According to Cshenk :

"mike" wrote

If I'm ever coming down with hypotheria, I'll be sure not to burn
driftwood because the EPA says so. Never means never.

I was kinda wondering about the driftwood....

I can't see a reason to not use it unless it's on the edge of a chemical
dump or something.

I did a bit of googling, and saw:

http://www.env.gov.bc.ca/air/particulates/rwssabi.html

The more significant rationale seems to be that driftwood on ocean
beaches is laden with salt. Entirely aside from the mentioned
potential of dioxin/furan production, chlorine ions and heat will
accelerate the corrosion of metal stove or venting systems, and
aren't terribly good to be downwind of either.

But they're unlikely to get too terribly bent out of shape if
it's an emergency to avoid freezing to death.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.