No, there is something in the skin.
It really depends on the size of the dog, and the amount of grapes he took down. I see your dog is almost one year old. So I'll assume about 70+ lbs. Although grapes could have an ill effect, I believe that your dog would need to consume A LOT of grapes for them to be fatal. You might have a little stomach discomfort, so just watch him.
If by now nothing has happened, you're probably in the clear of any major issues.