Tobacco Active and Passive Smoking

8. Conclusions on tobacco and cancer

• 8.1 Conclusions on active smoking
• 8.2 Conclusions on passive smoking

8.1 Conclusions on active smoking

There is sufficient evidence in humans that tobacco smoking causes cancer at many sites, i.e. lung, mouth, pharynx, nose and paranasal sinuses, larynx, oesophagus, stomach, pancreas, liver, urinary tract (bladder, ureter and kidneys), cervix (neck of the uterus) and bone marrow (myeloid leukemia). There is evidence suggesting that tobacco smoking does not cause breast cancer or cancer of the uterus lining in women.

There is sufficient evidence in test animals that tobacco smoke and tobacco smoke condensates are carcinogenic.

Therefore, the International Agency for Research on Cancer (IARC) has classified tobacco smoking and tobacco smoke as “carcinogenic to humans” (Group 1). More...

8.2 Conclusions on passive smoking

There is sufficient evidence in humans that passive smoking causes lung cancer.

In test animals, there is limited evidence that mixtures of mainstream and sidestream tobacco smoke are carcinogenic but there is sufficient evidence that sidestream smoke condensates are carcinogenic.

In addition, possible carcinogenic effects of secondhand smoke in household pet dogs were noted.

Therefore, the International Agency for Research on Cancer (IARC) has also classified passive smoking as "carcinogenic to humans" (Group 1). More...