Measurement of natural and artificial radioactivity in powdered milk consumed in Jordan and estimates of the corresponding annual effective dose

The activity concentrations of (40)K, (226)Ra, (228)Ra and (137)Cs were measured for 14 brands of the powdered milk consumed in Jordan, which are imported from various regions around the world. The activity concentrations of (40)K were found not to vary greatly from one brand to the other with an average of 348 +/- 26 Bq kg(-1). However, the activity concentrations of (137)Cs revealed a geographical distribution being: (i) undetected in any of the samples from Argentina, (ii) uniformly distributed in samples from Europe with an average of 0.43 +/- 0.05 Bq kg(-1), and (iii) widely varying in samples from New Zealand (from being not detected (ND) to 1.55 Bq kg(-1)). (226)Ra and (228)Ra were measured above the detection limits in five brands only and displayed relatively low activity concentrations of 0.50-2.14 and 0.78-1.28 Bq kg(-1) for (226)Ra and (228)Ra, respectively. The total average annual effective doses due to intake of (40)K, (226)Ra, (228)Ra and (137)Cs from the ingestion of the powdered milk for infants, children and adults were estimated to be (in microSv): 332, 138 and 43, respectively. These results indicate no significant radiation dose to the public.