J. Environ. Radioartivify, zyxwvutsrqponmlkjihgfedcbaZYXWV Vol. 28 No. 2. pp. 113-139. 1995 Copyright @ 1995 Elsevier Science Limited Printed in Ireland. All rights reserved ELSEVIER 0265-93 IX/95 $9.50 + 0.00 0265-931X(94)00054-9 Distribution of some Natural and Artificial Radionuclides in the Environment of Coastal Karnataka of South India Y. Narayana, A. P. Radhakrishna, H. M. Somashekarappa, N. Karunakara, K. M. Balakrishna & K. Siddappa Department of Physics, Mangalore University, Mangalagangotri 574199, India (Received for publication 22 September 1994) ABSTRACT Coastal Karnataka, which is an important region of the south-west coast of India, is poised to become a region of major industrial activity with the construction of nuclear and thermal power stations, oil refineries and petrochemical complexes. This is in addition to existing chemical and fertilizer factories and a host of other industries. Systematic studies on radiation levels and radionuclide distributions in the environment of this region were undertaken to provide baseline data on the radiation levels for future assessment of the impact of these industrial activities and to throw light on the basic aspects of transportation of radionuclides in the environ- ment and their uptake by vegetation species. The activities of 4oK, 226Ra, 210Po, “‘Pb, 228Ra, 137Cs and 9oSr were determined in a number of envir- onmental samples of the region by employing well established nuclear techniques and standard radiochemical methods. The internal dose to the population of the region from ingestion of different radionuclides was esti- mated. The results of these systematic investigations, which form the zyxwvutsrqponml first ever report on the radionuclide distribution of coastal Karnataka, are presented and discussed in this paper. INTRODUCTION Studies on radiation levels and radionuclide distribution in the environ- ment are important for several reasons. Baseline information on radiation levels and radionuclide distribution in the environment is essential in 113