Major and trace elements in German bottled water, their regional distribution, and accordance with national and international standards

Abstract

The market for mineral water has been growing steadily over the last few years. Germany is the country with the highest number of bottled mineral water brands (908 bottled water samples from 502 wells/brands were analyzed). The per capita consumption of mineral water in Germany in 2003 was 129 L. A wide range of values of one to seven orders of magnitude was determined for 71 elements in the bottled water samples analyzed by ICP-QMS, ICP-AES, IC, titration, photometric, conductometric and potentiometric methods. A comparison of the element concentrations and the legal limits for both bottled and tap water (EU, Germany, US EPA, WHO) shows that only 70% of the 908 mineral water samples fulfill the German and EU drinking water (i.e., tap water) regulations for all parameters (not including pH) for which action levels are defined. Nearly 5% of the bottled water samples not fulfill the German and EU regulations for mineral and table water. Comparison of our results with the current German and European action levels for mineral and table water shows that only 42 of the bottled water samples exceed the limits for one or more of the following elements: arsenic, nitrate, nitrite, manganese, nickel and barium concentrations. Ten of the bottled water samples contain uranium concentrations above the 10 μg/L recommended limit. A selection of existing water quality classification systems was used in order to characterize the different mineral water types. For example, the relationships among selected variables were examined using Durov, Piper and van Wirdum diagrams. Univariate and multivariate (component analysis) statistical methods were used to analyze the data to characterize the bottled water from the different well regions of Germany. Maps of the element distributions are presented. Most of the elements show a clear regional dependency. The bottled water shows conspicuous geochemical influences by the limestone aquifers of the Muschelkalk (Middle Triassic), the sandstone aquifers of the Bunter and Keuper (Lower and Upper Triassic), the gypsum of the Keuper, and the aquifers in gneiss basement rocks.