Concentrations of natural 226Ra and 222Rn radioisotopes in the water from deep well intakes in the vicinity of Lódź

UNLABELLED: BACKGROUND. The towns of Zgierz, Ozorkow, Strykow and Glowno are located in the central part of Poland, 10 to 30 km to the north of Lodiź. Large surface water reservoirs are not available in that region, and the inhabitants of this region are supplied with drinking water from deep water sources. Literature data show that water from deep wells may contain various radionuclides, such as radium 226Ra or radon 222Rn, and their activity levels depend, among others, on the age of the geologic formation the water comes from. MATERIAL AND METHODS: An emanation technique employing a low-background system consisting of scintillation chamber with two photomultipliers operating in the coincidence arrangement was used to measure radium and radon concentrations. RESULTS: Radium-226 at levels above the detection level (9 Bq/m3) of the measurement method were not detected in any of the examined deep water sources. Water-solved radon-222 was detected in all tested samples. The measured activities were within the range of 1 kBq/m3 to 13 kBq/m3. CONCLUSIONS: Assuming the maximum concentration value, it is estimated that an annual dose received by the population drinking that water is 0.04 mSv, which is below the value of 0.1 mSv recommended by the World Health Organisation.