| Liquid/Liquid Extraction of Aqueous Extracts prior to analysis | Compounds with a low partitioning into the organic phase might not be extracted via a Liquid/Liquid Extraction | Caprolactam, Pentaerythritol, etc. … | Verify the response of those compounds in other analytical screening methods (e.g., LC/MS APCI/ESI direct injection; derivatization GC/MS) |
| Chromatography | Compounds at levels high enough to cause detector saturation which may mask co-eluting compounds | Diethylhexyl phthalate from PVC, etc. … | Review chromatograms to surface potential compounds that could be masked and verify the response of those compounds in other analytical screening methods (e.g., LC/MS APCI/ESI direct injection; derivatization GC/MS) |
| Chromatography | Compounds eluting in the higher quantities causing a broad hump (e.g., Hydrocarbons for Rubbers) that could mask co-eluting compounds | Irgafos 168, BADGE related Compounds, etc. … | Screening the GC/MS chromatogram with an internal database could discover and identify these compounds (after deconvolutiona). Verify the response of those compounds in other analytical screening methods (e.g., LC/MS APCI/ESI direct injection; derivatization GC/MS) |
| Sample introduction | Thermolabile compounds may be partially or fully degraded in the inlet system | Silanes, n-nitrosamines, DINCH, Irgacure 907, n-alkylamines converted to N-methylene-n-alkylamines, pentaerythritol monostearate converted to pentaerythritol, etc. … | Having run authentic standards of each individual compound when building the IDB will show which compounds potentially will degrade, to what extent, and what could be formed as artifact.
Consider another orthogonal analytical method which addresses the compounds (e.g., LC/MS (ESI or APCI) or other) without degradation |
| Sample Preparation or Introduction | compounds react with extraction solvent (during extraction or in GC-inlet) leading to false extractables | Ester formation for acids when extracting with Ethanol or IPA | Consider use another organic solvent that does not react with the extractable (Hexane, dichloromethane). Capture such circumstances in an internal database. |
| Sample introduction | High boiling compounds remain in the inlet system and are not be transferred to the chromatographic column | High boiling Fatty Acids (>C24), Higher MW Polymer Additives. | The method's capabilities with respect to such compounds will be established during method optimization.
Verify the response of those compounds in other analytical screening methods (e.g., LC/MS APCI/ESI; derivatization GC/MS) |
| Chromatography | Some compounds with specific functional groups will show sub-optimal chromatography or will not elute. | Perfluorinated compounds, High MW Acids, Amines, thiols, sulfonic acids, epoxidized oils, etc. … | Experience with the analytical method will reveal compounds (with specific functional groups) that may show no/low responses or bad chromatography.
Verify the response of those compounds in other analytical screening methods (e.g., LC/MS APCI/ESI; derivatization GC/MS) |
| Mass Spectrometry | Compounds with higher MW may be missed because they fall outside the of the scanned mass range | Irganox 1076, Irgafos 168 Ox, tetrabromobisphenol A, etc. … | Experience with the analytical method will reveal compounds that may fall outside the MS detector range.
Make the MS-scan range broader.
Verify the response of those compounds in other analytical screening methods allow a proper safety assessment (e.g., LC/MS APCI/ESI; derivatization GC/MS) |