The process that causes plastic to yellow is attributed to heat, light and oxygen. The combinaton of the three forms yellow-colored compounds on the outer layer of the plasticc. The Retr0bright process seeks to break down these yellow compounds, and should not cause further damage to the plastic, unless the plastic has cracks in it. If the plastic has cracks in it, the internal layer of plastic can be destroyed by the Retr0brighting compound.

The main takeaways:

- Oxygen+Heat/Light causes ABS plastic to turn yellow, so it is best to keep plastic in a cool, dark place. It will still turn yellow, but the process will be slower than if you let it out.
- Before you begin the Retr0bright process, try putting the plastic in the sun behind a glass window for a few hours and see if that helps. Avoid direct sunlight since the UVC will just cause further damage.
- Retrobright should only cause the plastic to become more damaged if the plastic is already cracked.
- Retrobright does not fix the plastic, rather it bleaches it.
- BFRs (Brominated Flame Retardants) contribute to yellowing but aren’t the primary cause