Coconuts are very porous and anything put on them (e.g. chemicals) soak into the coconut. Antifungals and Formaldehyde have both been associated with coconuts, being used to prolong the life of the coconut during shipping. I don't know about you, but I don't want these things in my diet!
Check out this video for some more information about regular coconuts and an experiment that was done which seemds to quite clearly indicate just how permeable the coconuts are.
For our future Pot Lucks I am adding Organic Young Coconuts to the Raw Faerie Shop. If you would like to order a coconut (or a few), for collection at the pot lucks, then let me know. Coconuts cost £3.01 each <3 <3 <3