Microbiological quality of carbonated drinking water produced with in-home carbonation systems

In 12% of tap-water samples, coliforms could be detected. On the other hand, in 20 of 52 carbonated waters (39%), coliforms as indicators of water pollution were found. By means of fecal streptococci and Pseudomonas aeruginosa, it was possible to establish additional contamination not involving E. coli or coliforms alone. Analysis revealed that, in addition to contaminated tap water, a bacterial biofilm on the inner surface of the re-usable bottles had a predominant influence on the microbiological quality of the carbonated water.