Calcium carbide
Dipping mangoes in 2% sodium carbonate solution for 12 hr can be used to remove arsenic residues from the calcium carbide ripened mangoes prior to their consumption.
Detection
Mango fruit starts to get black patches in 2 to 3 days due to the usage of calcium carbide for ripening of Mango fruit. Traces of white color powder arsenic traces are found on the mango fruit; if Calcium Carbide is applied, there will be traces of arsenic powder white powder.
“Put the mangoes in a bucket of water. If the mangoes sink, they are naturally ripened. If they float, they are harvested artificially. Also, an artificially ripened mango will have very little or no juice dripping out."