Opening with a discourse on poisons in RPGs - the balance between being too deadly and just plain not scary enough, and their use as a plot device rather than as a combat option - this neat little product provides no less than EIGHT ingenious and well-thought out poisons to weave into your plots.
Unless you have peculiarly horrible characters, the best use for these is as something to investigate - perhaps as hirelings or when a friendly NPC succumbs to one. Evil characters, of course, may set out to use them. These are not, however, the sort of poisons you merely smear on your weapons or dust over someone's dinner as if they were some exotic condiment.
Each one comes with a bit of fiction demonstrating its use and descriptive text giving an overview. Then comes notes on creating the poison, detecting it and (should such detection fail) treating the victim. These are followed by plot hooks, any one of which could develop into a whole adventure...
Should a culture in your game world be particularly enamored of using poison, one or more of the adventure seeds could be used to point the way there, maybe sparking off a whole campaign. Or a single plot hook may provide but an interesting side-adventure in a campaign with a completely different focus.