Performance Evaluation of an Italian Reference Method, the ISO Reference Method and a Chromogenic Rapid Method for the Detection of E. coli and Coliforms in Bottled Water
Bottled water can be contaminated by coliforms and/or Escherichia coli (E. coli). These bacteria are considered as indicators of faecal pollution, and their detection in bottled water indicates the potential contamination by pathogenic enteric microorganisms. In recent decades, different methods were developed for the detection of coliforms and E. coli in drinking water and in bottled water including mineral water. Since 1976, the Italian regulation has defined microbiological methods to evaluate microbiological characteristics of mineral waters. Three different methods for the detection of coliforms and E. coli in bottled water were compared in this study: the Italian reference method, according to the “Italian Ministerial Rule,” the ISO 9308–1:2002 method, and a new rapid method. The results have demonstrated that the ISO method 9308–1:2002 and the new rapid method are as sensitive and specific as Italian reference method, and that both could be used to evaluate the contamination level of coliform and E. coli in drinking water and in bottled water including mineral water.
KeywordsBottled water Escherichia coli Coliform Indicator microorganisms Microbiological methods
We acknowledge helpful comments from Dr. Nigel Cook, DEFRA Central Science Laboratory, UK.
Conflict of Interest
Simona Di Pasquale has no conflict of interest. Dario De Medici has no conflict of interest. Our article does not contain any studies with human or animal subjects.
- Anonymous (1993) Metodi di analisi per la valutazione delle caratteristiche microbiologiche e di composizione delle acque minerali naturali e modalità per i relativi prelevamenti dei campioni. Gazzetta Italiana della Repubblica Italiana, Serie Generale 14(del 19-1-1993):30–31Google Scholar
- Anonymous (2000) ISO 9308–1:2000 water quality—detection and enumeration of Escherichia coli and coliform bacteria. Part 1. Membrane filtration. International Organization for Standardization, GenevaGoogle Scholar
- Anonymous (2009a) European union: directive 2009/54/EC of the European parliament and of the council of 18 june 2009 on the exploitation and marketing of natural mineral water. Off J Eur Union L164:45–58Google Scholar
- Anonymous (2009b) European union: directive 2009/54/EC of the European parliament and of the council on the exploitation and marketing of natural mineral waters. Off J Eur Union L164:45–58Google Scholar
- Anonymous (2011) Microbiology of food and animal feeding stuffs—protocol for the validation of alternative methods - Amended 1 (ISO 16140:2003/AMD 1:2011). European Commitee for Standardization, BrusselsGoogle Scholar
- Briancesco R (2005) Microbial indicators and fresh water quality assessment. Ann Ist Super Sanita 41:353–358Google Scholar
- EFBW (2012) Bottle water facts. European Federation of Bottled Water http://efbw.eu/bwf.php?classement=07. Accessed 16 Jan 2014
- Food and Drug Administration (2009) Beverages: bottled water. Fed Regist 74:25651–25665Google Scholar
- Fricker CR, DeSarno M, Warden PS, Eldred BJ (2008) False-negative beta-D-glucuronidase reactions in membrane lactose glucuronide agar medium used for the simultaneous detection of coliforms and Escherichia coli from water. Lett Appl Microbiol 47:539–542. doi: 10.1111/j.1472-765X.2008.02453.x CrossRefGoogle Scholar
- Havelaar A, Blumenthal S, Strauss M, Kay D, Bartram J (2001) Guidelines: the current position. In: Fewtrell L, Bartram J (eds) Water quality: guidelines, standards and health. World Health Organization and IWA Publishing, LondonGoogle Scholar
- Ingram M (1977) The significance of the index and indicator organisms in foods. In: Tenth Intl Symposium of the IUMS Committee on Food Microbiology and Hygiene, Szczecin, Poland, Sept 5–10 1977Google Scholar