parazapper
Hi Cora,
The seller probably does not know any more than you do about what they are selling.
When I was a chemist many years back, we used EDTA as a titrating agent to help determine metal content such as Magnesium. One thing that we were constantly warned about was that DiSodium EDTA was considered to be a neurotoxin.
Funny how things change as it is frequently used as a chelation agent today.