Food contact material testing according to FDA requirements

To sell food packaging and other food contact articles in the US, manufacturers must comply with U.S. Food and Drug Administration (FDA) regulations. This includes ensuring that each individual food contact substance (FCS) used to produce such articles meets one of the following conditions:¹

• It is listed in Title 21 of the U.S. Code of Federal Regulations (21 CFR) as an indirect food additive or Prior Sanctioned substance approved for the intended use case.

• It is Generally Recognized as Safe (GRAS) when used in food contact applications.

• It is covered by a Threshold of Regulation (TOR) exemption.

• It has been approved under a Food Contact Substance Notification (FCN) and has been acquired from the supplier specified in that notification.

The manufacturer must also ensure that substances are not transferred to food in amounts that would negatively affect consumer health. This is achieved through migration or extraction testing, where the concentration of extractives is measured and contrasted with limits specified in 21 CFR or the applicable FCN or TOR exemption.

The different ways to ensure that food contact substances meet FDA requirements are discussed below in more detail. If you have questions or need testing to evaluate your material’s compliance, do not hesitate to contact us.

Using substances listed in 21 CFR

In 21 CFR, substances used to manufacture food packaging and other contact materials are regulated as indirect food additives. The general requirements for their safe use are outlined in Part 174, with further rules specified in Parts 175 to 189.² Manufacturers should refer to the following Parts of 21 CFR to check whether the substances they plan to use have been authorized for the intended use:

• Part 175: Adhesives and coatings

• Part 176: Paper and paperboard

• Part 177: Polymers

• Part 178: Adjuvants, production aids, and sanitizers

• Part 179: Irradiation

• Part 181: Prior-sanctioned substances

• Parts 182, 184, and 186: GRAS substances³

The material-specific parts of 21 CFR list authorized substances and the conditions for their use. These may include limitations on use cases, concentration levels, or transfer to food.

How is compliance testing performed?

Tests to confirm that substances are used in compliance with 21 CFR are typically performed on the finished material in the form in which it contacts food. Unlike in the EU, where specific migration limits are set for individual substances in addition to the overall migration limit applied to plastic food contact articles, FDA tests often focus on the total concentration of extractives removed by a selected solvent. With some materials, final compliance is determined by the amount of total extractives soluble in chloroform. This is the case, for example, for certain polymers listed in Part 177 and paper and board components listed in Part 176 of 21 CFR.

Extraction time and temperature are chosen to match the most severe conditions under which the material will be used.⁴ The most typical solvents are water, alcohol, and n-heptane, which represent different food types and are selected based on the materials' intended use conditions:

• 8% alcohol and 50% alcohol are used to simulate alcoholic beverages with less or more than 8 percent alcohol, respectively; for some materials, only testing with 8% or 50% alcohol, irrespective of the alcohol content, is required.

• Demineralized distilled water is used to simulate non-alcoholic beverages and aqueous foods with no free fat.

• Heptane is used to simulate fatty foods with low moisture content.

• Both water and heptane are used for bakery products and aqueous products with free fat.

• When a food contact material is intended for dry solid foods only, it does not typically require testing.

However, in some cases, material-specific requirements have been set for conducting testing for total extractives:

• Polyolefins (PP, PE): limits for hexane- and xylene-soluble extractives.

• Nylon resins: maximum extractable fragments into water, 95% ethanol, ethyl acetate, and benzene, as well as solubility (or lack thereof) into boiling 4.2N HCl have been set, depending on the type of resin and its intended use.

• Rubber articles for repeated use: limits for total extractives into water and hexane.

As a general rule, total extractives from the food-contact surface should not exceed 0.5 milligrams per square inch (~0.078 milligrams per square centimeter) for the material to comply with 21 CFR.⁵

Using substances authorized under Threshold of Regulation (TOR) exemptions and Food Contact Substance Notifications (FCNs)

If a food contact substance is not listed in a relevant section of 21 CFR, the FDA’s TOR exemption database can be checked to see whether the substance has been exempted from regulation as a food additive. TOR exemptions are granted to substances that are not expected to be carcinogenic or to migrate into food in concentrations above 0.5 parts per billion (ppb). The exemptions apply to the substance in the cleared intended use, regardless of the supplier or manufacturer.⁶

Unlike TOR exemptions, FCNs are supplier-specific. This means that manufacturers of final food contact articles wishing to use substances authorized under an FCN must source the substance from the supplier listed in the applicable notice.⁷ Any additional conditions specified in the notice, such as restrictions on food types, use temperatures, or maximum concentrations, must also be followed.

FDA rules for using PFAS, bisphenol A, and phthalates

Due to rising concerns about potential health risks, the FDA continues to re-evaluate the safety of several high-profile substances used in food contact materials. While these substances are still permitted in selected applications, their use is subject to the following restrictions:

• PFAS: Certain PFAS compounds can be used in non-stick pots and pans, rubber O-rings and gaskets in food-processing equipment, and as manufacturing aids added to other food-contact polymers, as the potential for migration into food is considered negligible in these applications. Use in greaseproof papers has been phased out through voluntary measures, and the FDA has revoked the Food Contact Substance Notifications related to such use.⁸ Several US states have also introduced formal bans on PFAS in food packaging.

• Bisphenol A: The FDA considers BPA to be safe in currently authorized food packaging applications, which include polycarbonate beverage bottles and metal can coatings. Use in baby bottles, sippy cups, and infant formula packaging has been abandoned and is no longer authorized.⁹

• Phthalates: Eight phthalates are currently authorized for use as plasticisers and one as a monomer. In 2022, the FDA denied a citizen petition to revoke the remaining authorizations due to insufficient evidence, but the agency continues to closely monitor phthalate use and evaluate emerging safety data.¹⁰

Is your food contact material ready for the US market?

Measurlabs provides FDA extraction testing according to 21 CFR for a comprehensive range of materials, including paper and board, rubber and elastomers, and resinous and polymeric coatings. While the FDA does not require routine content or migration testing for high-profile substances, such as PFAS, bisphenol A, or phthalates, we do also offer testing to support voluntary claims about their absence. Contact our experts using the form below to request a customized quote tailored to your material and testing needs.