Carcinogenic Effects of Cigarette Smoke

smoke and cancer

Last Updated on 20 June 2024

It is globally recognized that cigarette smoke has carcinogenic effects. Moreover, nowadays, the incidence of cancer seems to be higher among smokers than non-smokers. The types of cancers affecting smokers are also more deadly, invasive and aggressive.

Why? Maybe modern cigarettes are more harmful than the ones produced in the past century?

Aside from the answers you’ll find in the article, the matter of carcinogenic effects of cigarettes has always passed over in silence, or rather, it has always been believed that the link between tobacco smoke and cancer was only an unlikely event.

Instead, over time, it has been discovered that cigarette smoke can cause not only lung, mouth and throat cancers, but also pancreatic cancer, leukemia, stomach and colon-rectal cancers and even ovarian cancer.

When Was It Discovered that Cigarette Smoke Causes Cancer?

The ties among cigarette smoke and cancer were discovered in 1939, in Germany, during Nazism.

At that time, German scientist Franz Müller conducted an epidemiologic study finding that tobacco smoke was a cause of cancer.

This discovery was confirmed four years later by another study conducted by Eberhard Schairer and Erich Schöniger, who proved that tobacco smoking is linked to the development of lung cancer.

Due to the ethical infringements committed by German scientists during the Second World War; the results of these studies were ignored for a long time.

But, as of the 1950s, the evidence of carcinogenic effects of cigarette smoking started to emerge in other Countries, as well. The first scientist, who submitted to the scientific communities a study showing how the risk of cancer increases with the quantity of smoked tobacco, was British epidemiologist Richard Doll.

Shortly thereafter, two scientists of the American Cancer Society, Cuyler Hammond and Daniel Horn,presented the results of a research proving that smokers have a 52% higher risk of death than non-smokers.

How Carcinogenic is Smoking?

A study published in Science magazine revealed that the consumption of 20 daily cigarettes causes 150 DNA mutations. DNA is the molecule that controls the growth of cells, giving them proper genetical instructions.

carcinogenic effects of smoke

DNA mutations are the main cause of cancer, especially if the immune system is impaired by the harmful effects of the toxic compounds inhaled when you smoke.

The high risk of cancer for smokers is, indeed, closely linked to the carcinogenic substances contained in cigarettes. What are these substances?

There are 7000 different chemicals in tobacco smoke and in the related cigarettes, but only 69 are considered carcinogenic.

Carcinogenic Substances in Cigarette Smoke

According to the International Agency for Research on Cancer, these are some of the human carcinogens found in tobacco smoke:

1.    Formaldehyde

2.    Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene

3.    Arsenic

4.    Nickel

5.    Polonium 210

6.    Beryllium

7.    Chromium VI

8.    Cadmium

9.    Aromatic amines

10.  1 3-Butadiene

11.  Benzene

12.  Vinyl chloride

13.  Ethylene oxide

Cigarette smoke also contains DDT and dioxins. According to a study, these dioxins are similar to the ones found in “flue gas samples collected from a municipal waste incinerator”. DDT, instead, is the residue of the insecticide used during the cultivation of tobacco. This compound has been banished in Europe, because it is considered highly carcinogenic.

However, the tobacco used to produce cigarettes is mainly imported from Countries where agricultural restrictions are not so rigid and where the usage of DDT is still permitted.

The compounds listed above include heavy metals, disinfectants (formaldehyde) radioactive substances (Polonium 210), poisons, pesticides, products of incomplete combustions also found in automotive exhaust, plastic residues and substances used in the aerospace industry and to produce explosives (benzene).

Many of these substances are also involved in ozone depletion and environmental pollution.

The Istituto Tumori in Milan, for example, in 2016, calculated that only five cigarettes pollute air like a locomotive.

All these substances have carcinogenic effects indoors and outdoors. Not only first-hand smoke, but also second and thirdhand smoke have carcinogenic effects and cause DNA mutations, according to a study published on Academic Oxford. (Thirdhand smoke consists of the residues of cigarettes released in the external environment).

Last, but not least, cigarette smoke also contains nicotine. Is this substance carcinogenic? Let’s discover the answer.

Carcinogenic Effects of Nicotine

Nicotine is the psychoactive substance of tobacco, and it is the one which makes smoking addictive. This substance is naturally contained in the leaves of tobacco.

Nicotine is not considered carcinogenic, but since it is capable of modifying the brain, causing smoking addiction, it is the accomplice of the risk to develop cancer from carcinogenic chemicals of smoke.

Furthermore, it has been observed that nicotine reduces the effectiveness of chemotherapy. That is why tumors developed by smokers seem more invasive, aggressive and deadly.

A shocking study published in Nature also revealed that nicotine promotes breast cancer metastases, because it stimulates the growth of the neutrophils that control the enzymes for the progression of cancer!

What Type of Cancer is Caused by Smoking?

Hence, yes, cigarette smoke is highly carcinogenic and can cause 17 different types of cancer in the following areas of the body:

1.    Oral cavity

2.    Nasal cavity

3.    Pharynx

4.    Larynx

5.    Esophagus

6.    Liver

7.    Lung

8.    Pancreas

9.    Ovary

10.  Uterine cervix

11.  Colon-rectus

12.  Stomach

13.  Kidney

14.  Ureter

15.  Bladder

16.  Blood

17.  Breast

As regards breast cancer, the International Agency for Research on Cancer (IARC) has concluded that” there is limited evidence that tobacco smoking increases the risk of breast cancer (by 10–30%), based on consistent evidence from studies in humans”.

Furthermore, European studies always observed that the percentage of pancreatic cancer and myeloid leukemia related to tobacco smoke is equal to 13%, while the percentage of liver and bladder cancers respectively reached 25 and 50%!

While, in the past century, smokers got sick of lung cancer (it is still the leading cancer for those who smoke), our century has been plagued by smokers who experienced the most deadly and severe forms of pancreatic cancer.

We also find celebrities among the victims.

  • Italian tenor Luciano Pavarotti, died from pancreatic cancer in 2007. He was a pipe smoker.
  • American actor Patrick Swayze, died from pancreatic cancer in 2009. He was a cigarette smoker.
  •  Italian journalist Oriana Fallaci, died from pancreatic cancer in 2006. She was a cigarette smoker.

We don’t know if these deaths are merely coincidental, but it is shocking to learn that the victims were all smokers. Cigarette smoke victims are a whole lot more, unfortunately.

I lost some friends of mine for cancer, one for pancreatic cancer, another one for leukemia.

Their cancers were extremely invasive and not curable. Both of them were smokers.

Furthermore, my dad died from colorectal cancer in 2004. He had been a smoker until my adulthood.

My father-in-law died from leukemia in 1980, when my husband was still a child. My father-in-law was a smoker.

Once, an acquaintance of mine said to me: “I will never eat out of season food! I prefer following a healthy diet”. She died from breast cancer a few years ago. She was a smoker.

Coincidences are starting to be too many, by now.

According to the World Health Organization, cigarette smoking is the first avoidable cause of death in our society. Indeed, yearly, cigarette smoke kills 8 million active smokers all over the world, in addition to 1.2 million passive smokers.

There is surely an underlying, twisted mechanism that is causing what anti-smoke activists define as “the massacre of smoke”, a real scourge, who none intends to stop!

Carcinogenic Mechanism of Cigarette Smoke

The carcinogenic effect of cigarette smoke occurs during the combustion of the cigarette, especially from the end.

All the substances we saw above get burned and turned into toxic gases and in a sticky yellow, black- brown substance called Tar.

The latter is the residue of cigarette combustion and contains all the carcinogenic substances of smoke, not only the ones listed in this article, but even all the 69 carcinogenic chemicals that typically a common cigarette has.

Tar deposits on teeth and lungs, and paralyzes the cilia that sweep away the smoke from your respiratory system.

Simultaneously, smoke becomes the vector of these carcinogenic chemicals, which spread in blood, stomach, kidneys, liver, pancreas and over, while carbon monoxide generated from the entire combustion of the cigarette reaches your bloodstream and ties with the hemoglobin.

When this happens, oxygen cannot bind with the receptors of blood cells, which, in turn, suffer a severe change in their functions of growth and division.

But the carcinogenic chemicals of cigarettes put cells into a severe oxidative stress, which is the primary cause of DNA mutation and cancer.

Just think that as regards smoking related pancreatic cancer, a study published in 2018 on Gastroenterology, the most prominent journal in the field of gastrointestinal disease, revealed that the cells of aggressive pancreatic cancer have the features of stem cells!

The carcinogenic mechanism of cigarette smoke has always been the same, but it seems that the effects on human cells are more harmful than in the past.

There is, in fact, a shocking truth regarding smoke addiction and carcinogenic effects of smoking. We’ll explore it in the paragraph below.

Carcinogenic Effects in Modern Cigarettes

The shocking truth is that modern cigarettes contain more additives and are processed and manipulated to give more nicotine addiction.

Cigarette manufacturers, in fact, made cigarettes more addictive and, hence, more carcinogenic, because the more you smoke, the higher the cancer risk is.

This shocking truth has been revealed in an Australian research paper titled: “Keep a low profile”: pesticide residue, additives, and freon use in Australian tobacco manufacturing”.

modern cigarettes

Indeed, to make smoking more pleasurable and reduce the harshness of smoking for the newbies, manufacturers add sugar and other substances that improve the taste of the cigarette.

During the combustion, the burnt sugar becomes carcinogenic, as well. While they burn, All the substances of cigarettes produce, in turn, carcinogenic chemicals.

Just think that smoking is also causing a rise of diabetes in India. Are modern cigarettes processed with sugar responsible for this epidemic? Maybe. But now, doctors are absolutely sure that smoking is an independent risk factor for many diseases, including cancer and diabetes.

It also seems that smoking increases the adsorption of asbestos, confirming a close correlation between cigarette smoke and mesothelioma.

Light cigarettes have the same carcinogenic effects of common cigarettes. They are thus defined, because they should contain less nicotine and less Tar. But, as confirmed by the National Cancer Institute, light cigarettes expose smokers to the same carcinogenic chemicals of regular cigarettes.

Remember that the carcinogenic effect is not in the type of cigarette you have, but in the smoke generated from the combustion of the paper.

This explanation could push you to ask if cigar smoke is safer than cigarette smoke. Unfortunately, the answer is No.

Even though a cigar is made with no paper and with tobacco leaves which wrap it, it contains more cancer related chemicals, such as the dangerous nitrosamines.

The latter are the most carcinogenic chemicals naturally contained in tobacco. Nitrosamines are regularly inhaled both with cigars and cigarettes.

The cancer risk of cigar smoke has always been confirmed by the National Cancer Institute.

The above-mentioned risks are pushing many smokers to switch to electronic cigarettes.

Carcinogenic Effects of E-cigarettes

There aren’t many studies about any carcinogenic effects of e-cigarettes. These devices represent a new way of smoking used to overcome nicotine addiction.

The carcinogenicity may depend on the type of substances that these cigarettes contain.

They lack the combustion process that triggers the inhalation of the toxic chemicals of regular cigarettes.

The inhalation of nicotine occurs through vapor, in this case.

E-cigarettes, indeed, are a device containing a liquid mixture of water, flavors, aromatic substances and liquid nicotine.

There are also devices that contain heated tobacco. These are e-cigarettes containing leaves of tobacco that get heated instead of getting burned.

Manufacturers, obviously, say that cigarettes with heated tobacco have null carcinogenic effects. But, according to the scientific community, the cancer risk is equal to regular cigarettes, because tobacco contains naturally carcinogenic substances, such as the aforementioned nitrosamines.

When the mixture gets heated, the device emits vapor which gets slowly inhaled with all the beneficial or harmful substances it contains. For this reason, e-cigarettes are called vaporizers, as well.

To quit smoking, the dose of nicotine and tobacco of e-cigarettes should be diminished day by day and replaced with healthier substances, such as essential oils and organic flavors.

Chemical flavors and formaldehyde could be carcinogenic chemicals contained in e-cigarettes, but, currently, we don’t know exactly what chemicals are in an e-cigarette because most harmful or potentially harmful substances contained in e-cigarettes are not listed or not properly labeled.

By contrast, a vaporizer containing only essential oils can be a relaxing solution to forget nicotine addiction and avoid the carcinogenic effects of tobacco.

Explore Further by Reading This Book


There is no doubt: cigarette smoke, cigars, pipe, and light cigarettes have carcinogenic effects. The marketing of smoking should be forbidden, but, unfortunately, none has had the courage to do it, so far.

E-cigarettes, instead, should be a temporary solution to quit smoking permanently.

Moreover, without smoke, you’ll help keep the environment and your body healthy and cleansed.

The news you found in this article are all fact checked and supported by international health sources and by my personal experience with the ones I lost for the fault of cigarette smoke.

If the shocking news of this article helped you quit smoking, let me know. I’ll be happy to hear that authentic information has healthy effects, sometimes.

References and Bibliography

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  2. Ludmil B. Alexandrov Young Seok JuKerstin Haase Peter Van LooIñigo Martincorena Serena Nik-ZainalYasushi TotokiAkihiro FujimotoHidewaki NakagawaTatsuhiro ShibataPeter J. Campbell Paolo Vineis David H. Phillipsand Michael R. Stratton – Science – Mutational signatures associated with tobacco smoking in human cancer – November, 4, 2016 – Vol 354, Issue 6312 • pp. 618-622 -DOI: 10.1126/science.aag0299
  3. International Agency for Research on Cancer – Table 2: Some of the human carcinogens found in tobacco smoke
  4. Muto H, Takizawa Y. Dioxins in cigarette smoke. Arch Environ Health. 1989 May-Jun;44(3):171-4. doi: 10.1080/00039896.1989.9935882. PMID: 2751353
  5. Chapman S “Keep a low profile”: pesticide residue, additives, and freon use in Australian tobacco manufacturing Tobacco Control 2003;12:iii45-iii53
  6. Dr. Livia Vanessa Siracusano – Nicotina: quali sono gli effetti sul nostro organismo – Humanitas – February 19, 2021
  7. Tyagi, A., Sharma, S., Wu, K. et al. Nicotine promotes breast cancer metastasis by stimulating N2 neutrophils and generating pre-metastatic niche in lung. Nat Commun 12, 474 (2021).
  8. Istituto Tumori Milan – Cinque sigarette inquinano quanto una locomotiva: tutti i danni del fumo passivo – May, 31, 2016
  9. Bo Hang, Altaf H. Sarker, Christopher Havel, Saikat Saha, Tapas K. Hazra, Suzaynn Schick, Peyton Jacob, III, Virender K. Rehan, Ahmed Chenna, Divya Sharan, Mohamad Sleiman, Hugo Destaillats, Lara A. Gundel, Thirdhand smoke causes DNA damage in human cells, Mutagenesis, Volume 28, Issue 4, July 2013, Pages 381–391,
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  11. AIRC – Fumo: le domande più frequenti, Reviewed May 21, 2020
  12.  Fabrizio Federici – La Strage del Fumo… ConsultPress.Eu – November 17, 2020
  13. Rama Krishna Nimmakayala, Parthasarathy Seshacharyulu, Imayavaramban Lakshmanan, Satyanarayana Rachagani, Seema Chugh, Saswati Karmakar, Sanchita Rauth, Raghupathy Vengoji, Pranita Atri, Geoffrey A. Talmon, Subodh M. Lele, Lynette M. Smith, Ishwor Thapa, Dhundy Bastola, Michel M. Ouellette, Surinder K. Batra, Moorthy P. Ponnusamy, Cigarette Smoke Induces Stem Cell Features of Pancreatic Cancer Cells via PAF1,Gastroenterology,Volume 155, Issue 3,2018,Pages 892-908.e6,ISSN 0016-5085,
  14. Dr. N. Selvaraj – Diabetes and smoking – TimesofIndia – August 19, 207
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Author: Rosalba Mancuso
Rosalba Mancuso is a medical journalist, an international content writer credited at the University of Washington and a blogger born in Sicily. She is internationally appreciated for founding a network of four websites in English. On, Rosalba writes well researched and detailed health articles backed by her experience as a medical writer for pharma companies and as a PR assistant for a clinical analysis laboratory. She is also a member of the AHCJ, American Association of Health Care Journalists and Center for Excellence in Health Journalism. Her health magazine survives thanks to spontaneous donations, and sponsorships with brands and clinical organizations.