I don't know, but I made an utter fool out of myself (the family doesn't know) a few weeks ago, when I saw a jerry can that had been sitting by the side of the road for several days where I'd been passing it. Reasoning that it had been abandoned, I stopped to get it, then found that it had about a gallon of gasoline in it, but I still wanted the can (I have several). I left it in my trunk a few days, and lo and behold, my new Camry reeked of gasoline. I had to air it out good and proper to get rid of the smell. I don't know if the gas is any good, don't know what it's got in it, to my untutored abilities, it could even be diesel, I wouldn't dare put it in one of my cars, so it is just sitting out there. I can't dump it anywhere (legally or morally, that is) so I'm going to have to drive halfway across the county to the waste disposal center one of these days, have them pour it out, and get them to give me the can back, so I can rinse it out and reuse it. I could have bought one of those cans, for what the gasoline will cost me to drive out there.
Moral of the story: don't pick up an abandoned jerry can of gas unless you have a plan for getting rid of it with no expense or inconvenience to yourself. Stupid wins again.