

One thing that’s probably worth noting is that duckweed appears to be a hyperaccumulator species for a bunch of heavy metals - that actually makes it additionally useful for phytoremediation, just watch where you’re getting it from and what inputs it’s receiving if you’re growing it for food.
https://www.sciencedirect.com/science/article/abs/pii/S0048969722030066
At least in the US, vitamins aren’t really regulated, so presumably nothing. Maybe it just hasn’t hit buzzword popularity yet?