The people downstairs are bug bombing there apartment, is we safe upstairs from the poison?

It depends how much they are using. If there is the tinyest crack in your ceiling, or you can smell it I would open the windows more often and ask them to not use so much not only is it there health there hurting its everyone else's including the environment. MORE DETAILS PLEEEEEASE.

As long as they are using the approved pestisieds, you should be OK. Just open your windows and air it out. You should find out why they are bombing? I would be more concered with what there trying to get rid of, and hope you don't get it.

Unless it is an unusually tight building some is going to leak into your apartment. It should stay low. Be careful of children and pets. If they regularly do it without warning you, I would talk to the landlord.