^Not all varieties possess the same properties or active ingredients.
I'm not all that surprised to hear the product is being considered for scheduling. Different varieties contain different active ingredients and some (e.g. Caerulea, Lobatael etc) contain cyanogenic glycosides which can be hydrolysed (by beta-glucosidase also present in the plant) in the acid environment of the stomach to produce hydrogen cyanide. Mind you, apple, peach and apricot seeds also contain amygdalin (B17) which will do the same thing, although it's not typical to eat these seeds (you'd need lots of apple seeds and have to chew them. You wouldn't need many apricot seeds however. They are banned in Australia for this reason).[Edit: mmm...they are actually being sold online these days, so perhaps the law has changed in this regard. Apricot seeds are often taken as a natural cure for cancer; p_d]
Passionflower is perhaps better known for MAOi properties although from reports, these would seem to be weak at best with most varieties. It's possible though, that interactions with prescribed medications could occur and this along with the potential toxicity of some varieties may be the reason why banning some varieties is being considered.
Many of the over 500 varieties of passiflora are neither toxic nor contain psychoactive compounds. We have the foetida growing wild in this area along the coastal tracks. It's a weird looking plant; the fruit uninviting and tiny, although they taste quite good.