Jaundice

Jaundice could be an explanation that could possibly be described as producing greenish skin in the children. There are other symptoms associated with jaundice that aren't reported in the case of the children. The locals noticed that they didn't eat a normal diet when they first arrived and rejected the food that was given them. After they got accommodated to their new surroundings and began eating a regular diet, the greenish skin hue went away. That suggests that the cause of the coloration was dietary.