A carcinogen is any substance or agent capable of causing cancer. There are many examples of carcinogens, including cigarette smoke, UV rays, processed meat, and more.
The International Agency for Research on Cancer (IARC) and the
This article looks at known and probable carcinogens, including their types and examples. It also explores how to reduce the risk of exposure and more.
A carcinogen is
Some carcinogens, such as UV rays from sunlight, occur naturally. Others originate from artificial sources, such as cigarette smoke.
Most carcinogens cause cancer by producing mutations in a cell’s DNA. Different carcinogens can cause different types of cancer.
Researchers divide carcinogens into three main categories. These include:
- Chemical carcinogens: These are carcinogens that people release into the environment through pollution, such as
throughcar exhaust fumes, industrial by-products, and cigarette smoke.
- Physical or environmental carcinogens: These carcinogens come from the environment. UV rays from sunlight and radiation from X-rays or other radioactive materials are examples of physical carcinogens.
- Oncogenic viruses: These are viruses that can cause cancer.
Examplesinclude human papillomavirus (HPV), Epstein-Barr, and hepatitis B.
This section looks at common examples of carcinogens that the IARC and the
Both the IARC and NTP classify alcoholic beverages as known carcinogens. According to the IARC, alcoholic beverages can cause multiple cancers, including oral cancer, colon cancer, liver cancer, and more.
Asbestos is known by the IARC to cause mesothelioma, a type of aggressive cancer, and stomach, colon, lung, and ovarian cancers. The NTP also classifies asbestos as a known carcinogen.
According to the NTP, diesel exhaust particulates are known carcinogens. The IARC states that engine exhaust fumes may cause bladder cancer, but there is inconclusive evidence for this in humans.
Formaldehyde can cause multiple different types of leukemia, according to the IARC.
Consuming processed meat is known to increase the risk of cancers of the rectum and colon, according to the IARC. It may also cause stomach cancer.
Processed meats are any meat products manufacturers preserve by smoking, curing, or adding chemical preservatives.
Examples of processed meats include:
- deli meats
- beef jerky
- canned meats
Radon is a radioactive gas that occurs naturally in the environment. Both the IARC and NTP classify radon as a known human carcinogen.
The IARC and the NTP classify all tobacco products as carcinogens.
Tobacco smoke and tobacco products can cause many types of cancer, including:
UV rays from tanning devices and welding can cause skin cancer and eye cancer. Solar radiation from the sun can also cause melanoma.
The NTP’s 15th Report on Carcinogens lists
The following examples may be present in either the IARC, the
Some examples of carcinogens include:
- coal dust and emissions
- Epstein-Barr virus
- estrogen-progestogen combined oral contraceptives
- estrogen therapy for menopause
- hepatitis B
- hepatitis C
- HIV type 1
- mineral oils
- outdoor air pollution
- red meat consumption
- X-rays and gamma rays
Many people regularly come into contact with carcinogens due to their occupation.
Some occupations can expose a person to more carcinogens than usual. These include firefighters, painters, and people working in industrial and manufacturing settings.
Carcinogen exposure in the workplace can be more harmful than everyday exposure. This is because a person who works with carcinogens may come into contact with them more regularly, which may increase their risk of developing cancer.
The Agency for Toxic Substance and Disease Registry associates the following cancers with various workplace carcinogens.
|Cancer||Substances, occupations, or processes|
|bladder||• aluminum production|
• rubber industry
• leather industry
• mustard gas
• isopropyl alcohol
• vinyl chloride
• coal fumes
• foundry substances
• nickel refining
• coke oven fumes
• nickel refining
• soot, tars, and oils
|• ethylene oxide|
|nasal cavity and|
|• isopropyl alcohol|
• mustard gas
• nickel refining
• wood dust
• leather dust
• mustard gas
• coal tars
• mineral oils
|soft-tissue sarcoma||• chlorophenols|
In the United States, workplaces must follow legal regulations to reduce their employees’ exposure to known carcinogens. They may take safety measures such as supplying protective gear and monitoring a person’s exposure.
People can also take steps to limit their exposure to carcinogens outside of the workplace. These
- quitting smoking, if applicable
- wearing sunscreen and limiting sun exposure
- avoiding processed meats
- avoiding alcohol
- receiving HPV and hepatitis B vaccinations when appropriate
This section answers some frequently asked questions about carcinogens.
What are the three groups of carcinogens?
The IARC break down carcinogens into groups 1–3, depending on their risk levels.
|Group||Group description||Number of agents|
known to cause cancer in humans
probably causes cancer in humans
|2B||possibly causes cancer in humans|
researchers are unable to classify its carcinogenicity in humans
Is nicotine a carcinogen?
Neither the IARC nor the
However, they both list N-Nitrosonornicotine (NNN), a nicotine derivative, as a known carcinogen. NNN is present in a variety of tobacco products.
Do cell phones cause cancer?
Because cell phones emit radiation, many people worry that using them can cause cancer.
However, according to the
Can the body get rid of carcinogens?Anonymous
Our bodies have a natural detoxification system that helps different tissues detoxify in a number of ways. These systems include the lungs, skin, digestive system, liver, and kidneys. Ways that we can help boost our body’s natural detoxing process include avoiding dietary carcinogens, avoiding sun damage, and staying active.Jenneh Rishe BSN, RN Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.
A carcinogen is any substance or agent that has the potential to cause cancer. Common carcinogens include alcohol, tobacco, processed meats, UV rays, radon, and asbestos.
Some people may come into contact with carcinogens in their workplaces. However, employers in the U.S. must take steps to protect employees from carcinogen exposure.
A person can also reduce their exposure to carcinogens in everyday life. Quitting smoking, avoiding alcohol, and following a balanced, nutritious diet can all help prevent carcinogen exposure and lower the risk of cancer.