Testing Whether Fungi Can Grow on and Break Down Plastic

What I’m working on:
Testing whether fungi can grow on plastic and potentially break it down

My goal:
To see if fungal growth can contribute to plastic decomposition

My setup / approach:
I placed small pieces of plastic in a damp environment where fungal growth could occur

I did not isolate a specific species, but I observed naturally occurring fungi in the setup

What I’ve observed so far:
-After about a week, I saw fungal growth forming on the surface of the plastic
-The plastic itself did not visibly change or break down

What I’m trying to figure out:
Whether the fungus is actually interacting with the plastic in a way that could lead to breakdown, or if it is just growing on the surface

Specific feedback I’m looking for:

  • How to tell if plastic is actually being broken down
  • Whether I would need a specific species (like Pestalotiopsis microspora) to observe this effect