I've wondered if anyone else at work kept a sample of the dust. I never mentioned it to them-- didn't want my door kicked in at 3am by the FBI looking to confiscate contraband.

I figure it contains asbestos and concrete dust, possibly human ash, and who knows what else. And probably some normal dust from before the collapse and from the WTC (I assume there was normal dust in those buildings, too). I've got it well sealed.

I was warning my co-workers to be really careful to not inhale or ingest it, but all I had to say was "It probably contains human ashes" for most of them to pay attention and avoid it. But I was scraping it off and into the trash can. There was so much of it and it was so deep and fluffy.