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| <h1 style="text-align:center">CHRIS: <font color="#0070C0">CH</font>emical <font color="#0070C0">RIS</font>k calculators - Total Quantity </h1> |
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| <h2 id="context-of-use-cou">Context of Use (COU)</h2> |
| <p>The total quantity module of the CHemical RISk calculator (CHRIS) |
| allows the user to …</p> |
| <p>The CHRIS - Total Quantity module outputs a predicted … For |
| additional details on the model please see this <a |
| href="https://www.sciencedirect.com/science/article/pii/S0273230023000739">article</a>.</p> |
| <p>The tool is limited by the assumptions upon which the model is based. |
| The salient limitations are enumerated below:</p> |
| <ol type="1"> |
| <li>The extractable is macroscopically homogeneous within the matrix. |
| Therefore, the output is only applicable to compounds that are |
| introduced either intentionally or unintentionally during synthesis |
| (e.g., residual monomers and oligomers, catalysts, initiators) or |
| compounding (e.g., stabilizers, antioxidants, plasticizers). The model |
| is not appropriate for surface residuals from processing, cleaning, and |
| sterilization.</li> |
| <li>The solvent is “perfectly mixed”. This should be a reasonable |
| assumption provided the samples are adequately agitated over the |
| timeframe of the testing. However, this assumption may not be |
| appropriate if sufficient agitation is not applied and a signficant |
| boundary layer develops that slows the release rate or if the extraction |
| is conducted under flow conditions.</li> |
| <li>Possible chemical reactions are not considered. Therefore, if the |
| polymer matrix undergoes substantive degradation during the extraction |
| test, the predictions may not be relevant. Further, the model does not |
| consider the potential for individual extractable compounds to degrade |
| over the selected timeframe.</li> |
| <li>The test article is comprised of a single polymer matrix. In |
| practice, complex devices may be comprised of multiple components and/or |
| polymer matrices. In these scenarios, careful consideration of the |
| potential contributions of each material constituent of the test article |
| to the extractables profile is critical when attempting to leverage the |
| model predictions.</li> |
| </ol> |
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