 Tobacco smoke is associated with an increased risk of developing respiratory conditions such as bronchitis, pneumonia, and asthma.Tobacco smoke aerosols generated at temperatures below 400 ℃ did not test positive in the Ames assay.In spite of all changes in cigarette design and manufacturing over the last 50 years, the use of filters and "light" cigarettes has neither decreased the nicotine intake per cigarette, nor has it lowered the incidence of lung cancers (NCI, 2001; IARC 83, 2004; U.S.