Beagle dogs used for smoking tests at Dog Toxicity Unit, Alderley News Photo Getty Images A Review of Toxicity Mechanism Studies of Electronic Cigarettes on Respiratory System One of our customers has had first hand experience of this recently. One cigarette butt can contain enough nicotine to poison a dog. Especially puppies and smaller breeds. What can happen Marijuana Toxicosis in Pets Cummings School of Veterinary Medicine