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Smoking tobacco has adverse effects on many aspects of health, including the likelihood of an individual developing cancer. Cigarettes contain more than 70 known carcinogens1, including known poisons such as arsenic and formaldehyde. Smoking is the greatest risk factor for developing lung cancer, and is related to 85% of all lung cancer cases2.

Smoking can also increase the risk of developing the following types of cancers: bladder, cervix, colon and rectum, esophagus, kidney, larynx, mouth and throat, pancreas, stomach, nasal cavity, liver, acute myelogenous leukemia and some types of ovarian tumours3.

According to the Canadian Tobacco, Alcohol and Drugs Survey, 15% of Canadians smoke, with men smoking more than women4. This is the lowest smoking rate ever recorded in Canada. This decrease in smoking rates is largely attributed to prevention efforts and has contributed to an overall decrease in the incidence of lung cancer in Canadian males since the mid-1980s and a plateau of lung cancer in females since 20065.

Second-hand smoke

It is not just the person that smokes that is at risk, but also those around them. Second hand smoke is a dangerous risk factor for cancer. Second hand smoke is the smoke that a smoker breathes out as well as the smoke that the burning cigarette emits. Approximately 800 Canadians who don’t smoke die from second-hand smoke every year6.

Second-hand smoke also adversely affects children and babies. If a woman is pregnant and smokes, they are passing smoke through the blood, affecting fetal development. This woman is then more likely to miscarry, deliver early and have problems during delivery. After birth, these babies exposed to second-hand smoke prenatally are more likely to get sick from other children and die from SIDS (sudden infant death syndrome). Children who are exposed to second-hand smoke are more likely to suffer from coughing, wheezing, ear infections, asthma, bronchitis, croup and pneumonia.

Smokeless Tobacco and Cancer

While it may seem as though eliminating smoke should eliminate cancer risk, this is not the case. Smokeless tobacco includes chewing tobacco and snuff; it is a type of tobacco that is not burned, but instead absorbed through the mouth lining. It contains at least 28 carcinogens and is known to cause oral, esophageal and pancreatic cancers7.

Hookah (waterpipe) Smoking

A hookah, or waterpipe, is an instrument used for smoking vapourized tobacco. Smoking a hookah has its roots in Persia, and is a cultural practice in many areas globally including the Middle East, South Asia and Africa. There has been a recent surge in the popularity of these waterpipes in North America, however, limited data makes the exact number of people who smoke waterpipes difficult to determine. In Canada in 2012/2013, 14.3% of high school students report ever using hookah. This was a significantly larger percentage than those having reported use in 2010/20118.

While detailed studies about the harms of hookah smoking are limited, preliminary findings suggest much the same health impacts as cigarette smoking. This includes increased risk of lung cancer, respiratory illness and low birth weight9.

What’s particularly concerning is that youth perceive using hookah as less dangerous than cigarettes, potentially contributing to its increase popularity in this demographic10. More research and public education on the dangers of waterpipes is needed to reverse this trend.


E-cigarettes are a new method for using tobacco. They work by delivering vaporized nicotine, contained in a special cartridge, into the lungs. The nicotine inside e-cigarettes is the same as in cigarettes; therefore, the addictive potential is much the same. There is a strong debate among health professionals regarding the proper use of e-cigarettes. Currently, it is thought that e-cigarettes are safer than smoking cigarettes, but they still contain nicotine, and may pose other dangers to health that are not currently known. It is not determined if they should be marketed as a smoking cessation device. It is also possible that e-cigarettes could act as a ‘gateway drug’ leading non-smokers to use tobacco. A recent study by the Canadian Cancer Society showed that, in Quebec, 34% of students in secondary school had already reported past e-cigarette use. It also showed that 8.5% of grade 6 students had tried e-cigarettes11. Therefore it is a concern that e-cigarettes are particularly popular among youth and will potentially provide a bridge to smoking cigarettes. It is also a concern that e-cigarettes could make smoking popular again, effectively undoing the public health measures which have successfully made smoking an undesirable and unappealing practice.

A recent study also suggest that ninth graders in Los Angeles that used e-cigarettes were about 2.5 times more likely to smoke cigarettes, hookahs or cigars than their peers. This is one of the first studies to address the public health concern that e-cigarettes could act as a gateway to cigarette smoking. For more information, the journal article can be found here, and the wall street journal news piece can be found here.

Because e-cigarettes have not been on the market for very long, not much is known about the health risks, including the risk of developing cancer. Some carcinogens have been found in certain e-cigarettes including a toxic chemical found in antifreeze. However, the chemicals may vary based on the brand of e-cigarette cartridge. Regardless, people who want to quit smoking due to the health risks should first turn to an FDA approved method instead of e-cigarettes.


1. Health Canada (2011) Carcinogens in Tobacco Smoke. Retrieved July 2015 from

2. Canadian Cancer Society (2015) Tobacco. Retrieved July 2015 from

3. Canadian Cancer Society (2015) Smoking and Cancer. Retrieved August 2015 from

4. Health Canada (2013) Canadian Tobacco, Alcohol and Drugs Survey. Retrieved August 2015 from

5. Canadian Cancer Society’s Advisory Committee on Cancer Statistics. Canadian Cancer Statistics 2015. Toronto, ON: Canadian Cancer Society; 2015

6. Canadian Cancer Society (2015) Second-hand smoke is dangerous. Retrieved August 2015 from

7. International Agency for Research on Cancer. Smokeless Tobacco and Some Tobacco-Specific N-Nitrosamines. Lyon, France: World Health Organization International Agency for Research on Cancer; 2007. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans Volume 89.

8. Minaker, L.M., Shuh, A., Burkhalter, R.J., Manske, S.R. (2015) Hookah use prevalence, predictors and perceptions among Canadian youth: findings from the 2012/2013 Youth Smoking Survey. Cancer Causes and Control 26: 831-838.

9. Akl, E.A., Gaddam, S., Gunukula, S.K., Honeine, R., Abou Jaoude, P., and Irani, J. (2010) The effects of waterpipe tobacco smoking on health outcomes: a systematic review.

10. Hammal, F., Wild, T.C., Nykiforuk, C., Abdullahi, K., Mussie, D., and Finegan, B.A. (2015) Waterpipe (Hookah) smoking among youth and women in Canada is new, not traditional. Nicotine and Tobacco Research 10: 10.1093/ntr/ntv152.

11. Canadian Cancer Society (2014). The Canadian Cancer Society’s exclusive study: 5,000 children have already tried an electronic cigarette in Grade 6! One in three high school students have already smoked it (142,000 youths). Retrieved August 2015 from