Secondhand smoke can be dangerous to your cat by causing respiratory issues and even cancer. Since your cat is in your home at all times she cannot escape the smoky air all day and all night long. All the household surfaces such as the sofa, drapes, carpeting and even her bed are covered with smoke residue so your cat experiences contact exposure everywhere she goes. And she ingests the smoke residue whenever she grooms herself. The best and healthiest solution is to forbid smoking in your home. Otherwise, open the windows to air out the home often. Wash all cloth items frequently in hot water especially the items your cat spends her time sitting on. Brush your cat and clean her with wipes to remove some of the smoke residue. Empty ashtrays promptly since your cat could get sick from chewing on cigarette butts. For more information, contact your Colorado Springs, CO veterinarian.