In this study, radioactive and heavy metal contaminations in sediments and waters of Bakircay River in Western Turkey were investigated to determine their pollution potential. The radium concentrations in the water samples were measured using the collector-chamber method. The radioactivities of K-40, Ra-226 and Th-232 in sediments and soils were found to be 45.30 to 839.19 Bq kg(-1), 35.26 to 160.57 Bq kg(-1) and 1.86 to 131.49 Bq kg(-1), respectively. The activity of Ra-226 in the water samples ranged from 0.09 to 0.36 Bq/L To determine the radiological hazard of natural radioactivity in the samples, the external terrestrial gamma dose rate in air (n Gyh(-1)), annual effective dose rate (mSv y(-1)), radium equivalent activity (Bq kg(-1)) were calculated and compared with internationally recommended values. (C) 2012 Elsevier Ltd. All rights reserved.