I wanted to know if anybody had an issue using pavers as a border for a raised, organic veggie garden? In other words, do you think there is a risk of any kind of toxic contaminations?
thanks!

I have never heard of any toxic treatment or sealant on the stones. I would think they're fine.

my concern is structural...if you use small pavers (i.e. brick size) a single width stacked even 3 high (8") can be pushed out by the weight of the soil

you might want to look at "stack-stone" instead of pave-stone, which is usually the size/weight of a heavy concrete block....this is much more likely to withstand the horizontal forces of wet soil...these stones are designed to be used as retaining walls, and can go 16-24" and higher, if need be....(a cheaper solution could be concrete block if appearance is less important, and would limit block to 16" high)

my own square foot gardens (4'x4') raised beds are made of 2x12s, i just let the plants fall over the edge to hide the face of the planter.