Radiological and chemical monitoring of Dikili geothermal waters, Western Turkey

highlights•This paper analyses radiological and chemical contents of thermal waters located in Dikili geothermal area of Turkey.•The quality of waters is evaluated according to national and international recommendations.•The chemical–physical parameters do not exceed the maximum limit of contamination for analysed waters

Naturally occurring Radionuclides such as 226Ra and 222Rn as well as the major dissolved ions were investigated in the four thermal springs from Dikili Geothermal Area, Western Turkey. It was observed that 222Rn concentrations vary from 0.3 to 31 Bql−1 with an average value of 8.2 Bql−1, while the 226Ra activities range from 0.10 to 1.2 Bql−1 with a mean value of 0.495 Bql−1. A direct correlation was determined between radon and radium activities which indicates their parent–child relationship. The annual effective doses ranged from 0.58 to 3.06 µSvy−1 with an average 1.75 for radon and vary from 4.88 to 8.58 µSvy−1 with an average value of 6.53 µSvy−1 for radium and all are well below 100 µSvy−1 recommended by WHO. The chemical analyses of water samples show that Na+ and Cl− ions mainly dominate the chemistry of waters. Due to their chemical characteristics, the springs were placed in the Water Quality Class 1 or 2 according to Turkish Environmental Regulations for Water Pollution Control. On the other hand, no significant correlations was found between the physic–chemical parameters and investigated radionuclides.