The paper still stands. There has been quite a bit of research activity in this area.

Anecdotally: my lab recently got a Brother laser printer. There was an odour after printing so we tried the experiment (using the same air quality equipment). Sure enough, we saw huge UFP peaks.

Recent developments: UFP emissions from 3D printers http://www.sciencedirect.com/science/article/pii/S1352231013...