BGS carried out a survey of the inorganic chemistry of bottled natural mineral waters and spring waters from across the British Isles. We analysed 85 samples from 67 groundwater sources, from a diverse range of aquifer rock types. Analyses included the major ions and a wide range of trace elements.
The well head at the base of The Slopes, Buxton, England, provides a free public source of spring water. The same water is bottled and sold as Buxton Natural Mineral Water. © Ian Capper.
Background
Try to find out the chemistry of mains water supplied to your home tap and the chances are you will come across a comprehensive list of analytes, at least in summary form, on the web. The chemistry of bottled water is less easy to find and, although most manufacturers supply representative major ion data on the labels, trace elements are not commonly included.
We set about analysing the major ions and a range of trace elements in a selection of still British bottled waters, available from retail outlets across the British Isles.
Research findings
Results of the study showed that concentrations of the inorganic constituents analysed were well within the limits for compliance with European and national standards for bottled waters. A small number of samples had relatively high uranium concentrations (10 to 13 μg/L), though none exceeded the current provisional World Health Organization (WHO) guideline value for uranium in drinking water, which is 30 μg/L. No European limit currently exists for uranium in bottled water.
Concentrations of antimony were higher in water samples contained in PET (plastic) bottles compared to those contained in glass and compared to raw groundwater samples from the corresponding aquifers. The increases are likely derived from contamination from the PET bottles. In no cases, however, did the concentrations approach the limit for antimony in natural mineral waters or water intended for human consumption, which is 5 μg/L.
In comparison with raw groundwaters from equivalent aquifers in Britain, the bottled waters had lower overall concentrations of aluminium, cadmium, copper, iron, manganese, lead and zinc, consistent with loss by processing before bottling; for example, by aeration, settling or filtration. The choice of material used for pipework at the bottling plants may be an additional factor.
The Magnesia Well, Harrogate, England. Harrogate has 88 springs, one of which is bottled as Harrogate Spring Water. © habiloid.
Results suggest that, although the major ions in the bottled waters appear for the most part representative of the groundwater in their host aquifers, many of the trace elements appear to have been modified significantly from natural compositions underground as a result of processing.
Further information
Smedley, P, L. 2010. A survey of the inorganic chemistry of bottled mineral waters from the British Isles. Applied Geochemistry, Vol. 25, 1872–1888. DOI: https://doi.org/10.1016/j.apgeochem.2010.10.003
Contact
Please contact Pauline Smedley for further information.