There are new dangers associated with secondhand smoke. Researchers say it increases a woman's risk of getting breast cancer.
The study was conducted by the Air Resources Board in California.
It found that women exposed to secondhand smoke have up to a 90–percent greater risk of breast cancer.
The Director of the Center for Tobacco Research, Dr. Michael Fiore, ays this will only increase the pressure for more communities to ban smoking in all workplaces. "I think this is going to be a powerful motivator to think about creating more smoke free ordinances at the local level and even at the statewide level here in Wisconsin."
Forty-thousand women die from breast cancer every year. The study did not estimate how many of those deaths were caused by exposure to secondhand smoke.