Taxol: deadly and a lifesaver?

As described on the Interactions page, the English yew serves as a host for a mutualistic fungus that produces a toxin in almost every part throughout the plant.  This toxin, called taxol, is a very lethal drug if consumed by humans or other animals

For every kilogram of weight of the following mammals, the corresponding weight of yew leaves is fatal:

horse 2 grams
mule 1 gram
sheep 10 grams
goat 12 grams
cow 10 grams
pig 3 grams
dog 8 grams
rabbit 20 grams

So if I were similar to a mule and 1 gram of yew per kilogram of my weight were require to kill me, then at 155 pounds it would only take a little over 4 ounces of yew leaves to do so. Deaths to humans by yew poisoning are not common, but there are some cases in which people have committed suicide by ingesting yew leaves.

Chemical structure of taxol:

Taxol works by preventing cell division or mitosis. It is so good at stopping cell division that it is actually used to prevent cells from dividing uncontrollably in cancer patients! So what is conventionally considered lethal actually saves human lives! However, this chemotherapy does not come without a significant cost. Now this tree, which is already suffering from a diminishing habitat, is also being harvested and stripped of its bark for this medicinal purpose.