Natural radioactivity in Indian vegetation samples

Background: Vegetation (food stuff) is grown in soil that contains many radioactive elements such as 238U (uranium), 232Th (thorium) and 40K (potassium), which may get deposited either due to radioactive fallout or/and by absorption from the soil and can pose serious health hazards. Materials and Methods: Natural radioactivity, radiological hazards and annual effective dose assessment was carried out in vegetation samples (vegetables, cereals and fruits) collected from fields and market. Gamma spectrometry using HPGe detector was used. Results: The measured specific activity concentration of 238U (uranium), 232Th (thorium) and 40K (potassium) varied from 10.25 ± 0.94 Bq/kg to 29.13 ± 0.69 Bq/kg, 22.20 ± 2.46 Bq/kg to 58.21 ± 1.15 Bq/kg, and 1158.4 ± 26.05 Bq/kg to 1962.2 ± 18.17 Bq/kg respectively in various vegetable and cereal samples and varied from 2.5 ± 0.16 Bq/kg to 9.8 ± 0.15 Bq/kg, 7.4 ± 1.24 Bq/kg to 18.4 ± 1.39 Bq/kg, and 287.13 ± 11.23 Bq/kg to 815.72 ± 12.50 Bq/kg respectively in various fruit samples studied in the present work. From these values, hazard indices, the minimum and maximum values of absorbed dose and indoor and outdoor annual effective doses were calculated for various samples used in the present investigation. Conclusion: The various values obtained were found to be within the recommended limits. The absorbed dose and annual effective dose for the vegetable and cereal samples in which fertilizers were used to enhance the crop yield were higher than that in fruit samples.