Abstract
The specific activity of U-238 and Th-232, as well as K-40 radionuclides, in twenty-nine investigated medicinal herbs used in Egypt has been measured using a high-purity germanium (HP Ge) detector. The measured values ranged from the BDL to 20.71 ± 1.52 with a mean of 7.25 ± 0.54 (Bq kg
−1
) for uranium-238, from the BDL to 29.35 ± 1.33 with a mean of 7.78 ± 0.633 (Bq kg
−1
) for thorium-232, and from 172 ± 5.85 to 1181.2 ± 25.5 with a mean of 471.4 ± 11.33 (Bq kg
−1
) for potassium-40. Individual herbs with the highest activity levels were found to be 20.71 ± 1.52 (Bq kg
−1
) for uranium-238 (H4, Thyme herb), 29.35 ± 1.33 (Bq kg
−1
) for thorium-232 (H20, Cinnamon), and 1181.2 ± 25.5 (Bq kg
−1
) for potassium-40 (H24, Worm-wood). (
AACED
) Ingestion-related effective doses over the course of a year of uranium-238 and thorium-232, as well as potassium-40 estimated from measured activity concentrations, are 0.002304 ± 0.00009 (minimum), 0.50869 ± 0.0002 (maximum), and 0.0373 ± 0.0004 (average)(mSv/yr). Radium equivalent activity (
R
aeq), annual gonadal dose equivalent (
AGDE
), absorbed gamma dose rate (
D
outdoor
,
D
indoor
), gamma representative level index (I), annual effective dose (
AED
total), external and internal hazard index (
H
ex
,
H
in
), and excess lifetime cancer risk were determined in medicinal plants (
ELCR
). The radiological hazards assessment revealed that the investigated plant species have natural radioactivity levels that are well within the internationally recommended limit. This is the first time that the natural radioactivity of therapeutic plants has been measured in Egypt. In addition, no artificial radionuclide (for example, 137Cs) was discovered in any of the samples. Therefore, the current findings are intended to serve as the foundation for establishing a standard safety and guideline for using these therapeutic plants in Egypt.