The Cancer Blog is on it:According to new research 20 percent of women and 8 percent of men with lung cancer have never smoked. So how did they get sick? Secondhand smoke that’s how,
It's not yet clear why women are more likely to develop the disease. Perhaps they are more susceptible to all forms of smoking -- whether direct or secondhand -- or maybe because more men smoke than women, women are more likely to be exposed to secondhand smoke.
While smoking is the leading cause of lung cancer, there are other factors to blame for disease incidence. Radon, asbestos, chromium, and arsenic are all associated with lung cancer.