Hmmm. I'd avoid jobs where there's likely to be gossip and competition, like working in an office full of cubes, for example, where there's chatter around the water cooler and everyone is trying to get ahead by sabotaging their colleagues. Those kinds of jobs where people have to play politics to get promoted, where little cliques form, etc. Jobs where people have the spare time to spread rumors.
I'm in a very practical job right now. Me and my colleagues work as a team towards a single goal. There's nothing to be gained by putting anyone else down.
So I'd suggest jobs where there's a common goal to be reached, where work is busy enough to keep everyone focused on the task at hand. Anywhere that it's not a zero sum game - i.e. avoid places where to get ahead, someone else has to be pushed down (such as anything sales-driven.)
Off the top of my head, restaurant work would be good, anything in public service, government, the arts, manufacturing, education etc.