When I was in college, we managed to break a mercury barometer. Scattered about 5 lbs of mercury all over the floor. It was stuck in every crack in the linoleum, etc you could imagine. We just swept up as best as possible and dumped it in the trash. Many of us spent 8-12 hours a day, every day, in that room. To the best of my knowledge, we are all still alive and well 30 years later.
Needless to say, I’m not worried about breaking a fluorescent bulb.
And mercury is cumulative, slow, subtle and indirect in its affects.
I was a fussy eater as a kid and would carefully clean any obvious dirt off the food I ate. My dad would snort and tell me that you got eat a peck of dirt before you die. I would reply "but why hurry the process up?"
Take what precautions your circumstances and temperament allow, live as well as you can, until you're as dead as can be.