Have you seen the warnings on glacial acetic acid, and how it has to be shipped? And the stuff is actually purified and concentrated white vinegar. Dilute it and use on a salad.

As for toxicity, don't worry about it. Just don't dump it directly into a fish bowl or something like that. It actually takes a lot of photochemicals to mess up a septic tank, and normal municipal sewage systems handle waste that's far nastier and concentrated than hobbyist photochemicals.