Selection of a new disinfectant for Secondary Pharmaceutical Facilities

A new disinfectant should not be recommended to manufacturing centers without performing efficacy work and ensuring that its effectiveness is equivalent to or better than current agents. A rationale report is required to document the reasons for introducing a new disinfectant. The following guidelines should be used as a basis for identifying a suitable disinfectant.

1. The disinfectant should have no associated Health and Safety implications
   which may present a serious risk to the end user.
2. The disinfectant must have been validated and should demonstrate suitable
   activity under the conditions of its proposed uses.
3. The disinfectant should not leave harmful or otherwise unwanted residues following its use.
4. The disinfectant must be filterable through a 0.2µ membrane. It must not
   react with the membrane material.
5. The disinfectant must not form precipitates or inactivate other agents which it is likely to come into contact with. This will be critical if the disinfectant is to be used as part of rotational pair.

Sporicidal Activity of Disinfectants
General purpose disinfectants such as alcohols , quaternary ammonium compounds and amphoterics do not have specific sporicidal activity. Only chlorine, hydrogen peroxide or aldehyde based agents are regarded as being sporicidal. Sporicidal agents are validated as outlined using a spore suspension of a suitable organism e.g. Bacillus subtilis.

Validation Status Checking of Previously Approved Disinfectants
A reduced number of stock cultures may be used for validation status checking of previously approved disinfectants, allowing that at least one Gram-negative, one Gram-positive, one mould and one spore forming bacterium (for sporicidal agents only) is included. Local isolates must be included. The activity should be evaluated on aged concentrate where possible.

Allocation of expiry dates and determination of the shelf-life of Disinfectants
The following procedures can be used to evaluate disinfectant efficacy after being held for its maximum in-use shelf-life. Allocation of expiry dates should be done at the time of approval of a new disinfectant. All of the stock cultures included in the following list should be checked, and local isolates must be included. The effectiveness of the disinfectant should be checked against the organisms in, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9027, Escherichia coli ATCC 8739, and Enterococcus hirae ATCC 10541. Additional Microorganisms may be chosen as required. This may include isolates against which suitable activity must be demonstrated eg. Micrococcus luteus ATCC 9351, Salmonella abony NCTC 6017 Agents which are to be evaluated for sporicidal activity should be tested with: Bacillus subtilis ATCC 6633 Agents which are to be evaluated for fungicidal activity should be tested with: Aspergillus niger ATCC 16404, Candida albicans ATCC 10231.

The disinfectants should be evaluated under the conditions of use. If the disinfectant is to be used at ambient temperature. The test should be carried out under conditions which reflect this practice. The method must be validated for each disinfectant. It is necessary to validate the method against each microorganism which is used in the test. The validation of a disinfectant should include the following test regimes as a minimum requirement.
Validation of the efficacy of the disinfectant against a range of isolates and the establishment of surface contact times, Validation of the surface activity of the disinfectants under the conditions of use, Validation of the shelf life of the disinfectants.