The dust samples from the interior and roof of the Bankers Trust building was deposited by the dust clouds from the collapses of the towers. Any microspheres from the "cleanup" would not have been spread as the WTC collapse dust was.
The R.J. Lee Group said: "Various metals (most notably iron and lead) were melted during the WTC [FONT="]Event, producing spherical metallic particles."
ETA:"[/FONT]Particles of materials that had been modified by exposure to high temperature, such as spherical particles of iron and silicates, are common in WTC Dust because of the fire that accompanied the WTC Event, but are not common in “normal” interior office dust."
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You think you know more about it than they do, you do not. You are in denial and you are groping for alternate explanations. The iron spheres in the WTC dust were also in the 35 samples gathered by the USGS a few days after the event.
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