Actually this is an old myth, like strychnine in LSD blotter, or cyanide in other magic plants. Most companies actually don't 'poison' their seeds. I have read some companies apply a fungicide to their seeds (and it can be seen as a purplish powdery coating) but I've never run across this myself and trust me...I've done a lot of morning glory seeds. If a company does choose to add a fungicide to the seeds, they say so on the label. Seed companies are happy to make sales and so long as the laws are what they are, I don't really think they care who buys their seeds and whether they plan to plant them or eat them....they have no motivation to poison their customers.