Finished Product Specifications

21 CFR 111.70(e) says: 'You must establish product specifications for the identity, purity, strength, and composition of the finished batch of the dietary supplement, and for limits on those types of contamination that may adulterate or lead to adulteration of the finished batch of the dietary supplement, to ensure the quality of the dietary supplement.' Each of the five attribute categories must be addressed — identity, purity, strength, composition, contamination limits — and the spec must apply to the finished batch (post-packaging, post-labelling, ready for distribution). The spec is not aspirational; the QC unit signs disposition against it, batch by batch, under §111.123.

• Identity — confirmation the supplement matches its label (correct dietary ingredients, in the correct dosage form). Often tested via a specific marker compound or finished-product chromatographic profile.
• Purity — freedom from undesired materials within the supplement matrix (e.g. absence of unspecified isomers, degradation products, residues from processing aids).
• Strength — assay of the labelled dietary ingredient(s) to the labelled level. The most-cited finding in the strength category is sub-potency — the assay returns less than the label claim — which is also the most-cited cause of FDA enforcement action.
• Composition — the supplement contains what the label says and nothing it does not. For multi-ingredient supplements this is often the most analytically demanding attribute, requiring multiple methods.
• Contamination limits — explicit acceptance limits on contaminants likely to be present given the ingredients, process and packaging. Standard panel: heavy metals (Pb, As, Cd, Hg) per California Prop 65 and USP <2232>; microbial (TAMC, TYMC, specified pathogens including Salmonella, E. coli, S. aureus) per USP <2021> / <2022>; mycotoxins for botanicals (aflatoxin, ochratoxin); pesticide residues for botanicals per USP <561>; residual solvents per USP <467> for extracted ingredients.

The strength spec must reconcile two realities: the labelled claim is what the consumer expects, and the analytical assay has variability + the product has shelf-life decay. The industry standard practice is an assay window — typically 90-150% of label claim at release for water-soluble vitamins, narrower for some pharmaceutical-grade ingredients, sometimes wider for botanicals where the marker-compound assay is inherently more variable. Overage at formulation (deliberately formulating above label claim to compensate for processing loss and shelf-life decay) is a manufacturing decision that must be justified and not used to mask a degraded ingredient or to make a sub-potent ingredient appear to meet spec. FDA's position is that the assay window must be scientifically justified by the validated method, the stability data and the manufacturing process — not picked to be permissive.

Contamination limits are the area where small supplement firms most often under-spec. The expectation is that the contamination panel and limits are matrix-appropriate: a fish-oil capsule needs heavy-metals and oxidation panel limits (TOTOX, peroxide value, anisidine value per AOCS); a botanical powder needs mycotoxin and pesticide panel limits; a probiotic needs viability + contamination panel; a powder blend in a non-RTE matrix may need a different microbial panel than a chewable. The USP general-chapter framework (<2232>, <2021>, <2022>, <467>, <561>, <2750>) is the de facto reference. California Prop 65 thresholds are an additional commercial overlay — products sold in California must not trigger the Prop 65 warning, which is independent of the FDA cGMP framework but operates in parallel.

111.75(c) allows two paths to confirm the finished-product spec is met: test every batch, or use a scientifically valid statistical sampling plan combined with documented controls that justify the reduced testing frequency. The sampling-plan option is attractive economically but operationally heavy — it requires a documented basis (typically AQL-based attribute sampling such as ANSI/ASQ Z1.4 plus a documented justification of the AQL chosen, the lot-size relationship, and the discriminating power of the plan). Most small and mid-size supplement firms find testing every batch operationally simpler and audit-defensible; large-volume manufacturers with high-discrimination process controls and PAT-style in-process monitoring are the realistic candidates for the sampling-plan path.

1. Spec missing one or more of the five attribute categories — frequently 'purity' or 'contamination limits' omitted on multi-ingredient products.
2. Strength acceptance range too wide and not scientifically justified.
3. Contamination limits not matrix-appropriate (e.g. no mycotoxin limit on a botanical powder, no oxidation panel on a fish-oil product).
4. Spec written once, never re-evaluated when formulation, supplier or process changed (the spec drifted out of alignment with what the product actually is).
5. Methods cited in the spec not validated for the actual product matrix — overlaps with §111.320.
6. Sampling-plan option selected without the underlying statistical basis documented, or with a sample size that has no realistic discriminating power.
7. QC unit released batches against an outdated spec version (overlaps with §111.103 written-procedure control).
8. Label claim inflated relative to validated assay capability — the spec window cannot reliably distinguish meeting label claim from falling short.

Searches like 'finished product specification template dietary supplement', '111.70(e) compliance', 'supplement product spec sheet', 'how to write a dietary supplement specification' come from formulators and quality leads who are either preparing a contract-manufacturer customer audit, responding to a 483, or building out a private-label brand that has just learned the contract manufacturer holds the spec but the brand owner is the legal manufacturer. The buying motion is for a system that holds the spec under version control, links it to the formulation, drives the testing requirement, captures the QC unit release decision against it, and renders the inspector-ready evidence pack per batch.

• Spec master per finished product — five required attribute sections, each requiring at least one acceptance criterion with a method reference, before the spec can be activated.
• Version control — each spec is a versioned document; activating a new version requires QC unit two-person e-sig and inherits a documented change history.
• Method linkage — each spec acceptance criterion points to a validated method (§111.320) that must be in 'qualified' status; an expired method blocks new batch release.
• BOM linkage — the spec is tied to the formula version; an unauthorised formulation change cannot be released against an old spec.
• Per-batch release contract — QC unit release requires evidence that every spec attribute has been tested or covered by a §111.75(c) sampling plan; release is blocked otherwise.
• Sampling-plan support — Z1.4 plans can be configured on the spec, with the AQL and lot-size relationship stored as part of the spec versioned document.
• Stability bridge — the spec attributes the stability program watches across shelf-life are tagged; a stability excursion automatically re-evaluates the assay window justification.
• Inspector-ready evidence pack — one-click render of the active spec, its version history, the methods supporting it, and the release records for a date range.