The International Council  on Harmonisation (ICH) has developed maintenance procedures  (PDF - 26KB) for revising the permitted daily exposure (PDE) of solvents included in the Q3C guidance

This web page makes available to the public all recommendations, decisions, and other information related to the revision of the Q3C tables and list (PDF - 183KB).

• Draft Recommendations for New PDEs
   
  • 2-Methyltetrahydrofuran
    • ICH Step 2 recommendation:  Impurities:  Residual Solvents (Maintenance) PDE for 2-Methyletrahydrofuran (PDF-134KB), Q3C(R8) Recommendations for the Permitted Daily Exposures for Three Solvents—2-Methyltetrahydrofuran, Cyclopentyl Methyl Ether, and Tert-Butyl Alcohol,—According to the Maintenance Procedures for the Guidance Q3C Impurities: Residual Solvents; International Conference on Harmonization; Availability
  • Cyclopentyl Methyl Ether
    • ICH Step 2 recommendation:  Impurities:  Residual Solvents (Maintenance) PDE for Cyclopentyl Methyl Ether (PDF- 134KB), Q3C(R8)  Recommendations for the Permitted Daily Exposures for Three Solvents—2-Methyltetrahydrofuran, Cyclopentyl Methyl Ether, and Tert-Butyl Alcohol,—According to the Maintenance Procedures for the Guidance Q3C Impurities: Residual Solvents; International Conference on Harmonization; Draft Guidance for Industry; Availability
  • Tert-Butyl Alcohol
    • ICH Step 2 recommendation:  Impurities:  Residual Solvents (Maintenance) PDE for Tert-Butyl Alcohol (PDF- 134KB), Q3C(R8) Recommendations for the Permitted Daily Exposures for Three Solvents—2-Methyltetrahydrofuran, Cyclopentyl Methyl Ether, and Tert-Butyl Alcohol,—According to the Maintenance Procedures for the Guidance Q3C Impurities: Residual Solvents; International Conference on Harmonization; Availability

• Final Recommendations for Revision to the List

  • Triethylamine and Methylisobutylketone
    • ICH Step 2 recommendation for revision:  Impurities:  Residual Solvents (Maintenance) PDE for Triethylamine (PDF - 87KB) Draft Recommendations for the Revision of the Permitted Daily Exposures (PDE) for Two Solvents, Triethylamine and Methylisobutylketone, According to the Maintenance Procedures for the Guidance Q3C Impurities: Residual Solvents; International Conference on Harmonization;  
       
  • Tetrahydrofuran (THF)
    • ICH Step 4 recommendation for revision: Impurities: Residual Solvents (Maintenance) PDE for Tetrahydrofuran (PDF - 67KB)  International Conference on Harmonisation; Final Recommendations for the Revision of the Permitted Daily Exposures (PDE) for Two Solvents, N-Methylpyrrolidone and Tetrahydrofuran, According to the Maintenance Procedures for the Guidance Q3C Impurities: Residual Solvents; Availability. (FR 68(219):64352 - 11/13/2003)
  • N-Methylpyrrolidone (NMP)
    • ICH Step 4 recommendation for revision: Impurities: Residual Solvents (Maintenance) PDE for N-Methylpyrrolidone (NMP) (PDF - 69KB)  International Conference on Harmonisation; Final Recommendations for the Revision of the Permitted Daily Exposures (PDE) for Two Solvents, N-Methylpyrrolidone and Tetrahydrofuran, According to the Maintenance Procedures for the Guidance Q3C Impurities: Residual Solvents; Availability. (FR 68(219):64352 - 11/13/2003)
  • Cumene
    • ICH Step 4 recommendation for revision: Impurities: Residual Solvents (Maintenance) PDE for Cumene (PDF - 119KB) International Conference on Harmonization: Final Recommendations for the Revision of the Permitted Daily Exposures (PDE) for Cumene, According to the Maintenance Procedures for Q3C Impurities:  Residual Solvents; Availability. (FR 77(36): 10754 - 2/23/2012)