Chemical composition of bottled mineral waters in Estonia

Five commercially available in Estonia brands of bottled water have been analysed for 59 chemical elements by ICP-QMS and ICP-AES techniques to assess the quality of domestic mineral waters in scope of the European Groundwater Geochemistry Project initiated by the Geochemistry Expert Group of EuroGeoSurveys. Contents of 9 cations and anions, pH and electrical conductivity (EC) were measured in the bottled mineral waters by IC, titration and photometric methods. The data showed a significant difference between natural undiluted mineral water (Värska Originaal) characterised by the highest values of pH, EC and majority of trace elements studied, and other domestic waters sold in Estonia.

The results obtained were compared with the drinking water standards (US EPA, EU and Estonian Permitted Limits). Despite of the wide range of trace element concentrations in all Estonian brands of commercially sold waters the estimated values are generally within defined maximum concentrations allowed for drinking water.

The B concentration assessed in the Värska Originaal water above the maximal permitted values defined as 1 mg/L is a result of long residence time of water due to slow water exchange in the water-bearing Ordovician–Cambrian rocks.

Differences in chemical composition of the bottled waters are linked to host rocks geology in the studied area.