Study of the reduction in the time of counting in spectrometric analysis using HPGe detector for samples of fresh organic foods

The quantification of natural radionuclides within environmental matrices is commonly executed via gamma spectrometry, employing HPGe detector. Variability in counting times is reported in the literature, often predicated on empirical knowledge. This study aims to estimate a reduction in counting time in the process of analyzing activity concentration of ⁴⁰K radionuclide, based on reducing the percentage variation of their uncertainties, in some fresh and frozen organic vegetables, grown in an environmental conservation unit. For each sample, 10 count measurements were taken at regular intervals of 3600 s over a period of 36,000 s using the HPGe detector and the Genie 2000 data acquisition software. The background spectrum was obtained at the same time intervals and with the same sample geometry. Efficiency curves and self-attenuation corrections were performed using the LabSOCS software. Considering the counting times 25,200 s and 36,000 s, the determined ⁴⁰K activity concentration (Bq.kg⁻¹) for lady's finger banana, cabbage and carrot were (107 ± 16.49; 109 ± 16.35), (79 ± 12.77; 81 ± 12.62) and (100 ± 15.44; 102 ± 15.36), respectively. The activity concentrate uncertainty starts to vary slightly and began to stabilize from 25,200s onwards. The results indicate that considering the employed methodology, extending the counting time for fresh and frozen organic foods would not yield a significant advantage over reducing the detector operation time.