Chocolate, chewing gum and rodenticide, says a vet.
The poison to be found most often at the Scottish Terrier and Dog News world headquarters is chocolate. When all these reports about chocolate being toxic for dogs started coming out, I was reminded of a dog we had when I was a kid who demolished all the Halloween candy just before trick or treating began. Even though she also consumed several wrappers, she never seemed the worse for wear. According to this vet, it may have been the low-quality of the chocolate that saved her.
I always knew Coffee Crisp, Aero and Smarties were good for something!