I have seen such a test before, but I think the actual danger can be decreased dramatically if the printer is operated in an environment with good air conditioning, especially, ventilation. I remember the printer room of the met offices has always been very aggressive on my eyes and lungs from the emissions of the printer and plotter equipment there, and the chemicals used in those.
The problem with judging the results of these tests is where the measurements have been taken. In the test I saw, the measuring probe was closed near the exit of the printer, where the dust particle count was soaring. I may doubt this is the load an office worker inhales, at least I have never seen someone put his nose into the printer. As long as I don't know how this test was being conducted, I would be careful with acting on its results.