The Universe of Extractables (and potential leachables) is extremely diverse. The reason for this is that there are many different types of materials being used in the construct of a Container/Closure system or Medical devices, all with a different formulation, polymerization, processing and manufacturing. The impurities profile of a material is typically composed of compounds that were intentionally added to a material to protect the material during production or during its life cycle or to increase performance or functionality. In this case, we are talking about polymer additives, such as anti-oxidants, slip agents, acid scavengers, clarifying/nucleating agents, colorants, UV stabilizers, adhesives, etc…
However, there is even a longer list of compounds that are present in a material that were not intentionally added. These compounds have typically been introduced during the production process of the material or component, or they are the result of ageing of the material. Typical examples are solvent residues, cleaning residues, catalyst residues, oxidation/degradation compounds of the polymer, oxidation/degradation compounds of the polymer additives, polymer oligomers, etc…
The presentation will give an overview – for the most common materials used in the construct of container/closure systems or medical devices – of the main classes of compounds that are often detected in extractable studies and will explain why they are there, what their functions are (in case of the intentionally added substances) or what their sources are or how they have been formed (in case of unintentionally added substances).
Understanding the composition of a material and what the impact is on the extractables profile is an important and necessary first step in performing a proper evaluation of data and for a subsequent risk assessment. In addition, a good understanding of the material composition allows one to “fine tune” the analytical methods to guarantee that all compounds were properly picked up in the screening methods, guaranteeing the broad detection of extractable compounds and an associated correct identification.
