While the game's nicely done roguelike anti-scumming measures stop most trickery... (for those not familiar with the terminology, 'save scumming' means saving and reloading to get a better outcome than what happened the first time).
... it's still possible to do some very basic scumming that nevertheless comes in handy. Potion identification - er, excuse me, BIOMOD identification, hehe - is a scary part of any fun roguelike. But given the scarcity of good gear for the majority of the game, sometimes a bad biomod REALLY hurts your game. Same goes for your character's biomods. Can you afford those -2 stat mods? Maybe not!
Luckily, there is one way that you can, if you are very methodical about it, get a do-over on having installed or taken a bad biomod. I've only tested it in Windows 7, but if you do -absolutely nothing- after taking or using the bad biomod, you can ctrl+alt+del and kill the task via the Task Manager and the game will not have saved the bad biomod's intake. What's more, since biomods are seeded at the start of the game, when you reload and have undone your goof, you'll know better than to use that bad color... for the rest of that run, anyway.