Around 1989, the ASPCA began noticing a trend among dogs who had consumed grapes or raisins…acute renal failure which most often resulted in death. Research has shown, it doesn't matter what brand raisins, whether grapes ingested were store bought or home grown, the results are the same, and dogs for some unknown reason cannot tolerate ingestion of grapes or raisins even in very small amounts.
note-chocolate, cocoa, onions and macadamia nuts can also prove deadly to your dog. For more info visit this link.
Thanks so much Jenni, for bringing this to our attention.