Why is documentation issued per lot rather than per product?

Because analytical results describe measured material. A different lot is different material and has its own analytical history.

What should be done when the lot on a vial is not the lot on the document?

Treat the material as undocumented until the discrepancy is reconciled with the supplier. A non-matching document does not describe that vial.

What belongs in a custody record?

Receipt date and condition, storage location and conditions, every transfer of possession, and the date the container was first opened.

Does traceability establish safety?

No. Traceability establishes which material a record describes. It makes no statement about safety and no material described here is intended for human or veterinary use.

Laboratory Method Guide

Lot Numbers, COA Matching, and Chain of Custody

How lot identifiers link a physical vial to its analytical record, and what a documented custody trail is meant to establish.

The lot as the unit of documentation

Analytical documentation is issued per lot. A lot is the quantity of material produced or packaged under one set of conditions, and it is the only unit to which a test result properly applies.

That is why the lot identifier, not the compound name, is the key that connects a vial to its record. Two vials of the same compound from different lots have different analytical histories.

Matching a vial to its record

Read the lot identifier printed on the vial or its label.
Locate documentation issued for that exact identifier.
Confirm the compound name on the document matches the label.
Confirm the analysis date precedes the date the material is placed into use.
Treat any mismatch as unresolved until it is reconciled with the supplier.

What chain of custody records

A custody record documents who held material, when, and under what conditions, from receipt through storage to use or disposal. Its purpose is evidentiary: it allows a later result to be attributed to a specific physical sample.

In a laboratory setting a custody trail typically captures receipt date and condition, storage location and temperature, each transfer between custodians, and the date the container was first opened.

Receipt inspection

Record the date and time of receipt.
Note the condition of the outer packaging and any temperature indicator present.
Confirm that vial labels are legible and that lot identifiers match the packing documentation.
Record appearance of the cake or contents where visible.
Log the material into inventory under its lot identifier before storage.

Why traceability matters to interpretation

An analytical result without traceability cannot be tied to the material in hand. Traceability is what makes a purity or identity figure meaningful rather than merely indicative.

It also bounds a claim correctly: documentation supports statements about the tested lot and no other.

Frequently asked questions

Why is documentation issued per lot rather than per product?: Because analytical results describe measured material. A different lot is different material and has its own analytical history.
What should be done when the lot on a vial is not the lot on the document?: Treat the material as undocumented until the discrepancy is reconciled with the supplier. A non-matching document does not describe that vial.
What belongs in a custody record?: Receipt date and condition, storage location and conditions, every transfer of possession, and the date the container was first opened.
Does traceability establish safety?: No. Traceability establishes which material a record describes. It makes no statement about safety and no material described here is intended for human or veterinary use.

References

ISO/IEC 17025 — Testing and calibration laboratories — International Organization for Standardization
ICH Q7 Good Manufacturing Practice for Active Pharmaceutical Ingredients — International Council for Harmonisation

Research use only. The information in this library is educational and is not medical advice. Products are not intended to diagnose, treat, cure, or prevent disease and are not for human or veterinary consumption.