Measurement Of Activity Concentrations Of 226Ra, 232Th, 40K And 137Cs In Some Common Spices Consumed By Inhabitants In Accra Metropolis, Ghana

Abstract

A spice is a vegetable substance of indigenous or exotic origin which is or has a hot, pigment taste, used to enhance taste of foods or to add to them the stimulant ingredients contained in them. Knowledge of radioactivity levels in human diet is of particular concern for the estimation of possible radiological hazards to human health. In this study, the radioactivity concentrations of 226 Ra, 232 Th, 40 K and 137 Cs in some selected natural and processed spices of different brands in the Madina District of Accra Metropolis were determined and the ingested doses via food consumption were also assessed using gamma spectrometry. The average activity concentration of 226 Ra, 232 Th, 40 K and 137 Cs in the natural spices were 0.81 ± 0.2 BqKg -1 , 0.98 ± 0.4 BqKg -1 , 2.19 ± 0.9 BqKg -1 and 0.06 ± 0.01 BqKg -1 respectively. For the processed spices, the average activity concentration of 226 Ra, 232 Th, 40 K and 137 Cs were 0.18 ± 0.1 BqKg -1 , 0.3 ± 0.1 BqKg -1 , 1.3 ± 0.8 BqKg -1 and 0.02 ± 0.01 BqKg -1 respectively. The levels of 137 Cs observed in the samples are within the range of 'background' concentrations. The estimated total annual effective dose received from 226 Ra, 232 Th and 137 Cs, due to consumption of natural (fresh) and processed spices by the inhabitants of Madina in the Accra metropolis was 8.47 µSvy -1 and this is far below the average radiation dose of 0.29 mSvy -1 received per caput worldwide due to ingestion of natural radionuclides provided in UNSCEAR (2000) report. The results indicate insignificant radiologi - cal health hazard to the public due to the consumption of spices via foods. 226 Ra; 232 Th; 40 K; 137 Cs; Spices; Hpge; Effective Dose.