http://www.dkfz.de/en/presse/download/RS-Vol19-E-Cigarettes-EN.pdf
Above is the article the FDA based their notice on. It is nothing but inuendo and weak supposition as to the health effects. They also do not give any methods used but based on my experience with US regulatory agencies they probably used high capacity air filters to concentrate whatever was in the air for analysis. They would need to do that to even detect it since the conc are so low. We are probably dealing with trace amounts in the air.
That does seem to be pushing it, as unlike the normal cigarette, it only emits where it is desired.