That would explain! I'm not yet a factorio veteran, and I posted this because I downloaded the 16.35 beta today. I guess this topic is up for closing . Thanks for the fast reply

I noticed the pollution factor going up way more than the promised +10% while adding two productivity 3 modules in my centrifuge.
Base pollution centrifuge: 5.6
One productivity 3 module (+10%): 11.088
Two productivity 3 modules (+20%): 17.472