FDA 21 CFR and Your Pigment Spec — Indirect Food Contact, No Jargon, No Guessing

FDA 21 CFR and Your Pigment Spec — Indirect Food Contact, No Jargon, No Guessing

TL;DR — The US FDA does not approve or certify pigments. It publishes conditions of use under 21 CFR. If your pigment sits behind a functional barrier in a coating on paper, metal, or plastic that contacts food, you need to show compliance with §175.300, §176.170, or §177.2600. This means migration data — not a certificate. Below is what that actually looks like for a formulator sourcing organic pigments.

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“FDA Approved Pigment” Doesn’t Exist

Walk any trade show and you’ll hear it. “This grade is FDA approved.” It isn’t.

The US FDA does not maintain a list of approved pigments. It does not issue pigment certifications. What it does — under Title 21 of the Code of Federal Regulations — is define conditions under which substances may safely contact food, directly or indirectly.

A pigment in a printing ink or coating that contacts the outside of a food package is an indirect food additive. The FDA regulates it not by approving the pigment, but by setting the rules for the finished article: the coating, the printed film, the can lining.

Your pigment spec doesn’t need a stamp. It needs data that answers one question: does anything migrate?

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Three CFR Sections That Matter (and When Each Applies)

If you formulate packaging inks, can coatings, or printed films, three sections of 21 CFR cover almost every scenario you’ll hit.

§175.300 — Resinous and Polymeric Coatings

This is the workhorse. It covers coatings applied to metal, glass, plastic, or paper that become part of the food-contact surface — think can linings, crown cork seals, and film laminations.

The key concept: §175.300 lists permitted coating components. Pigments fall under “colorants” in paragraph (b)(8). They must be “generally recognized as safe” or shown not to migrate to food under the intended conditions of use.

What matters in practice:
– The coating must form a continuous film that cures properly.
– Migration testing uses food simulants, not the actual food product.
– If the coating passes extraction testing under §175.300(d), the pigment — as part of the cured film — is compliant.

§176.170 — Paper and Paperboard in Contact with Aqueous and Fatty Foods

This is the section for paper packaging. Pizza boxes, bakery tissue, paper cups, folding cartons for dry and fatty foods.

Pigments in printing inks applied to the non-food-contact side of paper or paperboard fall here. Even if the ink never touches the food directly, §176.170 controls what can be in the paper structure, including components that could migrate through the substrate.

The dividing line between §176.170 and §175.300 often comes down to whether there’s a functional coating. If the paper has a polymeric coating, §175.300 may override.

§177.2600 — Rubber Articles Intended for Repeated Use

Less common for pigment buyers, but worth knowing. This covers rubber gaskets, seals, tubing, and conveyor belts used in food processing.

If your pigment goes into an EPDM gasket compound for a dairy filler, §177.2600 sets extractive limits. The rubber article is extracted in water and n-hexane, and total extractives must be below specified limits. The pigment is part of that extraction mass.

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What “Indirect Food Additive” Actually Means for Your Formulation

Here’s what separates a spec that clears FDA review from one that triggers questions.

The Functional Barrier

The FDA’s position: if a functional barrier separates the pigment from food, and migration data shows nothing crosses that barrier at detectable levels, the pigment is not a food additive in the legal sense.

A functional barrier can be:
– The cured binder film of a can coating (epoxy, polyester, acrylic)
– The substrate thickness of paperboard (>300 µm is typical)
– A polyolefin layer in a laminated film structure

No barrier is absolute. The burden is on you — or your supplier — to show that under worst-case conditions (temperature, time, food type), nothing migrates.

Migration Testing — What Actually Gets Run

The test protocols follow FDA Guidance for Industry: Preparation of Premarket Submissions for Food Contact Substances (Chemistry Recommendations). The standard simulants:

Simulant	What It Models	Typical Condition
10% ethanol (v/v)	Aqueous foods (pH > 5)	40°C / 10 days
50% ethanol (v/v)	Dairy, low-alcohol beverages	40°C / 10 days
Corn oil (or 95% ethanol as fatty simulant)	Fatty foods	40°C / 10 days

Temperature and time scale with intended use:
– Room-temperature shelf storage: 40°C / 10 days
– Hot fill: 66°C / 2 hours followed by 40°C / 10 days
– Retort: 121°C / 2 hours followed by 40°C / 10 days

Migration Limits

There is no single FDA number for “acceptable pigment migration.” The limit is set case by case, based on toxicological data for each migrating substance.

In practice, for most organic pigments used in indirect contact:
– Detection limits of 10 ppb (parts per billion) are the working threshold.
– Individual substances with toxicological concern may be subject to lower limits (e.g., < 0.5 ppb for certain primary aromatic amines).
– If nothing is detected above 50 ppb total non-volatile extractives, most FDA reviewers consider the exposure de minimis for indirect contact through a functional barrier.

This is why raw material purity matters. A pigment at 98% purity with 2% impurities (unreacted intermediates, processing aids) gives you more things to explain in a migration study than a grade at 99.5%.

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Pigment Chemistries That Work (and One That Needs a Second Look)

Some pigment classes are structurally suited to indirect food contact. Others need case-by-case evaluation. Here’s the breakdown.

Phthalocyanine Blues and Greens — PB15:0, PB15:1, PB15:3, PB15:4, PG7

This is the first place formulators look, and for good reason. Phthalocyanines have molecular weights around 575–1,100 g/mol, essentially zero water solubility, and exceptional thermal stability.

At 40°C in any simulant, migration of the intact pigment molecule is below detection limits. The pigment doesn’t dissolve. It doesn’t decompose below 400°C. There’s simply no mechanism for it to cross a cured coating film.

Honor’s PB15:3 grade (HP Blue 4559) and PG7 grades ship with full batch documentation for regulated applications.

If you can hit your color target with phthalocyanine chemistry, you’re in the lowest-risk category for FDA indirect-contact review.

DPP Reds — PR254, PR255, PR264

Diketopyrrolopyrrole (DPP) pigments have molecular weights of 288–400+ g/mol with strong intermolecular hydrogen bonding in the crystal lattice. That lattice doesn’t break apart at food-contact temperatures.

PR254 (the workhorse DPP red) has measured solubility in ethanol below 0.1 mg/L at 25°C. At 40°C in 95% ethanol (worst-case fatty simulant), migration remains below 10 ppb in cured coating systems.

These are the pigments formulators reach for when they need a clean mid-red without the amine-release questions that come with azo reds. Read our DPP vs Quinacridone comparison for a deeper dive on chemical stability.

Quinacridones — PR122, PR202, PV19

Quinacridones have molecular weights in the 312–340 g/mol range, but the crystal structure is the real story. The lattice is held together by NH···O hydrogen bonds between adjacent molecules. That network doesn’t yield to food simulants at 40°C.

PR122 (2,9-dimethylquinacridone) is arguably the benchmark for magenta in indirect food-contact applications. PV19 (quinacridone violet) has some solubility in strongly alkaline conditions, which is irrelevant for food packaging pH ranges (2.5–7.0).

Both PR122 and PV19 show no detectable migration (< 5 ppb) in 10% ethanol and 50% ethanol at 40°C / 10 days.

⚠️ Azo Pigments — PY12, PY13, PY14, PY83, PR57:1

This is where you need to slow down.

Diarylide yellows (PY12, PY13, PY14, PY83) and lithol rubine (PR57:1) are azo pigments. Under certain conditions — heat, acidic or alkaline environments, prolonged contact — azo pigments can undergo reductive cleavage, releasing primary aromatic amines (PAAs).

PAAs are the concern. Compounds like 3,3′-dichlorobenzidine (DCB, from diarylide pigments) and 2-amino-5-methylbenzenesulfonic acid (from PR57:1) have toxicological profiles that attract regulatory scrutiny.

This does not mean azo pigments are banned for indirect food contact. It means:
– You need migration data showing no detectable PAA release under the intended conditions of use.
– Detection limits for specific PAAs are typically pushed down to 0.5–5 ppb.
– If the pigment is behind a proven functional barrier with < 10 ppb total migration, the PAA question is usually moot — but the data file needs to be there.

If you’re buying diarylide yellows like PY12 for a packaging application, ask the supplier for PAA release data under 40°C / 10-day simulant conditions. If the supplier can’t provide it, you’re building your own data file — or you’re switching to a DPP or quinacridone alternative.

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Supplier Audit Checklist — What to Ask, What to Keep

When you’re qualifying a pigment supplier for indirect food-contact work, these are the documents and data points that separate a serious partner from a trader with a brochure.

1. Batch-level Certificate of Analysis (COA)
2. Purity by HPLC or UV-Vis (not just color strength)
3. Heavy metals: Pb, Cd, Hg, Cr(VI) — target < 10 ppm each

4. Polychlorinated biphenyls (PCBs): < 25 ppm for phthalocyanines (per FDA expectations for non-dioxin-like PCBs)

5. Heavy Metal Compliance Statement

6. CONEG (Coalition of Northeastern Governors) model legislation limits: Pb + Cd + Hg + Cr(VI) < 100 ppm total

7. EU Directive 94/62/EC packaging limits: same 100 ppm total

8. Migration Study (if available)

9. Worst-case simulant: 95% ethanol or corn oil at 40°C / 10 days
10. Total non-volatile extractives < 50 ppb

11. Specific PAA scan for azo pigments (LC-MS/MS, LOQ ≤ 5 ppb)

12. GMP Statement

13. Manufactured under Good Manufacturing Practices per 21 CFR §110

14. No cross-contamination with non-food-grade materials on shared equipment

15. Supply Chain Traceability

16. Can the supplier trace every intermediate and starting material back to the manufacturer?

17. Is the pigment produced in a dedicated or segregated facility?

18. Documentation Readiness

19. REACH compliance statement (required for EU, useful as supporting data for FDA)
20. FDA-related documentation on request: purity specs, heavy metal data, migration summaries

The short version: if a supplier can’t produce batch-level purity and metals data within 24 hours of your request, keep looking.

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FAQ

Does the FDA approve pigments for food packaging?

No. The FDA does not approve or certify individual pigment products. It publishes conditions of use under 21 CFR (§175.300, §176.170, §177.2600) that define when a substance — including a pigment — can be used in indirect food-contact applications. Compliance is demonstrated through migration data, not a certificate of approval.

What’s the difference between “FDA compliant” and “FDA approved”?

“FDA approved” is a legal claim that means the FDA has reviewed and authorized a specific product. That doesn’t happen with pigments. “FDA compliant” means the pigment, used as directed in a finished article, meets the conditions described in the relevant 21 CFR section. The former is a claim nobody can make. The latter is what your migration data supports.

Can I use PY12 (diarylide yellow) in food packaging ink?

Yes, but with documentation. PY12 is not banned. What matters is whether the finished printed article — the coated paper or film — releases primary aromatic amines (PAAs) from azo cleavage above detectable levels. If you can show < 5 ppb total specific PAAs under your intended conditions of use (temperature, food type, shelf life), and the pigment is behind a functional barrier, PY12 can be viable. Get the PAA migration data from your supplier before you commit to the spec.

What migration data should I ask my pigment supplier for?

At minimum, total non-volatile extractives in 95% ethanol at 40°C / 10 days, with a target of < 50 ppb. For azo pigments, add an LC-MS/MS scan for specific primary aromatic amines (DCB, aniline, toluidines) with limits of quantitation ≤ 5 ppb. For phthalocyanines, heavy metal and PCB data often matter more than migration data — the intact pigment won’t migrate. Browse our product catalog to see the documentation we ship with every batch.

Where can I find the actual 21 CFR text?

The full 21 CFR is maintained at ecfr.gov. Direct links:

• §175.300 — Resinous and polymeric coatings
• §176.170 — Components of paper and paperboard in contact with aqueous and fatty foods
• §177.2600 — Rubber articles intended for repeated use

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The Bottom Line

Indirect food-contact compliance for organic pigments is not a certificate on the wall. It’s a data file you can defend.

Pick the right chemistry — phthalocyanine, DPP, quinacridone — and you’re dealing with molecules that don’t migrate by design. Use azo pigments where cost demands it, but own the PAA data.

When you source, ask for batch COA, metals data, and migration summaries. If the supplier hesitates, move on.

View our full pigment range or contact us for grade-specific FDA documentation.