The conflation of droplets with actual particulate matter and its harmful properties seems to trace back to gross negligence rather than malice. Researchers whose favorite equipment cannot detect the difference between liquids in solids in aerosols mistakenly reported seeing “particulates” in the vapor. (E-cigarette “vapor” is really mostly an aerosol, not technically vapor.) Users of such equipment tend to refer to both particles and droplets as “particles” because both look the same to them. That does not cause much trouble until they port this language, and their inability to distinguish, to a health context. There it is extremely misleading.
Read more: http://dailyvaper.com/2017/11/13/science-lesson-vapor-droplets-are-not-particles/