Evaluating radiological risk in semi-arid agriculture: Transfer factors of radionuclides in Moroccan food crops.

Abstract

Food crops can accumulate both natural and anthropogenic radionuclides, contributing to internal radiation exposure through ingestion. This study evaluates soil-to-plant transfer and the associated radiological risk in a semi-arid agricultural region of Meknes, Morocco. Results show that most radionuclides were below detection limits in edible crops, while 210Po and 40K exhibited measurable transfer, with transfer factors ranging from 0.005 to 0.018 and from 0.74 to 8.29, respectively. The estimated annual effective doses from crop consumption remained at or below the recommended public dose limit of 1 mSv/year, indicating a low overall radiological impact. Correlation analysis suggests that 40K transfer is mainly controlled by soil physicochemical properties and plant physiological demand, whereas 210Po exhibits limited and species-dependent behaviour. Although most lifetime cancer risk (LCR) values fall within acceptable international limits, the highest value recorded for long cucumbers slightly exceeds the recommended threshold (1.48 × 10-4), highlighting a potential localised concern. Hazard quotient values remained ≤1 for all crops, confirming the absence of significant non-carcinogenic risk. These findings provide region-specific data essential for improving radiological risk assessment and environmental monitoring in semi-arid agroecosystems. The results are particularly relevant for public protection and can support decision-making and management strategies in the context of routine monitoring as well as potential accidental radionuclide releases.