Elderberry, Black Elder, European Elder, Bourtree 'Madonna'

Purchased this at the Merritt College plant sale in 2013. Plant is very attractive, with vivid yellow/green variegated leaves. It's doin...Read Moreg well in partial shade, but note that it's quite a slow grower.

My wife is from Hungary. She is very excited that we found an Elder bush here in Illinois. She is always talking about all of the thing...Read Mores she can make with the bloom. She has many recipes. My only concern is that we picked many blooms today from an Elder bush that had green and yellow leaves in Illinois. In Hungary the leaves are green. We just learned that some Elders can be poisonous. My question is, Can the bloom be poisonous or is the berry poisonous?