A radiological study of radon concentration in commonly used herbal medical plants and its probable environmental and public health impacts.

Natural radon in medicinal plants represents a potential source of internal radiation exposure. This study aims to assess radon activity concentration and the related radiation hazard indices in 65 commonly consumed medicinal plants. The solid-state detector (CR-39) measured radon levels using the sealed-can technique. The average radon concentration in the confined air above the samples was 25.07 ± 0.45 Bq m- 3, whereas the average radon level within the plant matrices was 1073.68 ± 21.34 Bq m- 3, indicating higher levels and intrinsic radionuclide content. The average radium activity was 0.201 ± 0.003 Bq kg- 1, remaining below global limits of 35 Bq kg- 1, and showed a strong positive correlation with radon accumulation (R2 = 0.76). The average annual effective dose from radon ingestion was 0.021 ± 0.000 µSv y- 1 for low consumption, increasing proportionally to 0.205 ± 0.003 µSv y- 1 under high-consumption scenarios. These values are below the recommended dose limit of 1 mSv y- 1. The average excess lifetime cancer risk values (0.079 ± 0.001 × 10- 6 - 0.790 ± 0.013 × 10- 6) were lower than safety limits of 2.9 × 10-4. The findings indicate that regular consumption of the investigated medical plants is unlikely to present a significant environmental health risk.