1. Introduction

The United States is among the countries with the longest history of regulating food contact materials globally. In 1958, the Food Additive Amendment to the Federal Food, Drug & Cosmetic Act was published, enabling the U.S. Food and Drug Administration (FDA) to ensure food safety by regulating food additives.

Food additives can be added to food directly or indirectly. Substances in products such as food packaging, utensils and food processing machinery may become trace components of the food they contact with through migration, and are considered indirect food additives according to U.S. law. Since then, such substances (i.e., food contact substances) have been categorized as indirect food additives under FDA regulation and require FDA approval before entering into the U.S. market.

The term Food Contact Materials in a broader sense can be divided into three levels:

• Food Contact Substance (FCS) refers to any substance used as a component in materials for manufacturing, packing, packaging, transporting, or storing food, without any technical effect on the food itself. Food contact substances are individual substances, such as antioxidants.
• Food Contact Material (FCM) is made from FCS and other substances, usually (but not necessarily) a mixture, such as a polymer containing antioxidants. The composition can vary.
• Food Contact Article refers to finished products made from FCM, such as bottles, packaging bags, trays, etc.

Thus, FCM involve products produced across multiple levels of the supply chain, with each operator bearing corresponding responsibilities and obligations. This article will focus on the U.S. FCM regulatory model and compliance method, aiming to assist enterprises in product compliance.

2. Legislative System

2.1 Federal Legislation

Federal Food, Drug & Cosmetic Act (FD&C Act) provides the fundamental principles and main framework for food safety management in the U.S., granting the FDA the authority to regulate food safety.

Under the principled provisions of the FD&C Act, the FDA has compiled Title 21 of the Code of Federal Regulations (CFR), serving as a specific regulatory extension to the Act. Regulations related to the FCM are primarily in sections 170-189 of Title 21 CFR (referred to as 21 CFR 170-189), which specifies standards for FCM (such as specifications, limits, and usage requirements) and the conditions that various types of FCM need to meet (such as categories of food contact, index requirements, and testing conditions).

Furthermore, the FDA also issues Compliance Policy Guides (CPG) and Guidance for Industry to provide guidance on issues that lack a legal regulatory basis. For example, for imported silver-plated tableware and the leaching levels of lead and cadmium in ceramic and glass products, the FDA has specified related limitations and testing methods in CPG.

2.2 State Legislation

For the state legislation, laws related to FCM include the Proposition 65 published by California and the Model Toxics in Packaging legislation formulated by Northeastern states, among others. Therefore, FCM in specific state markets also need to comply with the requirements of state legislation.

3. Regulatory Mode

As previously mentioned, FCS are subject to indirect food additives and are regulated by the FDA. The overall regulatory method for FCM is determined by the regulatory status of each FCS that constitutes the product. Hence, individual substances in food contact articles that migrate to food under their intended use must meet one of the following five categories.

3.1 Indirect Food Additives Approved by FDA

The FDA has formulated a list of substances approved in the production of FCM (including monomers, additives, adjuvants, etc.) in 21 CFR 174-179, which includes materials such as adhesives, coatings, paper and paperboard, polymers, rubber, etc. This list also specifies the chemical specification, purity, usage limits, and safety guidelines for the approved substances.

This list covers most of the FCM on the market, meeting the specifications and restrictions under the regulations without the need for further FDA approval. Substances not in the regulations or not meeting the requirements shall be further assessed to determine if they qualify for exemption from approval.

3.2 Prior-Sanctioned Substances

Before the official inclusion of food packaging under FDA regulation in 1958, the FDA had already approved certain substances and their specific conditions of application in response to manufacturers' inquiries about food packaging. These substances, approved before 1958, are known as prior-sanctioned substances and do not require pre-market approval from the FDA anymore. The list of prior-sanctioned substances can be searched in 21 CFR 181.

3.3 Generally Recognized as Safe (GRAS) Substances

GRAS substances refer to those assessed for safety by qualified experts through scientific training, and are widely considered safe under the conditions of their intended application. According to the regulations, substances recognized as GRAS under their intended conditions of application are not subject to food additives and do not require pre-market approval from the FDA.

The exemption from approval for GRAS substances is effective for all manufacturers. The list of GRAS substances can be searched in 21 CFR 182-186 and on the FDA website under GRAS notices.

3.4 Threshold of Regulation (TOR) Exemptions

TOR Exemptions are for FCM that are not known carcinogens, do not affect the food, do not damage the environment, and have daily dietary concentrations not exceeding 0.5 ppb, exempting them from pre-market regulatory approval requirements as food additives.

Substances approved by the TOR Exemptions review are published in the TOR Exemptions list on the FDA's official website, which includes the substance name, specific application and corresponding application restrictions. TOR Exemptions are broadly applicable. All manufacturers and suppliers can use or sell TOR Exemptions substances under the same substance characteristics and intended applications based on the list.

3.5 Effective Food Contact Substance Notification (FCN)

The list of effective Food Contact Substance Notification, reviewed and confirmed by the FDA, can be queried on the FDA's official website. The list includes information on food contact substances (FCS) such as names and CAS numbers, manufacturers or suppliers, intended uses, restrictions and specifications, effective dates, and their environmental impact statements.

It is important to note that an FCN is only valid for the manufacturer who submitted the notification and the substance in question. If other enterprises wish to use the substance listed in an FCN, they must submit a separate FCN or purchase the substance from an enterprise that has completed its notification.

4. Compliance Declaration Path

If a food contact substance is not subject to any of the above categories, compliance can be pursued through the following application process:

4.1 Food Contact Substance Notification (FCN)

Any substance defined as a food contact substance (except those with a daily dietary intake concentration exceeding 1 ppm) can request FDA assessment and approval for its use in food contact through the FCN process. The statutory technical review period for a FCN is 120 days. If the FDA does not issue a non-approval within 120 days, it means the notification is effective and will be published on the FDA website. 

The FCN application must include sufficient scientific information and data to ensure the safety of the food contact substances for its intended use.

Data requirements:

4.2 Threshold of Regulation (TOR) Exemption Notification

If the substance's daily dietary intake concentration under expected conditions of use does not exceed 0.5 ppb, enterprises may submit a simplified TOR exemption notification to the FDA, requesting the substance to be included in the TOR exemption list. Although TOR exemption notification is similar to FCN in procedure, due to the low daily dietary intake concentration, the data requirements for TOR exemption notification is far less stringent than those for an FCN. For example, toxicological data is not required to demonstrate the safety of the substance at low exposure levels.

4.3 Generally Recognized as Safe (GRAS) Notification

Any individual or organization can submit a GRAS notification to the FDA, declaring that a substance is subject to GRAS substances. After FDA evaluation of the GRAS notification, if the applicant receives a "No questions" letter, it means that the substance has been included in the FDA's GRAS notification list and can be searched on its official website. Generally, GRAS substances that have been officially notified have authority and are more widely recognized.

5. Letter of Guaranty

The Letter of Guaranty is an important document throughout the multi-level supply chain of food contact materials. It helps enterprises effectively convey compliance information downstream while ensuring the traceability of information transmission for food contact materials.

According to Section 303 of the FD&C Act, anyone who receives a letter of guaranty from an upstream source will not be penalized for receiving or providing adulterated or misbranded food additives. Therefore, although the U.S. FDA does not mandatorily require enterprises to issue compliance statements for their products, downstream customers may request manufacturers to provide a letter of guaranty along with their shipments to certify the compliance of the food contact use of the products they purchase.

6. Summary

Based on the above content, the following diagram summarizes the compliance assessment and response methods for food contact materials before entering the US market.

Throughout the entire supply chain of food contact material, all levels of suppliers shall pay attention to compliance control requirements for products and bear corresponding responsibilities and obligations:

• Chemical substance manufacturers producing food contact materials shall be aware of whether the substances have been approved by the FDA, ensure that their quality specifications comply with regulations, and provide downstream parties with substance safety information, regulatory authorizations, and usage restriction explanations (Letter of Guaranty) when necessary.
• Intermediate material manufacturers shall verify the qualifications of raw materials (such as requesting Letter of Guaranty from upstream raw material suppliers) and ensure that products comply with relevant specifications for food contact materials in the US. When necessary, they shall disclose product usage restriction explanations, compliance of raw materials and additives, and substances with restricted requirements (Letter of Guaranty) to downstream parties.
• End-product manufacturers can request Letter of Guaranty from upstream suppliers and ensure compliance with US regulations through various aspects such as raw materials, production, and finished product testing.