Either way not a cool thing to suggest! Thanks for the clarification.
After re-reading the thread I think I misinterpreted some posts.. Fob Magi wrote only to toss them in the fireplace "If you want to live dangerously", then Phant84 wrote further down "Since someone already said fireplace....My father-in-law said they should be safe." He meant that since someone else had already mentioned living dangerously firing the old cartridges was less dangerous than throwing them in a fireplace. I thought he meant that his father-in-law said it would be safe to throw them into the fire. Whups, forget I posted in this thread.