I peeled the plastic off of a young coconut in order to crack it. i later learned that they are bleached with pesticides. should i be concerned?

No: Your exposure is minimal no reason for concern.

Pesticides: I would not be very concerned, unless you eat tens a day..I would wash my hands. Unfortunately many of our fruits and vegetables have pesticide treatment. Wash them and you hands well.

No: Just wash your hands right after. You may wash the coconut shell as well with a mix of white vinegar and water prior to cracking the shell. Because of its shell, I doubt it pesticides or fungicides/ chemicals are detected in the coconut water.