Modeling and field trials optimize crop-based phytoremediation of soils contaminated with radioactive strontium and cesium

When agricultural soils are contaminated by strontium-90 ( 90 Sr) and cesium-137 ( 137 Cs), remediation is needed to ensure effective decontamination and food safety. This study developed an integrated phytoremediation framework for 90 Sr- and 137 Cs-contaminated soils in Southern China, combining field trials with a novel kinetic model that accounts for soil-to-plant transfer, species-specific sensitivity distributions, and internal human dosimetry. Field trials were conducted to generate sufficient soil–plant transfer data, which were used to parameterize and validate the kinetic model describing radionuclide migration within the soil–plant–human system. Our work is among the first to couple field-based phytoextraction data with organ-specific dose modeling. The framework enables predictive evaluation of radionuclide transfer and dose, supporting optimized crop rotations in radiologically-impacted farmland. Field trials revealed significant soil contamination, with 90 Sr activity concentrations ranging from 5.50 × 10 2 to 6.59 × 10 2 Bq·kg −1 , and 137 Cs levels from 3.91 × 10 2 to 6.16 × 10 2 Bq·kg −1 . The study found that hyperaccumulating leafy vegetables, such as cabbage and spinach, exhibited high transfer factors for 90 Sr (up to 1.47) and 137 Cs (up to 3.90), making them effective for initial soil decontamination. Low-uptake crops, such as corn and wheat, were identified as suitable for long-term sustainable cultivation, as they exhibit minimal radionuclide transfer to edible parts, thereby reducing foodborne health risks. Predicted internal effective doses from crop consumption were calculated for male and female populations, with reductions being up to 70 % in model-predicted internal radiation exposure under optimized crop selection. • Field trials showed distinct crop-specific uptake of 90 Sr and 137 Cs in contaminated soils. • A novel soil–plant–human kinetic model linked phytoremediation to human dosimetry. • Hyperaccumulating leafy vegetables were effective for initial soil decontamination. • Low-uptake cereals ensured safe long-term farming with minimal radionuclide transfer. • Optimized crop strategy reduced internal radiation exposure in humans by over 70 %.