Shelf life information sources

The peioxide and a2o thermal initiatois also aie photochemicady unstable and have been used as ladical sources at weU below thek nornial theimal decomposition tempeiatuies. Howevei, thek industiial use as photoinitiatois has been limited because thek light-absoiption chaiacteiistics fiequentiy aie unsuitable and because of the obvious potential complication owing to thek slow thermal decomposition, which leads to pool shelf-life and noniepioducible photoactivity in given formulations (88). Further information on photoinitiatois can be found in the Hteiatuie (92). 

Food additives (like color additives) can be added at various processing stages, but the additions are commonly made at the latest production stage before final marketing to ensure optimal functionality of the additive in the product as sold. Residues of additives used at earlier production stages may be present still in the final formulation. However, if they do not have further functions at that stage, they are considered process aids (to help preparation but without technological effects in the finished product) and are not indicated on labels. Some additives also decompose over time so that the levels present at the end of shelf life may be quite low. Several techniques and information sources can be used to assess contamination levels of chemicals ... 

Thus, it is no longer acceptable for the formulator to delay this compatibility testing until later in the development programme. The key message is for the formulator to test early and ensure equivalence of the whole product throughout the development cycle. Leachables are specifically mentioned data on their identity and concentration in the product and placebo are required through the shelf life and also under accelerated stability test conditions. Information should be submitted on source, chemical composition and physical dimensions of the container closure system, together with control and routine extraction tests. Acceptance criteria are also required. 

For products described in a pharmacopoeia, the official specifications can and should be used for the product file, with referral to the official source. The same applies to preparations from standard formulatimis, in which quality requirements are included. For in-house formulations, the quality requirements have to be set by an appropriately competent person internally. Useful information can be found in the formulatimi or validatimi studies. The results of stability studies may be useful when setting the quality requirements for the product, because the premise is that a preparation should comply to the quality requirements throughout the whole shelf life. An overview of the applicable quality requirements, including supporting information, has to be included in the product file. In addition it should be specified how the packaging and labelling are checked, and how and with what analytical method the product quality is controlled. Additionally the validation of the analytical methods is included in this section of the product file. 

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