Lead, kinda scary stuff.
Back in the 80's I worked at an GM/Delco battery factory when I was in college. A great paying job with full medical benefits, very tough to get a job there. The only downside besides the mind numbing repetition of assembly line work (brutal), was the danger of lead poisoning.
They told us it was perfectly safe and they gave us regular blood tests to monitor our blood lead levels. If its so safe, why do we need to have our blood lead levels regularly checked? Lol.
There was also the constant smell of battery acid, its was everywhere, even in the offices, you could smell it in the parking lot. Remember thinking, that doesn't seem too healthy.
It was a strange place to work, I remember the charging dept was the place to be, they sent down hundreds of batteries at a time to be hooked up to chargers. The guys would hustle through them all, get them hooked up, then they would lay down and take naps until the next batch rolled down. They would take turns being on the lookout for supervisors.
I lasted about a year, as far as I can tell, no residual effects, thank goodness.