Dogs are in danger, too, of ETS-related cancers. In 1992 a study done at Colorado State University found that dogs exposed to secondhand smoke in the home was 1.6 times more likely to develop lung cancer than dogs not exposed. Factors such as how many smokers lived in the home, how many packs a day they smoked, the time spent inside the home by the dog and the dog’s age, body weight and skull shape were all taken into consideration.

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