Hello. I was wondering if you knew whether or not iron filings were poisonous for dogs. My dag ate through an air-activated heating pad which contained 2 grams of iron filings. I know that iron is poisonous though I have not been able to find anything about iron filings. He has done this once before and when I took him to the vet they said that they were unable to find out anything as well. He seems fine at the moment, but I just thought that I would check.