The bromine is then converted to nitrile using potassium cyanide. Handling cyanide reagents demands high levels of safety precautions, especially when following the large scale pathway, as the amount of cyanide measured is over the dermal median lethal dose (LD50 HCN = 100 mg / kg) of toxic HCN gas that may be produced in case of accidental contact with acid. Some safety precautions include wiping down laboratory bench tops with sodium bicarbonate to neutralize any residual acid from previous steps, wearing two pairs of gloves as extra protection from skin contact, and designating separate waste containers for cyanide waste.