It was released into the air. The particle size is a few microns. This is real fine dust that is suspended in the air for days at a time. When the envelope is opened a certain amount escapes because it is so fine. It squirts out like smoke.
Huge amounts of mail might be contaminated from just a few leaky envelopes with small perforations. This is real bad. If you don't want everyone to know what your doing in this respect they might mail letters to themselves at a PO BOX where it wouldn't be discovered. The leaky thing would spread this stuff everywhere it went. The mail system is in a fact a huge distribution source,lets face it!!
Irradiate all mail. Sterilize the $hit out of it. We have the technology.
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