Subject: what gases are given off during electrolysis?

Hi,  I have begun using electrolysis to clean some old rusty and 
crusty artifacts.  It's a pretty low key affair using an 8volt adapter 
from a Black and Decker drill with an aligator clip (chrome-over 
copper) and the negative lead attached to a stainless steel spoon.  I 
clip an old crusty coin (copper) to the positive lead and the suspend 
it in a bowl of water. The stainless steel spoon is then suspend close 
to the coin and I add salt and lemon juice for the electolyte.  I  am 
wondering...what gases are given off during the bubbling of the 
electrolyte considering all the differant metals used and the 
combination of salt and lemon juice.  Is the gas hazardous?  I also 
use the same process on iron "grapeshot" and other ferrous metals.  It 
really does bubble like crazy and I am careful to provide adequate 
ventilation...but was curious just the same.  Thanks in advance.  
Thomas

Re: what gases are given off during electrolysis?