Abstract
Thirty-three samples of powdered milk and thirteen samples of liquid milk (mostly imported from several countries) were collected from the local market in Saudi Arabia to measure the activity concentrations of artificial and natural radionuclides and evaluate the safety of milk for humans. Spectrometric analysis using the HPGe detector was performed. The results show that the activity concentration of K-40 in powdered milk ranged between 130 +/- 7 and 595 +/- 32 Bq kg(-1) (average 285 +/- 29 Bq kg(-1)), and that of Cs-137 ranged between 0.05 +/- 0.02 and 1.3 +/- 0.2 Bq kg(-1) in powder milk. In liquid milk, the activity concentration of K-40 ranged between 40 +/- 2 and 98 +/- 5 Bq L-1 (average 66 +/- 4 Bq L-1), and that of Cs-137 was 0.12 +/- 0.03 Bq L-1. The annual internal dose for K-40 and Cs-137 was calculated, and it is lower than the regulated dose.