Chinese drywall gases?????

In a crawlspace I found copper piping oxidized black (looks like a blacked shotgun barrel) please see pics.
With the info I have on chinese drywall this has raised concern over what is causing this in the crawl (the is no drywall).
Has anyone seen this before? I have not. I am concerned with the life of the piping and with the health of the client.
Thanx in advance.




When was the house built?

If it was not built during the chinese drywall era I would suspect some mold cleaning chemicals have been used or spilled in the crawlspace.

Check this post out…

Bruce, I was not truely suspecting drywall. No drywall near it and 1988 home. Black piping and wiring in drywall is an indicator of chinese drywall. My mind extrapolated this might be caused by some toxic or radioactive gas as with chinese drywall. I’m not sure of the electroysis explaination, but it seems to be the consensus and is as good an explianation as any. I’m just happy if my client is not being exposed to someting dangerous. Thanks to David and Andy for the links.:smiley: