Activity concentrations of 226Ra and 228Ra in drilled well water in Finland

Abstract

The activity concentrations of (226)Ra and (228)Ra in drinking water were determined in water samples from 176 drilled wells. (226)Ra activity concentrations were in the range of <0.01-1.0 Bq l(-1) and (228)Ra activity concentrations in the range of <0.03-0.3 Bq l(-1). The mean activity concentration of (226)Ra and (228)Ra were 0.041 and 0.034 Bq l(-1), respectively. High radium activity concentrations in drinking water were rare. Only 2-4% of the drilled wells exceeded a (226)Ra concentration of 0.5 Bq l(-1) and 1-2% of the wells exceeded a (228)Ra concentration of 0.2 Bq l(-1). These are the activity concentrations that cause a 0.1 mSv annual effective dose for users of drinking water. The maximum annual effective doses from (226)Ra and (228)Ra for users of drilled wells were 0.21 mSv, and 0.16 mSv respectively. The elevated activity concentrations of (226)Ra and (228)Ra did not occur simultaneously in the same groundwaters and the correlation between (226)Ra and (228)Ra was small.

Radioactivity in drinking water: regulations, monitoring results and radiation protection issues

“…Very few examples are found of aqueducts contaminated by radium [63]. In Finland many investigations have been carried out even in recent times [32,64]. The problem of radium concerns only private wells and to a limited extent: 4% of the examined wells exceeded 500 mBq/l of 226 Ra and 1% exceeded 200 mBq/l of 228 Ra concentration.…”

Prevention measures against radiation exposure to radon in well waters: analysis of the present situation in Finland

“…After the project, dozens of removal units were in use in Finnish homes. In order to obtain longterm experiences of their operation, a follow-up project was initiated and the units were monitored until the end of 2002 (Vesterbacka et al 2003). At this time, a few hundred units had been installed and problems associated in their use had been recognized.…”

“…In the selection of the households, different types of water were covered, including iron-and manganese-rich water and water with a high content of organic carbon. Radon concentrations in raw water were 1,500 -7,400 Bq/l (Vesterbacka et al 2003). All GAC filters removed more that 90% of radon, and most of them nearly 100%.…”

“…Some equipment designed for iron and manganese removal can be partly filled with activated carbon and thus simultaneously removes iron, manganese and radon (Vesterbacka et al 2003). Iron and manganese removal units that are based on aeration-oxidation normally do not produce a sufficient amount of air to effectively strip radon and hence cannot be recommended for radon removal (Vesterbacka & Salonen 2008).…”

“…In terms of radiation dose, the most significant of these radionuclides is radon-222, which accounts for 71% of the effective dose received by users of drilled wells and 64% of that received by users of dug wells (Table 1). Apart from polonium-210, which accounts for 11% of the effective dose among users of drilled well water, doses from the rest of the nuclides are generally low (Vesterbacka et al 2005(Vesterbacka et al , 2006.…”