Did Shredder know what the mutagen was?

[neatoman]

The reason stated for dumping the mutagen into Yoshi's lair was to "destroy" him. This makes me wonder if he even knew what it was, here are the following possibilities:

1. He knew what it was and hoped for the best scenario
2. He had mistaken it for some kind of poison
3. He had no idea what it was and just wanted to see what would happen

In the first one he's just stupid, he would have known full well Yoshi could turn into something dangerous and did it anyway. In the second one he's not necessarily stupid but certainly incompetent. In the third he should have done some labratory experiments first. None of these answers are really satisfying because they all rely on Shredder being clueless about his own murder weapon to some extent.