Our L- Threonine has been certified by HACCP FOOD SAFETY MANAGEMENT SYSTEM and FAMI-QS .And the quality of Itaconic it conforms to the standard of Iwata Chemical Co., Japan and standard of Ajinomoto Japan respectively. Name: L-Threonine(ß-hydroxyl-aaminobutyric acid) CAS NO: 72-19-5 Molecular weight: 119.12 Specification Appearance: White or light-brown crystal or powder Loss on drying: 1.0% Max Residues on ignition: 0.5% Max Assay: 98.5% Min Specific rotation: -26.7 -29.6 Heavy metals: 10PPM Max Arsenic: 2PPM Max PH: 5.0-6.5 Packing:25kg in a compound bag.