Lots of info like this on the web, google botulism toxin pressure cooker, ton-o-stuff.
This was interesting:
We have been told to throw swollen food cans away. However, with Chastisement unfolding; a stock bubble about to burst, earth changes over the horizon, you may want to save those swollen cans, if food becomes scarce, and your food storage gets very thin. Then you can open the swollen cans carefully, and pour into a container, taking care not to splash any on you; bring to a boil for 15 minutes (30–40 minutes would be better) and eat, better to pressure cook for 15 psi for 15 minutes at 250 F. If it contains botulism, the bacteria's toxin, it will be destroyed. High heat destroys the toxin, but not the spores; pressure cooking does destroy the spores using the above psi and temperature. The spores can withstand boiling for nearly 20 hours. Most people are unaware this.
LOL That reminds me of someone here on Freerepublic commenting that if things get really bad we will be giving canned food as Christmas gifts.
Thanks. The next question is, do the spores need to be tricked into opening? What about allowing to cool while covered, then bringing to pressure again?