁶Ra levels in starch relative to raw plant fractions. Estimated ingestion doses for both children and adults were negligible and well below international reference values. These findings provide the first multi-matrix baseline for ²²⁶Ra transfer in cassava under tropical Ecuadorian conditions and support site-specific radiological risk assessments.