Water microbiological

Chapelle, F. H., 2001, Ground-Water Microbiology and Geochemistry, 2nd ed. Wiley, New York. 

Chapelle FH (1993) Ground water microbiology and geochemistry. Wiley, New York... 

Unfortunately, much of the information available from original manufacturers of biocides is often unreliable or unrealistic when applied to field conditions, and some manufacturers may misleadingly provide documentation indicating that their particular biocide is a panacea for all cooling water microbiological ills, which patently cannot be the case. 

Kenzaka, T., N. Yamaguchi, K. Tani, and M. Nasu. 1998. rRNA-targeted fluorescent in situ hybridization analysis of bacterial community structure in river water. Microbiology 144 2085-2093. 

Experiment 14 Biochemical Oxygen Demand, Water Microbiology... 

Flexibilization of the scope of accreditation an important asset for food and water microbiology laboratories... 

Keywords Accreditation Food and water microbiology Validation Type of tests... 

As regards food and water microbiology, current outbreaks in Europe have made apparent the necessity for official inspection agencies or ministry departments and for food industries or water agencies to get laboratories accredited quickly to perform tests in accordance with new test parameters, or to apply current methods to new ranges of food products. Accredited laboratories must be able to develop and validate new methods, or to derive methods from standards. Official recognition of these new test methods or their official incorporation into the scope of accreditation takes a long time, and audits are required for validation of these test methods. 

Accreditation with flexible scope allows laboratories who receive requests for evaluation and analysis to quickly provide customers with a service adapted to their actual needs (Fig. 2), and provides food and water microbiology authorities with new test methods which can be brought rapidly to bear in cases of public health crisis. 

Its implementation is easy in small countries due to centralization of management and ease of surveillance of this new form of accreditation by a national accreditation body. Due to the long-standing establishment of validation of food microbiological methods in some countries, the beginning of validation of water microbiological methods, and establishment of European standards for the validation of food microbiological test methods (Microval project), the flexible-scope type of accreditation must be adapted to certain national requirements, but could prove less complex than the standard requirements. 

Water quality bioassay. 2. Environmental monitoring. 3. Water-Pollution. 4. Water-Microbiology. 5. Water chemistry. 6. Chemistry, Analytic. I. Greenwood, R. (Richard) II. Quevauviller, Ph. III. Title. 

Guidelines on quality assurance in food and water microbiology, E.A. Maier and N. Lightfoot Eds., Elsevier, Amsterdam, The Netherlands (1998). 

In the last decade, great effort has gone into the development of new, more rapid, detection methods. These methods are among others based on DNA and immunological techniques, but most of them are not yet routinely used in food and water microbiology laboratories. 

Within the EC, existing and proposed Directives have implications for food and water microbiology laboratories with respect to standardisation methods and laboratory accreditation if there is to be mutual recognition of results within the single market. It is therefore important to be able to check both the performance of a method (national or international) as well as that of individual workers. The reference materials which have been and which will be developed and hopefully certified, will thus be available for the verification of both types of performance. 

The microbial strains studied were Salmonella thyphimurium (two exercises). Listeria monocytogenes (two exercises) and later Bacillus cereus. Staphylococcus aureus, and Clostridium perfrengens for food microbiology, and Escherichia coli. Enterococcus faecium, Enterobacter cloacae and Staphylococcus warneri for water microbiology. The results were discussed in meetings with all participants. Several standard operating procedures common for several methods were developed, tested and amended, e.g. measurement of pH of culture media, measurement of temperature in incubators, statistical treatment of results, etc. 

Values of I z I over 2 should lead the concerned laboratory to investigate rapidly for the reasons of this weak performance before the next trial of the interlaboratory study starts. An example of z-score is shown in the section 12.5.6. Figures 12.3a-c show graphs of z-scores obtained in proficiency testing schemes carried out within the QUASIMEME (see section 12.5.6) and MICROBATH (bathing water microbiology method development study) frameworks. 

J.F. Hernandez, Sea water microbiology. Performance of methods for the microbiological examination of bathing water. Part 1. EUR Report 16601 EN, Luxembourg (1994). 

Chapelle, F.H., 2000. Ground-water Microbiology and Geochemistry. New York, John Wiley Sons, Inc., All pp. 

Lejeune, J. T., Besser, T. E., Merrill, N. L., Rice, D. H., and Hancock, D. D. (2001b). Livestock drinking water microbiology and the factors influencing the quality of drinking water offered to cattle. /. Dairy Sci. 84,1856-1862. 

Syrup or glass, [ajg +12.9 (c = 4.5 in water). Microbiological activity 20,000 LBF units/mg. An LBF unit is that amount of the growth factor contained in one mg of Basamine-Busch, a standard yeast extract manuf by Anheuser-Busch, Inc. 

More detailed information on source water microbiology and protection can be found in Pojasek [19] or in [16]. 

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