The certification landscape: GRS, ISCC PLUS, food contact, and what buyers should verify

GRS (Global Recycled Standard) certifies recycled content percentage with chain-of-custody through each processing stage, plus social and environmental criteria at certified sites. ISCC PLUS certifies sustainable and circular feedstocks with mass-balance accounting — critical for chemical recycling, where physical segregation of recycled molecules is impossible.

The key distinction for buyers: physical segregation schemes attest that this material is recycled; mass-balance schemes attest that an equivalent quantity of recycled feedstock entered a certified system. Both are legitimate, but marketing claims must match the scheme — and several jurisdictions are tightening rules on how mass-balance claims can be worded on packaging.

Food contact compliance is regulatory, not voluntary: EU regulations 10/2011 and 2022/1616 (for recycled plastics) and FDA regulations in the US define what documentation must exist. For recycled content in food packaging, the recycler's decontamination process itself requires authorization — a supplier claiming food-grade rPET should be able to cite their specific process authorization, not just provide a general certificate.

Declarations of compliance are supplier-issued documents, and their quality varies enormously. A robust DoC specifies the exact regulation, the material grade, tested migration limits, and any usage restrictions (temperature, food types, contact duration).

Every major scheme maintains a public certificate database — GRS via Textile Exchange, ISCC via its certificate registry. Verify the certificate number, scope, and validity dates directly rather than accepting a PDF. Scope matters: a site certified for one process line or material stream does not automatically cover everything the company sells.

For high-stakes applications, audit rights in the supply agreement and periodic third-party testing of delivered material close the gap between what certificates attest and what arrives in the silo.