A metallized film never “complies” on its own. Compliance belongs to the finished article and to its intended use, so three questions decide every file: which layer touches the food, which substances can migrate out of the structure, and which test condition reproduces the way a customer actually uses the pack. Answer those three, document the answers, and food-contact compliance for metallized films turns into a checklist rather than a maze.

This guide walks through the EU route (Regulation (EU) No 10/2011 and its migration tests) and the US route (food-contact substance status plus chemistry data), and finishes with the documents your customers will ask for.

Everything below explains how the frameworks work. Treat it as orientation, not as a legal opinion, and confirm your own specification with an accredited laboratory and your regulatory consultant.

Question 1 — Which Layer Touches the Food?

Start with the structure drawing, because the answer changes the entire scope of testing. A typical metallized lidding or pouch laminate stacks four or five layers:

• an outer print web (usually PET)
• the metallized film, where an aluminium layer of roughly nanometre scale sits on a polymer carrier
• a laminating adhesive
• a sealant layer, most often cast polypropylene or polyethylene

In that stack the aluminium never touches the food. The sealant does. The general EU framework, Regulation (EC) No 1935/2004, plus the plastics regulation, therefore focuses the assessment on the food-contact layer, while still requiring the whole article to stay inert.

Flip the structure and the picture changes. Some wrappers, twist films and decorative food-contact surfaces expose the metallized side directly, which puts the aluminium layer and the coating process at the centre of the file. Our metallized PET film, metallized CPP film and metallized PE film product pages describe typical structures for each carrier.

One practical consequence: the sealant layer, the adhesive and the printing ink all need their own compliance statements. A perfectly compliant metallized web cannot rescue a non-compliant adhesive.

Question 2 — Which Substances Can Migrate?

On the EU side, Regulation (EU) No 10/2011 answers this with a Union list of authorised substances, individual specific migration limits (SMLs) and an overall migration limit (OML) of 10 mg per dm² of food-contact surface for plastics (testing overview). The official Union guidance on the Plastics Regulation explains how to apply those rules to real articles, including multi-layer constructions.

Where the aluminium layer enters the conversation

The 15th amendment to the Plastics Regulation, Regulation (EU) 2020/1245, replaced the element restrictions with a table of individual limits. Aluminium carries an SML of 1 mg/kg, alongside limits such as 0.02 mg/kg for nickel, 0.05 mg/kg for cobalt and “not detectable” requirements for lead, cadmium, mercury and chromium (Annex II element table).

That number matters because aluminium is not chemically inert in every food. A published study on aluminium migration from food-contact materials documents measurable transfer and links it to the simulant and the exposure conditions (aluminium migration study). Meanwhile EFSA, the EU risk assessor, keeps a tolerable weekly intake for aluminium at 1 mg per kg of body weight from all sources (EFSA aluminium assessment).

Four practical conclusions follow:

1. Keep the metal behind a barrier where the application allows it. A sealant layer that separates the aluminium from the food does most of the compliance work.
2. Test acidic foods specifically, because acid attacks the aluminium layer more aggressively than a neutral simulant does.
3. Remember that the coating process affects migration. Pinhole density and coating continuity decide how much metal a wet simulant actually meets — the themes behind our notes on optical density and on aluminium layer thickness and barrier performance.
4. Plan for non-intentionally added substances (NIAS) as well, because the regulation expects a risk assessment for reaction and breakdown products, not only for listed ingredients.

Question 3 — Which Test Condition Reproduces Your Use?

A test result means nothing without the condition attached to it. The EU framework links food types to simulants and to time-and-temperature conditions.

Two additions matter for metallized films. First, the overall migration test series, EN 1186, defines how to run these experiments on real articles rather than on flat film, including pouch-filling methods (testing overview). Second, sterilisation needs its own condition: standardised overall-migration test OM5 uses 2 hours at 100 °C or 1 hour at 121 °C for polyolefin food-contact layers (consolidated Annex V text) — the temperature regime our metallized CPP retort analysis exists to survive.

The US Route in Practice: Status First, Then Data

The American system asks two separate questions. First, does every substance in the structure have a status that permits food contact — a listing in Title 21 of the Code of Federal Regulations, a prior sanction, GRAS status, an effective Food Contact Notification, or a Threshold of Regulation exemption? Second, does the finished article meet its migration expectations under the intended use?

Two references do most of the work:

• 21 CFR 175.300 covers resinous and polymeric coatings, which many laminates and lacquers rely on.
• 21 CFR 176.170 defines food types and conditions of use, mapping them to extraction temperatures and times.

Then a caution that surprises many exporters: the FDA’s own chemistry guidance states plainly that the appropriate migration test conditions for a new food-contact substance are not simply the ones written into 21 CFR 175.300 or 176.170 (FDA chemistry recommendations). Build the protocol from the real intended use — a frozen pack, a retort pouch and a dry-snack wrapper each need a different design.

In practice, exporters solve this by collecting a compliance statement from every supplier in the stack, then testing the finished article once under the worst-case intended use.

Building the Compliance File: The Document Checklist

1. Structure drawing with layer order, thicknesses and the food-contact surface marked
2. Substance list per layer, with FCM or reference numbers for the EU and CFR citations for the US
3. Declaration of Compliance for every plastic layer, per Annex IV of the Plastics Regulation
4. Supplier declarations for inks, adhesives, primers and lacquers — including a statement on printing-ink set-off
5. Migration test plan for overall migration (EN 1186 series) and specific migration, including the element table that captures aluminium
6. Finished-article testing, covering seals, cut edges and closures rather than flat film alone
7. Post-sterilisation results where the pack faces retort or pasteurisation
8. GMP statement and traceability records, since Regulation (EC) No 2023/2006 requires documented good manufacturing practice
9. A re-test trigger list: film grade, adhesive, ink, aluminium thickness and process change all invalidate an old file

The fourth and seventh items give compliance teams more trouble than any others. Retort conditions and ink formulation change migration behaviour far more than most people expect, and our pharmaceutical metallized film packaging overview shows how the same logic plays out in a regulated medical context.

Seven Mistakes That Sink a Compliance File

1. Testing flat film instead of the finished article, seals included
2. Choosing the wrong simulant, especially for fatty and dry foods
3. Running an ambient condition on a product that a customer retorts
4. Ignoring the aluminium element limit because “the metal is only nanometres thick”
5. Missing a layer — an undisclosed primer or ink collapses the whole declaration
6. Copying a competitor’s compliance statement instead of building your own
7. Letting the file age after changing film supplier, adhesive or coating thickness

Frequently Asked Questions

1. Does a metallized film need food-contact approval? The finished article does, and every layer inside it needs a supporting status. The metallized web forms one part of that file, never the whole of it.

2. Does the aluminium layer need its own approval? It needs a documented status and a migration result. Under EU rules aluminium carries a specific migration limit of 1 mg/kg, so testing for the element belongs in every food-contact file that includes a metallized layer.

3. What limits apply under EU Regulation 10/2011? An overall migration limit of 10 mg per dm², specific migration limits for individual authorised substances, and the element limits introduced by Regulation (EU) 2020/1245 — aluminium at 1 mg/kg among them.

4. Which food simulant should I choose? Match the simulant to the food: water or 10% ethanol for aqueous products, 3% acetic acid for acidic ones, 50% ethanol for higher alcohol levels, vegetable oil or 95% ethanol for fatty foods, and Tenax for dry foods.

5. Can I test the film instead of the finished pack? You can screen a film for coating continuity, yet the compliance result belongs to the finished article. Test seals, cut edges and closures, because that is where real migration starts.

6. What is a Declaration of Compliance? A document issued under Annex IV of the Plastics Regulation that states the article’s compliance, the substances it contains, and the restrictions applying to its use. Each plastic layer in the structure needs one.

7. How does the FDA handle a metallized lidding film? The FDA route establishes a status for every substance — through 21 CFR, an effective Food Contact Notification or a Threshold of Regulation exemption — and then reviews migration data generated under the intended conditions of use.

8. What changes for retort or high-temperature applications? Everything about the test condition. Standardised retort conditions such as OM5 use 1 hour at 121 °C, and the migration levels you measure after sterilisation can differ from the ambient result.

The Takeaway

Food-contact compliance for metallized films follows one sequence: identify the food-contact layer, list every substance behind it, then reproduce the real use in the test protocol. Keep the aluminium layer behind a barrier where the structure allows it, test acidic foods with the element limits in view, and refresh the file whenever the film, adhesive, ink or coating recipe changes. Do that, and your metallized structure moves through customs and customer audits without surprises.

Building a food-contact structure or need the coating recipe documented for your compliance file? Send us your specification and our engineers will supply the process data your laboratory needs.