How to clean a "plastic" chopping board?
Stick it in the dishwasher.
A short soak and a stiff brush.  Then some disinfectant of what kind you use, let it soak for a bit, then rinse off.


If you're not able to get your plastic clean reliably, you're better off with a good wood board. Some research shows that they're more naturally anti microbial.



Based on your comment

It sounds like a good 'wooden endgrain board' may be in your future.  When well cared for, they 'self heal'.  The knives don't leave deep groves when used properly and they're somewhat anti-microbial according to the earlier link.