As time has gone by and I have become quite familiar with these compounds, I have most definitely licked up some powders that resulted from transferring substances and other such activities. I would not do so with something like DOC, where a tiny bit of powder could be full dose, though. But as far as 2C-phenethylamines, 4-sub-tryptamines, and other moderately-dosed chemicals, I've definitely ingested ~1-2mg or so, as a total estimate, in addition to my planned dose, or when sober (on very few occasions, where I knew the powder in question was between just a couple of things, none of which could harm me in such minute amounts.
Although, no, I have not accidentally tripped this way, only had minor alteration if anything at all. And I don't want to make it sound like I leave psychedelic powders laying everywhere either! It's just that when you've dosed out so many times with the same scale on the same desk surface, many times while already on something, you tend to lose tiny particples, and sometimes it's enough to notice.