Radionuclides and heavy metals concentrations in traditional medicinal plants used in Saudi Arabia

Traditional medicinal plants are widely used for the treatment of various diseases in Saudi Arabia. Knowledge of chemical composition of these materials is important as it pertains to health. The activity concentrations of Th-232, Ra-226 and K-40 were measured in twenty-six medicinal plant samples purchased from different local Saudi markets using y- spectrometry with a NaI[Tl] detector. They ranged between 0.50 +/- 0.04 to 13.72 +/- 1.15 Bq kg(-1), 0.45 +/- 0.04 to 12.73 +/- 1.02 Bq kg(-1) and 7.00 +/- 0.50 to 327.06 +/- 11.0 Bq kg(-1), respectively. The radium equivalent activity and absorbed dose rate in the studied samples varied from 1.21 to 54.45 Bq kg(-1) and from 0.55 to 28.24 nGyh(-1), respectively. Intake of radionuclides in samples was insignificant. Consequently, these samples were considered safe in terms of radiological health hazards. The concentration of six heavy metals: Cd, Pb, As, Cu, Mn and Zn were monitored by inductively coupled plasma optical emission and some of them were found above permissible limit.