I'd have to say crime scene cleaner would have to be up there. I'd imagine the psychological toll would be tremendous.
Why i picked that as one of the jobs, mystic, is because I saw this prank call video on youtube, where the guy called a suicide hotline, and the girl picked up and just sounded so miserable, kinda like she just got done crying. It was a hard prank video to watch...
Telemarketers would have horrible jobs too. They are made out to be the bad guys of the landlines, and are also the butte of a lot of jokes, and their temper tantrums are sometimes featured on youtube.
One of the worst jobs I know of are a telemarketer and a door-to-door salesman/saleswoman. Telemarketers are generally disliked by the general population and get hung up many, many times a day. Door-to-door sales people must face the rude comments of "Get off my property" and have the door slammed in their face.
I pity them
Fast food crew worker.
You are around greasy food all day. The grease starts to get over your clothes and skin.
Dead-end job, you do not have much opportunities to growth within the company. (Expectation; maybe you can be come a manager in 5 years staying at the job).
This is the worst job in my opinion and experience. I have worked at fast food for 6 months and could not take it.
But you know what's actually a cool minimum wage place to work at? Jamba Juice, or Baskin Robins. I love jamba juice, because of their juice smoothies, plus, if I got a check, I would spend it there first XD
Same with basking robins, but I just love the whole feel and smell of the place, like walking into ice cream world or something. Such a happy atmosphere.