There have been two room air quality trials on ecig vapor so far. Neither could find measurable amounts of anything in the room-size chamber they used. One found nothing they could measure, the other found traces that were not reliably quantifiable. As a result they both changed to using a small container for the exhaled air tests, one of them was a 10 litre container IIRC.
They found measurable quantities of compounds when vapor was basically exhaled direct into their test equipment, but not in free airspace in a room-size chamber (10m2 I think). This infers that solids quickly deposit out of the vapor; and that to get any 2nd hand materials you need to be kissing the vaper on exhale. This is a cheap way of vaping but better results are obtained by buying your own supplies.
One study was an 'open' one where they just reported the results, the other was funded by the antis, so they buried the fact they found nothing measurable in the room air deep in the small print and instead used results taken from measurement of direct-exhale vapor. (Then of course published a lurid PR implying ecig vapor is dangerously toxic, as per normal.)
As regards the quantity of nicotine you would be able to breathe in from room air where a vaper was situated, it would result in an increase of your blood plasma nicotine level between ten million times and one million times lower than the detectable level already present from your normal dietary consumption of nicotine. This is my personal estimation based on about as much scientific evidence as is usually present in any report by Glantz, Hahn, Gratziou or any other pharma pimp / loony toon.
Refs: seen elsewhere on ECF, in CASAA resources, etc.