Sam Lazzara
Trusted Information Resource
In reviewing a contract manufacturer's EO sterilization process I see no evidence that a "bioburden resistance" study was performed to demonstrate that the resistance of the natural bioburden is equal to or less than the resistance of the biological indicator as per ISO 11135-1:2007 8.6.b and B.1.4.
This is typically achieved by performing short, sublethal cycles comparing natural product sterility to BI sterility, and there should be more growth among the BIs than the actual products. It can also be achieved by identifying the type and amount of natural bioburden on the product and doing a literature review to (hopefully) show that the natural bioburden organisms are less resistant than the indicator organism (B. atrophaeus).
The contractor's rationale is that the product bioburden is less than 1000 CFU. However, there is no evidence that the bioburden organisms have ever been identified so their resistance can be compared to B. atrophaeus. Nor have they done any sublethal studies as mentioned above.
I am pretty sure the rationale of having bioburden less than 1000 CFU is from a now superseded standard.
Any ideas about this?
This is typically achieved by performing short, sublethal cycles comparing natural product sterility to BI sterility, and there should be more growth among the BIs than the actual products. It can also be achieved by identifying the type and amount of natural bioburden on the product and doing a literature review to (hopefully) show that the natural bioburden organisms are less resistant than the indicator organism (B. atrophaeus).
The contractor's rationale is that the product bioburden is less than 1000 CFU. However, there is no evidence that the bioburden organisms have ever been identified so their resistance can be compared to B. atrophaeus. Nor have they done any sublethal studies as mentioned above.
I am pretty sure the rationale of having bioburden less than 1000 CFU is from a now superseded standard.
Any ideas about this?