Where as the oil and gunk you are taking off these parts, mixing in with the HCL and converting to some sort of salt, CAN be harmful.

Sounds like you havn't used this before, i have to remove oil,grease, undercoating,"crud" before i dip the part in. I put that stuff on the highway with every other cars " crud". When done i put the acid solution back in plastic containers to use again for the next rusty part, to expensive to throw away. You guys can save the planet, i'll get the rust off my way.