The other day I acquired some vintage bottle openers (they look like the one in the pic). They were kind of rusty, and according to the interwebz, white vinegar can be used to remove rust. So, I threw them in a tupperware and covered them with vinegar. And then I kind of forgot about them until today. The liquid that is in there is no longer clear; it's well, rust-colored with some black blobs. Is it okay to dump this liquid down the drain or did I inadvertently create hazardous waste? The plastic of the container seems to be unaffected, so I'm guessing the liquid is harmless, but I don't want to dissolve my pipes or anything. TIA.

ETA: Thanks for the replies. I dumped the goop down the kitchen sink and nothing exploded. Here are the openers I was cleaning:

I'm not sure what happened to the bottom two. They turned black and there are a few flecks of gold on them. Oh well, they were all free, and the only one I was really interested in is the Falstaff Brewery opener, which is second from the top.