Walk on the wild side: The application of environmental isolates in microbiological testing

Environmental isolates are commonly used in the pharmaceutical sector to challenge microbial test methods and to release culture media. Does the use of these organisms add value? There are arguments in favour of this practice (broadening the test panel and with the assumption that some ‘wildtype’ characteristics are retained) and against (such as environmental isolates being difficult to standardise and the expectation that ‘wildtype’ characteristics are lost at some time point or they are not retained at all with the first subculture onto laboratory media). This paper considers these arguments.