I keep having slightly psychedelic responses to eating parsnips. Metallic taste in the mouth, slight skin numbness, and lessening of sensation in my limbs as well a sort of disassociated feeling in my mind. Honestly, the first time it happened it scared me a little, and I was anxious that I could pass something bad onto my child via breastmilk later that day. If it only happened once I would've just chocked it up to a random weird thing, but it has happened 3 times now. I know you are thinking "then just don't eat them", but I really dig the flavor, and would like to eat them as long as I'm not endangering myself or my son.
I know a common reminder in foraging guides is stay away from white carrots because unless you really know what you are doing you could accidentally eat some deadly hemlock. Is it possible that parsnips could possibly interbreed or be distant cousins with a far lesser amount of the hemlock badness? This has also only been happening since I started getting them from my CSA, which often provides us with exotic varieties of produce, it didn't happen when I used to get them from the grocery store.
