Heavy metals & traceability: building a supplier file that auditors like

Most delays in regulated projects come from documentation gaps, not from the material itself. This article is a lightweight checklist for controlling trace elements and building traceability evidence that stands up to supplier qualification reviews.

Auditors and supplier-qualification reviewers typically want two things: (1) evidence you understand and control critical risks, and (2) evidence you can trace lots and manage changes. You don’t need a 200-page binder—just the right artifacts, consistently.

What reviewers typically ask for

• Lot traceability from raw inputs to finished lots.
• Trace element limits and evidence of control (not necessarily a single ‘best’ value).
• Change control: how you will be notified if processes or sources change.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

Trace element control: a practical way to define limits

• Start with your risk assessment and device contact context.
• Define the ‘critical few’ elements and reasonable detection limits.
• Ask for ranges across lots (and how outliers are handled).

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

Traceability artifacts that help the most

• Lot/batch identifiers and mapping between steps.
• A clear COA scope statement (typical values vs full COA for production).
• Supplier statement on change notification and documentation availability.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

A supplier-file checklist

Rule of thumb: if a parameter affects your process, include the method and sample prep in the spec. That single line saves weeks later.

If you’re qualifying a new source

• Request two lots to understand variability before locking specs.
• Align on what’s public on the website vs what’s included in the full document package.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

Example spec snippet (copy/paste)

• Product: [phase/form factor]
• Particle size (PSD): [range] — Method: [laser diffraction / sieve / DLS], dispersion: [settings]
• Moisture: ≤ [x]% — Packaging: sealed, moisture-protected
• Documentation: Typical values for evaluation; Full COA for production lots on request
• Lot-to-lot variability: [acceptable ranges] for PSD/moisture/other critical items

Talk to us

Email info@kannrybio.com or use the contact form to discuss your target spec and stage (evaluation vs production). We can recommend a suitable grade and documentation scope.