Asbestos concentrations in drinking water. Asbestos cement pipes and geogenic sources in Austria

Sources of asbestos in drinking water may be natural deposits or the use of asbestos cement for water distribution. 50 water samples were selected in Austria to detect fibre contamination from either geology or asbestos cement by comparison with control areas and by comparison of raw and treated water. Standardized EPA/BGA methodology with transmission electron microscopy, energy dispersive X-ray analysis and selected area electron diffraction was used to quantify concentrations of different sized amphibole and chrysotile fibres. In 10 areas with asbestos deposits and in 14 areas with use of asbestos cement pipes asbestos concentrations in drinking water were low and not significantly different from 6 control areas (median 32,000 total asbestos fibres per litre). The relative highest concentration was found in an area with natural deposits at the source of the water supply (190,000 per litre). In areas without natural deposits the increase of asbestos concentrations from origin to consumer of water was not significant and unrelated to water aggressiveness, age and length of asbestos cement pipes. This could be mainly due to the fact that in areas with aggressive water asbestos cement pipes have been coated in Austria. A sample from a cistern, however, showed considerable asbestos contamination and raises concern about the use of surface water for room air humidification.