"I saw a post of a guy who took
K-30 and 18-55 WR to burning man. His camera survived. But I'm sure these food coloring powder particles are smaller than what ever a dust storm can do."
Well, I would argue that the Burning Man dust (4th Burn upcoming) is just as fine as color run powder and my gear has been just fine after a little TLC and caution. See also all the great Burning Man photos by Tray Radcliff at Stuck in Customs website.
I think my main concern with Color Run is now about fire safety after what happened in China last month where the fine powder ignited amongst the crowd. Pretty nasty outcome.