Never touch anything in a subway station. Never lean on a column, sit on a bench, or, God forbid, do a pull-up from a rafter. Subway stations have been coated with a hundred years of filth. Brake dust, rust, flakes of lead paint, rotten food, rain water drained from the street, dog piss, rat piss, human piss, vomit, all kinds of fecal matter from all kinds of sources. There's no reason to believe the rare occasions when things are sprayed and scrubbed down that everything is cleansed. Even the smell of the air, a truly unique odor, tells one all they need to know about the tunnels. In the cars, it's different. There are three options. Sit on a dirty seat, a thin layer of clothes between you and the plastic; hold onto a metal bar; or surf, holding nothing and risking falling on the floor, which is just as bad as lying on the track bed in some cars. In fact, the ideal situation would be to ride the subway in a deep sea diving suit which, upon exiting, is dipped in gasoline and set on fire.