Baseline assessment of doses and risk due to natural radionuclides in edible biota of Domiasiat, Meghalaya, India

摘要

Radiation dose-risk assessment was carried out for cereal species Brassica compestris var. dichotoma, Oryza sativa var. Shalum1, Zea mays, Lactuca indica, Cumunis sativum, and Clocasia esculanta due to naturally available radionuclides ~(40)K, ~(238)U and ~(232)Th in Domiasiat area. The activity in biota and corresponding soil was measured by precipitation method using NaI(TI) detector. Transfer factor (TF) was for Oryza spp. (1.00E-01- ~(40)K, 8.76E-05- ~(232)Th, and 9.11E-05- ~(238)U), for Brassica spp. (5.39E-01- ~(40)K, 8.17E-04- ~(232)Th and 2.96E-04- ~(238)U) and for Zea spp. (3.41E-01- ~(40)K, 5.84E-05- ~(232)Th, 8.87E-05- ~(238)U) etc., respectively. A detailed physio-morphological study of the biota and extensive investigation of ecosystem was carried out for assessment. The data was modeled using FASSET for dose estimation and obtained total dose was 1.58E-04 μGy h ~(-1) in Oryza spp., 2.87E-04 μGy h ~(-1) Brassica spp. and 6.90E-03 μGy h ~(-1) in Zea spp. etc. The dose was compared with the UNSCEAR dataset for screening level dose for biota. Zea spp. was more susceptible for the chronic radiation exposure.