Microbiological Quality Control: Why Do We Bother?

Oral Presentation

Prepared by C. Fricker
CRF Consulting Ltd, 120 Allen Brook Lane, Williston, VT, 05495, United States


Contact Information: ColinFricker@aol.com; 802-878-5138


ABSTRACT

The increasing focus on the accuracy of results generated by laboratories has led to closer scrutiny of the quality control employed, although it appears that in water and food microbiology laboratories antiquated quality control procedures are acceptable in some areas in order to keep costs to a minimum. Most water laboratories employ quality control systems that are at best semi-quantitative but more often are completely qualitative. This is almost inconceivable given that the regulations for the presence of E. coli in drinking water discriminate between zero and one colony forming unit in 100 ml of water.

A comparison has been made between quantitative, semi-quantitative and qualitative QC procedures. Factors such as media preparation, media storage and temperature of incubation were varied and the ability of different QC protocols to identify problems was assessed. It became abundantly clear that the type of QC protocol employed by a majority of laboratories around the world were inadequate when trying to detect quality failures. The data from the comparison study will be presented together with suggestions as to how microbiological QC could be improved to begin to bring it in line with the QC procedures used in water chemistry laboratories.