Specifications food grade Assay(as na2h2p2o7)% 95.0 P2o5% 63.0-64.0 Ph value 3.5-4.5 Water insoluble % 1.0 Fluoride (as f) % 0.005 Heavy metals (as pb) % 0.001 Arsenic (as)% 0.0003 Loss on ignition(105µ) % 0.5 Packed in 25 kg, 50kg, 1000kg net bags, store at a cool, dry and well ventilated place.