Balsamic Vinegar... contains lead?

Is this normal?  In reading my vinegar labels looking for sodium I saw this little box that I obviously didn't notice when I bought it.  My husband and I had used half the bottle.  Kind of scary!  Kind of scary that I didn't see it.  It's not like they were trying to slip it by me.  I just never would have thought in checking the nutrition of my food I needed to look for lead.

Why does my tongue feel like I've been eating paint chips?