... : Used as food fermentation,detergent ingredient,carbondoxide foamer,pharmacy,leather," ore milling and metallurgy,detergent for wool,exting uisher and metal ... :- 0.07% Insoluble matter max :- 0.01 to 0.05%’ Iron as Fe2O3 max :- 0.001 to 0.002% Heavy Metal ... as PPM max :– Traces Copper as Cu PPM max :- Traces Sell sodium bicarbonate food and industry grade