I think it definitely could be toxins from 9-11. It is amazing what the body will purge up during a MC.
I posted several MC's ago about my experience with a toxin release of crank (if you don't know what crank is, it is speed, aka methamphetamine, a cocaine-like substance big in the 1980's and still big in the midwest) - on about day 5 or 6 of I think my second MC, sometime late last year. I swear I could taste it in the back of my throat and I even felt a little bit of the effect of it. The last time I "did" crank was back in 1985, although I've done other illicit substances since then (nothing at all other than tobacco since summer 2001, though).