This isn't the worst job I've ever had.
The worst job I've ever had (and there are many contenders; I might mention litter-picking after Party in the Park, I might mention being a files clerk for the National Lottery Charities' Board) was being a machine-minder in a hinge factory. It bit.
I had various duties but mainly I was assigned to operate one or other of the several drilling machines that drilled out and countersunk each leaf of the hinge, ready to be assembled elsewhere in the factory. (The technical term for what I did was "reaming knuckles". No, really.) My job consisted of placing each leaf in turn in the machine, then pressing a button to operate the drilling mechanism, then taking out the leaf and blowing all the grot off it with an air-hose. Becuase the drill-bits would get very hot they and the leaf had to be bathed in a constant stream of coolant fluid, a thin, milky liquid with a greasy mineral odour. Swarf piled up everywhere, corkscrews and flakes of sharp metal.
The permanent staff were given thick long-sleeved overalls but there were not enough spare ones for the temps. That's pretty typical; when it comes to protective gear, temps and casuals generally get stiffed. This happens in plush offices as well as the factory floor-- you wouldn't belive the number of times I've temped in a huge swanky building for a company whose budget seemed to cover logo-adorned carpets and marble surfaces but not an extra chair, so that temp workers were expected to spend eight hours standing up to type. I have permenant nerve damage in my right arm and shoulder from such practices.
As a temp, I had not an overall but a disposable apron made of thin blue plastic. Someone also found me a plastic sack which I could lay across my knees while I worked. These did not suffice to keep the coolant and swarf off me, however; after ten minutes at the machine my clothes would be saturated with coolant, my face and hair splashed with it. The coolant was nasty stuff. It dried out my skin so that it became coarse in texture and it triggered an allergic reaction which made me itch wherever the liquid got on me-- and it got on me everywhere. I was red and itchy from head to toe, all the time. The discomfort used to keep me awake at night. The swarf was also a problem. It got into my clothes, insinuating itself into the fabric. If I pushed back my sleeves without thinking, it would cut and scratch the skin. I looked like a Slipknot fan.
Thick red rubber gloves were supplied freely. The coolant would react with the rubber, making it stiff and brittle. Eventually it would crack, allowing swarf and coolant onto your hands. The stiffness also meant that handling the leaves became tricky. Since there was always somebody overseeing the work, shouting and demanding more speed, I would sometimes have to remove one or both of my gloves in order to keep up with the pace demanded.
Insert the leaf, press the button, remove the leaf, clean it, put it in the tray. Insert the leaf, press the button, remove the leaf. Insert the leaf, press the button, remove the leaf. I got through about four thousand a day, most days. It's easy, when doing this kind of work, to drift off into a trance state. Easy-- but risky. There were all kinds of eventualities demanding the operators attention: steam from an overheating drillbit, countersinking becoming too deep or not deep enough, a change in the din from the machine indicating some sort of problem. Drift off and you can make mistakes, mistakes that might end up costing you the booking. Unsatisfactory work. The employer can turn round and refuse to pay the agency for your labour; the agency will think twice before offering you work again. Even if they don't boot you out for good and all, they aren't obliged to find you work. So. Focus. Insert the leaf, press the button, remove the leaf. No matter how bored you are, no matter how much you might want to let your mind wander, you must stay in the here-and-now. You must insert the leaf, press the button, remove the leaf. Check every tenth one for damage and dodgy countersinking. Insert the leaf, press the button, remove the leaf, all day, four thousand times a day.
Minimum wage, natch.