Standard Operating Procedure for Monitoring of Recovered Solvent Odor and Clarity in API Manufacturing

Department	API Manufacturing
SOP No.	SOP/API/057/2025
Supersedes	SOP/API/057/2022
Page No.	Page 1 of 10
Issue Date	13/04/2025
Effective Date	15/04/2025
Review Date	13/04/2026

1. Purpose

To define the procedure for monitoring the organoleptic properties—odor and clarity—of recovered solvents in API manufacturing, ensuring that only solvent batches meeting specified criteria are reused in production.

2. Scope

This SOP applies to all recovered solvents generated through distillation or purification processes in the API plant, prior to their reuse, reprocessing, or disposal.

3. Responsibilities

• Production Operators: Collect samples of recovered solvents for visual and odor evaluation.
• QC Department: Perform clarity inspection and odor assessment against standard references.
• QA Department: Review results and approve for reuse or recommend re-distillation/disposal.

4. Accountability

The QC Manager is accountable for executing and documenting organoleptic evaluations. The QA Manager is responsible for ensuring that recovered solvents meet quality and GMP standards before release.

5. Procedure

5.1 Sampling of Recovered Solvents

1. After recovery, transfer solvent into clean, labeled sampling containers.
2. Collect samples in amber glass bottles with tight-fitting caps to avoid odor dissipation.
3. Label with:
   • Solvent Name
   • Batch Number
   • Date of Recovery
   • Operator Initials

5.2 Odor Evaluation

1. Carry out odor check in a ventilated area free from interfering odors.
2. Open sample container gently and sniff from the mouth of the bottle (do not inhale directly).
3. Compare odor with a fresh reference standard of the same solvent.
4. Record observations as:
   • No Odor
   • Characteristic Odor
   • Unpleasant/Off Odor

5.3 Clarity Evaluation

1. Pour solvent sample into a colorless glass tube (15–25 mm diameter).
2. Hold the tube against a white and black background under adequate lighting.
3. Check for:
   • Particulates
   • Turbidity
   • Color deviations
4. Record clarity as:
   • Clear
   • Hazy
   • Colored

5.4 Acceptance Criteria

1. Odor: Must be characteristic and comparable to fresh solvent.
2. Clarity: Must be clear and free from suspended matter.
3. If solvent fails either test:
   • Send for re-distillation or discard as per SOP/API/049/2025
   • Document the rejection in “Recovered Solvent Evaluation Log” (Annexure-1)

5.5 Documentation

1. Record:
   • Solvent name
   • Batch No.
   • Odor & clarity results
   • Approved/Rejected
   • Checked by

   in Annexure-1.

2. QA to sign off on approved lots in the solvent status label and batch release form.

6. Abbreviations

• SOP: Standard Operating Procedure
• QC: Quality Control
• QA: Quality Assurance
• GMP: Good Manufacturing Practice

7. Documents

1. Recovered Solvent Evaluation Log (Annexure-1)
2. Reference Solvent Odor and Clarity List

8. References

• ICH Q7 – GMP Guidelines for Active Pharmaceutical Ingredients
• 21 CFR Part 211 – Finished Pharmaceuticals
• Internal QC Work Instruction Manual

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Recovered Solvent Evaluation Log

Date	Solvent	Batch No.	Odor	Clarity	Status	Checked By
13/04/2025	Acetone	RCV-2025-004	Characteristic	Clear	Approved

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
01/01/2022	1.0	Initial Release	New Recovery Evaluation Protocol	QA Head
13/04/2025	2.0	Clarified Acceptance Criteria and Annexure Format	QA Review Update	QA Head