A radiation dose assessment exercise was carried out for the edible biota Solanum nigrum, Carica papaya, Raphnus sativum and Phaseolus domesticus due to naturally available radionuclides 40 K, 238 U and 232 Th in the Domiasiat area in Meghalaya, India. The concentration of radionuclides in biota and corresponding soil was measured by the NaI(Tl) detector having a minimum detection limit (efficiency, 32.4 %) and machine counting time of 3000 s. The obtained transfer factor for 40 K was 0.3061,

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... 7163, 0.1988 and 0.1279, for 232 Th 0.0003, 2.22E205, 2.71E205 and 3.45E205 and for 238 U 1.46E205, 9.73E205, 1.46E205 and 3.11E205 (ratio) in each biota, respectively. The detailed physiological and morphological study of the biota was carried out. The point source dose distribution (source$target) hypothesis was applied for the radiation absorbed fraction. The generated data were modelled using FASSET and obtained un-weighted total dose was 1.78E204, 6.84E203, 8.46E203 and 1.73E204mGy h 21 , respectively, finally compared with the IAEA and UNSCEAR data set for screening level dose risk assessment.