Don’t Permit Chemical Reuse Without Requalification in GMP Operations

Remember: Never reuse chemicals — including reagents, solvents, or buffers — unless requalified through validated testing procedures under GMP guidelines.

Why This Matters in GMP

Once a chemical is opened, used, or partially dispensed in a GMP process, its purity, sterility (if applicable), or stability may be compromised. Reusing such materials without validated requalification poses serious risks, including batch failure, inconsistent test results, and unknown degradation byproducts. Even seemingly stable substances can absorb moisture, oxidize, or undergo cross-contamination during handling.

For instance, reusing a buffer solution that has been left open during multiple assays without microbial or potency checks may introduce contaminants or change pH — leading to erroneous analytical outcomes or invalid results.

Regulatory and Compliance Implications

21 CFR Part 211.84 requires thorough testing of components, including chemicals, before use in manufacturing. EU GMP Chapter 5 mandates controls to ensure material suitability and traceability. WHO GMP emphasizes that materials must not be re-used unless validated and approved for such use.

Auditors closely evaluate chemical inventory logs, reuse policies, and material validation reports. Uncontrolled chemical reuse without requalification is typically cited as a critical lapse under GMP non-conformance