Measurements of some radionuclides in coffee samples using gamma-ray spectrometry and evaluating radiological health risk to the Turkish public

Abstract

The current research aims to assess the radioactivity levels and radiological health risks of 28 coffee samples from 21 assorted brands obtained from different provinces of Turkey. The activity concentrations of natural radionuclides (226Ra, 232Th and 40K) and artificial radionuclide 137Cs in the samples were quantified using the high-resolution gamma ray spectroscopy technique with an HPGe detector. 137Cs could not be found in any of the samples. The activity concentrations in all coffee samples were found in the range of <MDA–2.93 Bq kg−1 with an average of 1.24 Bq kg−1 for 226Ra, <MDA–3.06 Bq kg−1 with an average of 1.51 Bq kg−1 for 232Th and 433.67–538.69 Bq kg−1 with an average of 496.24 Bq kg−1 for 40K. Radiological parameters such as annual intake of radioactivity (Yint), committed effective dose (Deff), threshold consumption rate (DIthresh), and excess lifetime cancer risk (ELCR) were evaluated to estimate human radiological risk in the coffee samples. The total committed effective dose to an individual due to the consumption of each coffee sample was less than the dose limit of 290 μSv y−1 suggested by UNSCEAR. The lowest threshold consumption rate (kg y−1 or g d−1) calculated in all coffee samples was higher than the amount of coffee consumed per year (kg y−1) and the amount of coffee consumed at the daily normal level (g d−1, cups d−1). The total lifetime cancer risks from ingestion of the sampled coffees were estimated to be less than the advised safety limit (10−3). Based on the obtained results, none of the coffee samples analysed in the present study constitute a possible radiological risk for public health. Pearson’s correlation coefficient analysis (PCCA) and discriminant analysis (DA) were used to present the relationships between the radionuclides and distinguish the group members, respectively.