21 CFR 177

21 CFR Part 177 lists the polymeric materials authorised for use as components of articles intended for repeated or single use in contact with food. It is divided into Subpart B (substances for repeated use, e.g. conveyors, tubing, gaskets) and Subpart C (substances for single-use packaging, e.g. PET bottles, polypropylene tubs, polyethylene films). Each section specifies the resin identity, optional adjuvants and additives, and extractive limits when tested under defined conditions.

Demonstrating compliance for a finished article means matching: (1) the polymer to its 177 listing (e.g. PET to 177.1630, polypropylene to 177.1520); (2) the food type to FDA Table 1 (aqueous, acidic, alcoholic, fatty, etc.); (3) the use condition to FDA Table 2 (A — high-temperature heat-sterilised; B — boiling water; C — hot-fill / pasteurisation; D — hot-fill no further heating; E — room temperature filled and stored; F — refrigerated storage; G — frozen storage; H — frozen ready-prepared) — and then meeting any extractive or migration limit at the corresponding condition.

A Food Contact Notification (FCN) under FFDCA §409(h) is the alternative path for substances or uses not covered by an existing regulation; FCNs are manufacturer-specific. Letters of Guarantee from a resin supplier do not by themselves prove compliance — the converter is responsible for the finished article's use condition.