Kitchen wrap and common plastic bags are made out of polyethylene.
There is no chlorine in their chemistry, and so are inert. They won't harm your coins.
PVC is anopther matter It is poly vynyl chloride and as the name suggests, has chlorine in it's chemistry. There is also a softener in pliable clear PVC, which can gas out over time. Both of these components in PVC can be injurious to coins.
Hovever, even PVC can be used for temporary storage of coins, but I do NOT reccommend PVC as a material for long term coin storage.