Posted by Gerald J. on July 15, 1999 at 23:11:02:
In Reply to: Cyanide Warning: Mouthpiece Plating posted by Brett W. on July 15, 1999 at 22:26:16:
Plated metal is held by the same atomic forces that hold a solid block of metal together not by any chemicals other than gold from the plating solution. Cyanide is a component of many plating baths because it tends to result in a plate less likely to peal than alternatives. Gold is hard to plate.
The hazard is from any cyanide in any pores in the plating that hasn't been washed well. Its water soluble so a good hot water wash (dish washer isn't out of line) should remove any cyanide residue from the mouthpiece.
Cyanide is a poison though 50 or 60 years ago, platers judged the chemical composition of such plating baths by tasting them. They didn't live to a ripe old age that way and they did damage to their faces because the other strong chemicals in the plating baths.
A good analytical chemist should be able to test the plated (and washed) mouthpiece for cyanide residue for less than the cost of a new gold mouthpiece. The plating shop shouldn't have plated a mouthpiece in a way to make it hazardous to the user's health so ought to replace the mouthpiece if it can't be cleaned.
Look in the Merck Chemical Index for details on cyanide safety.
Gerald J.