You can always repot the plant when you get it home. There are organic soils available that do not have fertilizers or perlite in them. Take the plant out of its pot, wash as much of the soil out as possible, and repot with clean soil. At the same time wash the leaves and stems of the plant to get any yuckiness off. It is good to then put large stones over the soil so the chameleon doesn't accidentally eat soil while hunting stray prey items. I recently found some really nice organic potting mix that was labeled with the miracle gro brand.