238U and 232Th concentrations in various foodstuffs in Morocco and resulting radiation doses to the members of the public

Uranium (U-238) and thorium (Th-232) concentrations were measured in different foods widely consumed in Morocco by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). Data obtained were compared to those obtained by using isotope dilution mass spectrometry (IDMS). Total daily intakes of U-238 and Th-232 for a typical food basket were estimated to be 1.3 +/- 0.1 mBq d(-1) and 0.98 +/- 0.08 mBq d(-1), 1.4 +/- 0.1 mBq d(-1) and 1.06 +/- 0.08 mBq d(-1), 1.7 +/- 0.1 mBq d(-1) and 1.26 +/- 0.08 mBq d(-1) and 2.0 +/- 0.1 mBq d(-1) and 1.5 +/- 0.1 Bq d(-1) for the 2-7 years, 7-12 years, 12-17 years and adult's age groups, respectively. Alpha-activities due to annual U-238 and Th-232 intakes from the ingestion of the studied foodstuffs were determined in different organs and tissues of the human body of members of the public by using the ICRP gastrointestinal tract and systemic part models for these radionuclides. Committed equivalent doses due to annual intakes of U-238 and Th-232 were evaluated in the human body organs and tissues for different age groups of the Moroccan population by exploiting data obtained for alpha-doses deposited by 1 Bq of U-238 and 1 Bq or Th-232 in the considered human organs and tissues. The influence of the mass of the target tissue and activities due to U-238 and Th-232 on the committed equivalent doses due to annual intakes of these radionuclides in the organs and tissues of the human body was studied.