Potassium concentrations and annual effective dose of the customary food stuffs in Mexico

Measurement of radionuclides concentration in foodstuffs allows to assess the intake’s assimilated dose. This contributes at least one-eighth of the mean annual effective dose due to natural sources. Among the trace elements in foodstuff, potassium is one of the most important elements. It is a well-known essential element and it occurs all over the earth. Three of the most customary consumed foodstuffs in Mexico since pre-Hispanic time (by all social classes) are the following: bean, chili and corn meal (“tortillas”). They were analyzed by γ-spectrometry in order to determine 40K activity concentration, the derived annual effective dose, and the K mass fraction (%). Results show that the mean activity concentration of 40K, annual effective dose and K mass fraction (%) are as follow: 901 ± 90 Bq kg−1, 37.2 ± 3.7 μSv a−1 and 2.84 ± 0.27 % for chili; 510 ± 10 Bq kg−1, 27.5 ± 0.5 μSv a−1 and 1.60 ± 0.04 % for bean; and, 90 ± 30 Bq kg−1, 58.1 ± 19.4 μSv a−1 and 0.27 ± 0.089 % for corn meal, “masa”. The total effective dose intake from these typical foodstuffs is about 0.122 ± 15.6 mSv a−1in Mexico’s urban zones.