If anyone lost a whole heap of sea urchin spines, please contact me. I found plenty of them while chasing a mates kite when his line snapped after I ran into them.
If you want them returned, feel free to bring tweezers along to my house and dig them out of my foot. [}:)]
If you can't pull them out get some cotton balls and soak them in vinegar then tape it over the spines in your foot, that desolves the spines after about a day. Repeat every few hours. If they're not disolved it will still make it much easier to pull them out. 2 days later you'll be fine