My brother found a glowstick once at Disneyland, as a kid. It was in the planters, on the ground.
He didn't realize until it was too late that it was a broken one and his 10-year-old face was ALIVE with the glowy sauce, even in his eyes.
Of course, this stuff is all non-toxic, so he was ok, but man, seeing him come out of the bushes all glowing was nightmare inducing.