ABSTRACT
The word bioburden has been ascribed subtly different meanings, not only in scientific texts, but also in official documents. Many authorities use the word simply in a quantitative sense, i.e., in a way suggesting merely a determination of numbers, with little or no specific mention of types of organisms present. ISO 111341, for example, defines bioburden as “Population of viable microorganisms on a raw material, component, a finished product and/or a package.” More commonly, however, the word implies both quantitative and qualitative characterization; thus, the glossaries of terms used in FDA2 and the European Community3 guidance on good manufacturing practice (GMP) explain bioburden in an identical manner:
“The level and type (e.g., objectionable or not) of microorganisms that can be present in raw materials, Active Pharmaceutical Ingredients (API) starting materials, intermediates or APIs. Bioburden should not be considered contamination unless the levels have been exceeded or defined objectionable organisms have been detected.” It is in this latter sense that the word will be used in this chapter.
