Bioburden determination

The term bioburden is used to describe the concentration of microorganisms in a material this may be either a total number of organisms per millilitre or per gram, regardless of type, or a breakdown into such categories as aerobic bacteria or yeasts and moulds. Bioburden determinations are normally undertaken by the supplier of the raw material, whose responsibility it is to ensure that the material supplied conforms to the agreed specification, but they may also be checked by the recipient. The... 

In this section only the bioburden determination of a parenteral product solution for aerobic isolates is discussed and details regarding bioburden testing of facility or equipment surfaces are not included. For parenteral products, bioburden is usually estimated on the unfiltered bulk product solution (UBPS). In this way the test will indicate the total microbial load culminating in the batch solution as a result of the various contributing factors such as all batch ingredients, manual manipulations, and environmental fallout. Testing of filtered bulk parenteral solution either before or after filling into the final container may be done for comparison to the previously tested unfiltered bulk solution or to comply with the directives from European inspectors. All isolates should be identified to the species level whenever possible. The... 

With medical devices, the first stage in bioburden determination is to remove microorganisms from the device and suspend them in a fluid diluent for subsequent manipulation. 

The first issue in bioburden determination that merits validation is the choice of fluid used in preparatory stages of removal of microorganisms from devices and for suspending, dissolving, and diluting dosage forms. Phosphate buffer pH 7.2. buffered sodium chloride-peptone solution pH 7.0, and lactose broth are recommended in the various compendia. Saline, Rtnger s solution, and... 

It is necessary to determine the bioburden and make cycle verification studies when ethylene oxide sterilization is used, as it is for other sterilization methods. The manufacturer of hospital sterilization equipment provides cycle recommendations based on the expected bioburden and the consideration of an appropriate safety factor. In ethylene oxide sterilization, it is necessary to determine if residues of the stefilant are absorbed by the sterilized article, and to examine the possible formation of other potentially toxic materials as a result of reaction with ethylene oxide. 

A typical ETO sterilization cycle is shown in Fig. 10. As discussed at the beginning of this section, it is important to determine and monitor the bioburden level of the product entering the sterilizer. Also, the load configuration in the sterilizer is important in achieving uniform and reliable sterilization. Unfortunately, commercially available biological indicators used in ETO sterilization are often unreliable. Hopefully, progress will be made in this field in the years ahead. 

The biological indicator can be prepared to adequately challenge a sterilization cycle designed to provide a 10 6 probability of microbial survival with respect to indigenous bioburden. The concentration of spores utilized as the biological indicator can be determined from the following formula ... 

It Is appropriate to increase or decrease sampling based on the trend performance. The time and date will be determined according to the activity. The (specify year) microbiological water testing report, "Water Systems Bioburden and Bacterial Endotoxin Summary Report for Year (specify)," is also included in (provide reference attachment number). 

Bioburden testing is performed on components prior to steam sterilization as verification that the sterilization parameters are sufficient for sterilization of components. The method for determining the bioburden level of components is included in the manufacturing site standard test method. For product component bioburden summary, refer to (provide reference attachment number). 

SUBJECT Determination of Components Bioburden before Sterilization... 

Section Val. 1900 includes four aseptic processes associated with monitoring and qualification programs covering determination of components bioburden before sterilization sterility test failure investigation, bacterial endotoxin determination in WFI, in-process finished product, and monitoring the bioburden, spore bioburden, and endotoxin present on stoppers and unprocessed vials. 

The overkill approach is selected for the validation study. This eliminates the need for bioburden and resistance studies. The objective is to ensure that the coolest area in the loading pattern, as determined in earlier heat-penetration and heat-distribution studies, receives sufficient heat to cause a 12-log reduction in the biological indicator chosen. 

Bioburden loading levels were determined by a membrane filtration procedure prior to washing and also after the spiking to confirm that the desired challenge level was achieved. Following the cleaning cycle, the same procedure was used to evaluate residual bioburden. To recover the residual contaminants, sterile peptone water USP is used to rinse the entire inner surface of each vial. Results are reported as CFU per vial. 

The objective of the microbial monitoring program is to obtain representative estimates of the bioburden of the environment. When data are compiled and analyzed, any trends should be evaluated by trained personnel. While it is important to review environmental results on the basis of recommended and specified frequency, it is also critical to review results over extended periods to determine whether or not trends are present. Trends can be visualized through the construction of statistical control charts that include alert and action levels. The microbial control of controlled environments can be assessed in part on the basis of these trend data. Periodic reports or summaries should be issued to alert the responsible manager [13]. 

Approaches) to setting limits—The approach to setting limits will be determined by the nature of the residue(s) and may differ for different situations within the same company. For example, the approach will differ for the calculation of residues associated with the manufacture of APIs and their related intermediates and precursors. Of necessity, it will also differ for the approach to be used for limits for residues associated with the production of such dosage forms (e.g., actives, detergents, and bioburden). It is not necessary to elaborate on the approach to setting limits in the CVMP. In fact, it is usually a mistake to do so. It is sufficient to indicate in the CVMP that limits will be established and justified for all potential contaminants and that this information will be included in the scientific rationale section of the individual protocols. 

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