I made a MONSTROUS mess back before I got smart enough to know how to operate a gravel vacuum so YES - I sucked on the end of it. Well, as not smart as that was, it was even not smarter when I started getting water in my mouth to yank it out of my mouth, water was still coming through it AND I spit all the water from my mouth all over the couch.
So as if I didn't have enough of a mess already... I was romping around trying to get to the kitchen to wash my mouth out with water and I stepped right into the bowl that I had thrown the end of the vacuum into and there was water in it.
Come to think of it, I have never told anyone that story before.
lol