Hooked on phonics. I hear it does wonders for stuff like this.
Any one can guess about any of this stuff.
But to present mere guesses as “fact” is misleading and confusing.
My favorite guess is this....
If the guy loaded the envelopes in a house or apartment, there should be some spilled or leaked anthrax that should infect other people in the vicinity sooner or later. But if he loaded the envelopes in a special science lab, there might not be any spilled anthrax at all.
As to whether or not the anthrax is from here or Iraq, or whether or not the guy is an Arab or an American nutcase, there is not enough information yet.