My workplace's environment is not healthy?

It's best to ensure the tension doesn't spread to yourself. Show dominance over the wider pack by peeing all around your work area to show that it is yours. Ensure you have the first bite of any lunch they bring in. Jealously and aggressively defend your own resources, tools, stationary, what have you. Fashion rudimentary weapons such as a sharpened chair leg, or one of your socks full of wet sand.

Sow dissent by spreading rumours between the warring factions until they eventually take up arms against one another. Then pick off and eat any survivors, mate with the manager and the workplace will be yours.

Or keep your head down and quietly look elsewhere for work in the meantime, either/or.