Natural radioactivity in groundwater – a review

Abstract

The issue of natural radioactivity in groundwater is reviewed, with emphasis on those radioisotopes which contribute in a significant way to the overall effective dose received by members of the public due to the intake of drinking water originating from groundwater systems. The term 'natural radioactivity' is used in this context to cover all radioactivity present in the environment, including man-made (anthropogenic) radioactivity. Comprehensive discussion of radiological aspects of the presence of natural radionuclides in groundwater, including an overview of current regulations dealing with radioactivity in drinking water, is provided. The presented data indicate that thorough assessments of the committed doses resulting from the presence of natural radioactivity in groundwater are needed, particularly when such water is envisaged for regular intake by infants. They should be based on a precise determination of radioactivity concentration levels of the whole suite of radionuclides, including characterisation of their temporal variability. Equally important is a realistic assessment of water intake values for specific age groups. Only such an evaluation may provide the basis for possible remedial actions.

222Rn and 226Ra activity concentrations in groundwaters of southern Poland: new data and selected genetic relations

“…222 Rn, 226 Ra and 228 Ra, play the key role when it comes to radioactive properties of groundwaters [23]. Because of this, any information concerning concentrations of these radionuclides in groundwater is important from the radiological point of view.…”

Natural uranium isotopes and 226Ra in surface and groundwater from a basin of a semiarid region in Brazil

“…In general, these results suggest that 226 Ra activity concentration is partly supported by the decay of U and that geochemical conditions influencing the precipitation/dissolution and sorption processes leads to increase the differences in activity concentrations between Ra and U. For example, the presence of carbonates at pH higher than 7.5 favor the uranium dissolution and mobilization [41], conditions that are present in the studied groundwater [30].…”

Occurrence of 222Rn and 226,228Ra in underground water and 222Rn in soil and their mutual correlations for underground water supplies in southern Greater Poland

“…An alternative approach to evaluate the ID is to compare the activity concentration of the main radionuclides present in water with its proposed derived concentrations for radioactivity in water, whose intake corresponds to the annual effective dose of 0.1 mSv. Among natural radionuclides present in underground water, 40 K and uranium isotopes can be easily determined by chemical methods, and their concentrations in these water samples lead to internal doses in the range below 1 µSv (Dinh Chau et al 2011 ; UNSCEAR 2000 ). The value of the proposed derived concentration for 228 Ra is lower (0.2 Bq dm −3 ) than that for 226 Ra (0.5 Bq dm −3 ).…”