USP- or food-grade glycerine intended for pharmaceutical, food, or personal care use may be subject to FDA review as an excipient or food additive ingredient, and importers should be prepared to provide certificates of analysis confirming purity (typically ≥99.5% glycerol), heavy metals limits, and absence of contaminants. Crude or technical-grade glycerol from biodiesel production faces no such review but may carry methanol residues that require disclosure in the SDS.

Glycerol is generated as an unavoidable co-product of biodiesel transesterification — roughly one part glycerol for every nine parts biodiesel produced. Expansions in biodiesel capacity, particularly in Southeast Asia and Europe, have periodically flooded the crude glycerol market, depressing prices for technical grades while refined USP glycerine prices remain more stable due to purification costs. Importers sourcing crude glycerol should monitor biodiesel policy changes in major producing regions as a leading indicator of supply availability.