What Are 4 Carcinogens

1. What Are The 4 Types Of Carcinogens
2. What Are Carcinogens Definition
3. Level 1 Carcinogen
4. What Are 4 Carcinogens Found In Tobacco
5. Group 1 Carcinogens List
6. Group 4 Carcinogen

In the last government report on carcinogens - known as the '11th Report on Carcinogens (RoC)' - 246 substances made it on the list. Of those substances, 58, such as alcoholic beverages, benzene, mustard gas and coal tars, were identified as known human carcinogens, while the other 188 were not as strongly labeled. The International Agency for Research on Cancer (IARC; French: Centre International de Recherche sur le Cancer, CIRC) is an intergovernmental agency forming part of the World Health Organization of the United Nations.Its role is to conduct and coordinate research into the causes of cancer. It also collects and publishes surveillance data regarding the occurrence of cancer worldwide. A number of the carcinogen classifications deal with groups of substances: aniline and homologs, chromates, dintrotoluenes, arsenic and inorganic arsenic compounds, beryllium and beryllium compounds, cadmium compounds, nickel compounds, and crystalline forms of silica.

A carcinogen is a substance that is capable of causing cancer in humans or animals. If a substance is known to promote or aggravate cancer, but not necessarily cause cancer, it may also be called a carcinogen. Protecting yourself from these known carcinogens is the best way to reduce your cancer risk. But it doesn't hurt to be careful when it comes to other potential dangers, Bevers says. Cell phones do emit a form of radiation. But Bevers says the type your.

Three main lists of internationally recognized carcinogens exist: those of IARC¹ , of the ACGIH² and of the European Union (CLP³). It becomes thus difficult to find one's way as a novice!

In particular when there are disparities as regards their classification as well as the list of chemicals concerned. The different classifications and their definitions are grouped below, so as to bring more light and better understanding regarding these differences.

IARC Classification

The International Agency for Research on Cancer (IARC or CIRC in French) distinguishes four main groups or physical factors on the basis of existing scientific data to assess their carcinogenic potential.

GROUP 1: the agent may be a carcinogenic mixture for humans (proven carcinogen or certainly carcinogenic). The exposure circumstance entails exposures that are carcinogenic to humans. This category is only used when sufficient indications of carcinogenicity for humans are available. Beginning of August 2012, 108 agents are classified in Group 1 of IARC. This group is divided in sub-groups: agents and groups of agents, complex mixtures, occupational exposures and others.

GROUP 2A: The mentioned agents are probably carcinogenic for human beings. The classification of an agent in this category is recommended if there is no formal evidence of carcinogenicity in humans, but corroborating indicators of its carcinogenicity for humans and sufficient evidence of carcinogenicity in experimental animals. Beginning of August 2012, 64 agents and group of agents are included in this list.

GROUP 2B: 272 agents appear on this list of agents probably carcinogenic to humans. There is limited evidence of carcinogenicity in humans and evidence for animals, or insufficient evidence for human beings but sufficient evidence of carcinogenicity in experimental animals (possible carcinogens).

GROUP 3: 508 agents appear on this list and are not classifiable as to their carcinogenicity to humans. (Insufficient evidence for human beings and insufficient or limited for animals).

GROUP 4: to indicate agents which are probably not carcinogenic for human beings. (Evidence suggesting lack of carcinogenicity in humans and in experimental animals). Only one agent is thus classified: Caprolactam.

Classification of the ACGIH

The American Conference of Governmental Industrial Hygienists (ACGIH) distinguishes five categories of chemicals or carcinogenic agents:

• GROUP A1: confirmed human carcinogens (group 1 of IARC and category 1A of the European Union).
• GROUP A2: suspected human carcinogens (group 2A of IARC and category 1B of European Union).
• GROUP A3: confirmed animal carcinogens with unknown relevance to humans (group 2B of IARC and category 2 of the European Union).
• GROUP A4: regroups agents non-classifiable as to their carcinogenicity to humans (group 3 of IARC).
• GROUP A5: regroups agents suspected not to be carcinogenic to humans (group 4 of IARC).
  Classification of the European Union (CLP)
  European Union

Classification of the European Union (CLP)

Category 1A: includes substances whose potential carcinogenicity for humans is known; classification in this category is primarily based on human data.

Category 1B: includes substances whose carcinogenic potential to humans is presumed, classification in this category is primarily based on animal data.

In summary, classification in category 1A and 1B is based on evidential weight of data which may be derived from studies on human beings with a causal link between human exposure to a substance and cancer occurrence (category 1A) and animal experiments for which there is sufficient evidence to demonstrate animal carcinogenicity (presumed human carcinogen) (category 1B)

Category 2: includes substances suspected of being carcinogenic to humans. This classification is done on the basis of evidences obtained from human and/or animal studies not sufficiently convincing to place in category 1A or 1B.

The differences

It may therefore be estimated that chemicals classified in group 1 of IARC, A1 of the ACGIH and in category 1A of the European Union are human categories.

It is important to point out that substantial differences exist, comparing the three lists of carcinogens with each other. Each of these differences cannot be detailed here; we will simply cite the most used substances.

What Are The 4 Types Of Carcinogens

If we take as reference the list of human carcinogens for IARC, we can try to see major differences and similarities that exist with that of ACGIH and of European Union.

Are classified as human carcinogens:

• Asbestos,
• Aminobiphenyl,
• Arsenic and its compounds,
• Benzene,
• Benzidine,
• Chloroethylene,
• Beryllium and its compounds,
• The bis(chloromethyl)ether and the chloromethylether (technical grade),
• Chromium VI and its compounds with the exception of barium chromate classified in group 1B in the European Union,
• Coal tar,
• Methylenebis(2-chloroaniline) (it is worth mentioning that it is classified as probable carcinogen A2 of the ACGIH),
• Naphtylamine.

Slot freebies caesars casino. As we see, there are particularly major differences between the chemicals included in the list of the ACGIH and those of the IARC and the European Union. The European Union and the IARC lists are closer, but it is important to bear in mind that the chemicals classified in group 1 of the IARC can just as well be listed in categories 1A or 1B of the CLP.

Some examples to remember

Many chemicals are classified as carcinogens only by the IARC :

• Azathiopirine,
• Chlornaphazine,
• Myleran,
• Chlorambucil,
• Semustine,
• Cyclosporine,
• Oral contraceptives,
• Cyclophosphamide,
• Diethylsilbestrol,
• Etoposide combined with cisplastine and bleomycine,
• Yperite,
• Helicobacter pylori infections,
• Radioactive iodine,
• Melphalan,
• Methoxy-8-psoralen,
• MOPP,
• Neutrons,
• N-nitrosonornicotine,
• Estrogen therapy,
• Phosphorous 32 (in the form of phosphate),
• Plutonium 239 and 240,
• Radioelements emitting alpha and beta particles,
• Radium 224,226,228,222,
• X and gamma rays,
• Tamoxifene,
• TCDD,
• Thiotepa,
• Thorium 232
• And many viruses.

We will not mention here lists of mixtures and detailed occupational carcinogen exposures in the IARC list.

Other differences give rise to questions

These classification differences can no doubt be explained by the limits of animal testing and other differences in interpretation of human and experimental data but must question ourselves.
For greater safety and security, it seems logical to consider that the classification the most restrictive must be respected but this requires a clear understanding of the various lists.

These lists are reviewed inPROMETRA and meet the following classification:

• 1001: list of carcinogenous chemicals or suspected by the IARC
• 1020: list of carcinogens or suspected according to the ACGIH
• 1030: list of carcinogens or suspected according to the European Union (CLP)

Centre International de Recherche sur le Cancer
American Conference of Industrial Hygienists
Classification Labelling and Packaging of substances and mixtures, (CE) n°1272/2008

Danielle Henny, Occupational Health Physician

By the end of 2010, an estimated 569,490 Americans will have died from cancer. That's more than 1,500 people every day, and 1 out of every 4 deaths in this country [source: American Cancer Society]. So what is giving cancer such a push?

Well, as it turns out, in addition to cancer being hereditary, external factors are at play. For example, about 171,000 of this year's cancer deaths are believed to be caused by tobacco use [source: American Cancer Society]. How is it that external factors like tobacco use can have such a heavy hand in our cancer rates? It all comes down to carcinogens -- cancer-causing agents, like pollutants in the air, ultraviolet (UV) rays and viruses. How and why do carcinogens give cancer the upper hand?

Advertisement

Advertisement

Carcinogens are typically any external causes of cancer, excluding those without a hereditary link. However, for the purpose of this article, we're referring to the following categories of carcinogens from the World Health Organization (WHO):

• Biological (e.g., types of bacteria)
• Chemical (e.g., chemicals in tobacco smoke and asbestos)
• Physical (e.g., UV radiation)

What Are Carcinogens Definition

[source: World Health Organization]

Exposures to these 'agents of evil' can cause some wacky changes to our cells that lead to cancer. For example, some carcinogens can directly cause genetic mutations that foster abnormal cell growth and tumors. Others don't attack our genes directly, but trick our cells into cell division overdrive. That excess division then leads to potential genetic mutations down the road [source: American Cancer Society].

Does this mean that any exposure to a known carcinogen will cause you to develop cancer? The candid answer is, 'It depends.' For one, our genes are under continual attack by genetic mutations, but our DNA usually does a stellar job of repairing itself. That said, though, that 'repairman' skill isn't equal among all of us. Some of us do a better job of repairing our genes than others, which means that some people are more naturally susceptible to the negative effects of a carcinogen. Furthermore, a carcinogen's link to cancer can depend on:

• Age and gender
• Potency: Some carcinogens require pretty heavy exposure to be dangerous, while others are linked to cancer with just a brief exposure.
• Exposure type: For example, were you exposed to a carcinogen one time or continually over a period of years?

GROUP 1: the agent may be a carcinogenic mixture for humans (proven carcinogen or certainly carcinogenic). The exposure circumstance entails exposures that are carcinogenic to humans. This category is only used when sufficient indications of carcinogenicity for humans are available. Beginning of August 2012, 108 agents are classified in Group 1 of IARC. This group is divided in sub-groups: agents and groups of agents, complex mixtures, occupational exposures and others.

GROUP 2A: The mentioned agents are probably carcinogenic for human beings. The classification of an agent in this category is recommended if there is no formal evidence of carcinogenicity in humans, but corroborating indicators of its carcinogenicity for humans and sufficient evidence of carcinogenicity in experimental animals. Beginning of August 2012, 64 agents and group of agents are included in this list.

GROUP 2B: 272 agents appear on this list of agents probably carcinogenic to humans. There is limited evidence of carcinogenicity in humans and evidence for animals, or insufficient evidence for human beings but sufficient evidence of carcinogenicity in experimental animals (possible carcinogens).

GROUP 3: 508 agents appear on this list and are not classifiable as to their carcinogenicity to humans. (Insufficient evidence for human beings and insufficient or limited for animals).

GROUP 4: to indicate agents which are probably not carcinogenic for human beings. (Evidence suggesting lack of carcinogenicity in humans and in experimental animals). Only one agent is thus classified: Caprolactam.

Classification of the ACGIH

The American Conference of Governmental Industrial Hygienists (ACGIH) distinguishes five categories of chemicals or carcinogenic agents:

• GROUP A1: confirmed human carcinogens (group 1 of IARC and category 1A of the European Union).
• GROUP A2: suspected human carcinogens (group 2A of IARC and category 1B of European Union).
• GROUP A3: confirmed animal carcinogens with unknown relevance to humans (group 2B of IARC and category 2 of the European Union).
• GROUP A4: regroups agents non-classifiable as to their carcinogenicity to humans (group 3 of IARC).
• GROUP A5: regroups agents suspected not to be carcinogenic to humans (group 4 of IARC).
  Classification of the European Union (CLP)
  European Union

Classification of the European Union (CLP)

Category 1A: includes substances whose potential carcinogenicity for humans is known; classification in this category is primarily based on human data.

Category 1B: includes substances whose carcinogenic potential to humans is presumed, classification in this category is primarily based on animal data.

In summary, classification in category 1A and 1B is based on evidential weight of data which may be derived from studies on human beings with a causal link between human exposure to a substance and cancer occurrence (category 1A) and animal experiments for which there is sufficient evidence to demonstrate animal carcinogenicity (presumed human carcinogen) (category 1B)

Category 2: includes substances suspected of being carcinogenic to humans. This classification is done on the basis of evidences obtained from human and/or animal studies not sufficiently convincing to place in category 1A or 1B.

The differences

It may therefore be estimated that chemicals classified in group 1 of IARC, A1 of the ACGIH and in category 1A of the European Union are human categories.

It is important to point out that substantial differences exist, comparing the three lists of carcinogens with each other. Each of these differences cannot be detailed here; we will simply cite the most used substances.

What Are The 4 Types Of Carcinogens

If we take as reference the list of human carcinogens for IARC, we can try to see major differences and similarities that exist with that of ACGIH and of European Union.

Are classified as human carcinogens:

• Asbestos,
• Aminobiphenyl,
• Arsenic and its compounds,
• Benzene,
• Benzidine,
• Chloroethylene,
• Beryllium and its compounds,
• The bis(chloromethyl)ether and the chloromethylether (technical grade),
• Chromium VI and its compounds with the exception of barium chromate classified in group 1B in the European Union,
• Coal tar,
• Methylenebis(2-chloroaniline) (it is worth mentioning that it is classified as probable carcinogen A2 of the ACGIH),
• Naphtylamine.

Slot freebies caesars casino. As we see, there are particularly major differences between the chemicals included in the list of the ACGIH and those of the IARC and the European Union. The European Union and the IARC lists are closer, but it is important to bear in mind that the chemicals classified in group 1 of the IARC can just as well be listed in categories 1A or 1B of the CLP.

Some examples to remember

Many chemicals are classified as carcinogens only by the IARC :

• Azathiopirine,
• Chlornaphazine,
• Myleran,
• Chlorambucil,
• Semustine,
• Cyclosporine,
• Oral contraceptives,
• Cyclophosphamide,
• Diethylsilbestrol,
• Etoposide combined with cisplastine and bleomycine,
• Yperite,
• Helicobacter pylori infections,
• Radioactive iodine,
• Melphalan,
• Methoxy-8-psoralen,
• MOPP,
• Neutrons,
• N-nitrosonornicotine,
• Estrogen therapy,
• Phosphorous 32 (in the form of phosphate),
• Plutonium 239 and 240,
• Radioelements emitting alpha and beta particles,
• Radium 224,226,228,222,
• X and gamma rays,
• Tamoxifene,
• TCDD,
• Thiotepa,
• Thorium 232
• And many viruses.

We will not mention here lists of mixtures and detailed occupational carcinogen exposures in the IARC list.

Other differences give rise to questions

These classification differences can no doubt be explained by the limits of animal testing and other differences in interpretation of human and experimental data but must question ourselves.
For greater safety and security, it seems logical to consider that the classification the most restrictive must be respected but this requires a clear understanding of the various lists.

These lists are reviewed inPROMETRA and meet the following classification:

• 1001: list of carcinogenous chemicals or suspected by the IARC
• 1020: list of carcinogens or suspected according to the ACGIH
• 1030: list of carcinogens or suspected according to the European Union (CLP)

Centre International de Recherche sur le Cancer
American Conference of Industrial Hygienists
Classification Labelling and Packaging of substances and mixtures, (CE) n°1272/2008

Danielle Henny, Occupational Health Physician

By the end of 2010, an estimated 569,490 Americans will have died from cancer. That's more than 1,500 people every day, and 1 out of every 4 deaths in this country [source: American Cancer Society]. So what is giving cancer such a push?

Well, as it turns out, in addition to cancer being hereditary, external factors are at play. For example, about 171,000 of this year's cancer deaths are believed to be caused by tobacco use [source: American Cancer Society]. How is it that external factors like tobacco use can have such a heavy hand in our cancer rates? It all comes down to carcinogens -- cancer-causing agents, like pollutants in the air, ultraviolet (UV) rays and viruses. How and why do carcinogens give cancer the upper hand?

Advertisement

Advertisement

Carcinogens are typically any external causes of cancer, excluding those without a hereditary link. However, for the purpose of this article, we're referring to the following categories of carcinogens from the World Health Organization (WHO):

• Biological (e.g., types of bacteria)
• Chemical (e.g., chemicals in tobacco smoke and asbestos)
• Physical (e.g., UV radiation)

What Are Carcinogens Definition

[source: World Health Organization]

Exposures to these 'agents of evil' can cause some wacky changes to our cells that lead to cancer. For example, some carcinogens can directly cause genetic mutations that foster abnormal cell growth and tumors. Others don't attack our genes directly, but trick our cells into cell division overdrive. That excess division then leads to potential genetic mutations down the road [source: American Cancer Society].

Does this mean that any exposure to a known carcinogen will cause you to develop cancer? The candid answer is, 'It depends.' For one, our genes are under continual attack by genetic mutations, but our DNA usually does a stellar job of repairing itself. That said, though, that 'repairman' skill isn't equal among all of us. Some of us do a better job of repairing our genes than others, which means that some people are more naturally susceptible to the negative effects of a carcinogen. Furthermore, a carcinogen's link to cancer can depend on:

• Age and gender
• Potency: Some carcinogens require pretty heavy exposure to be dangerous, while others are linked to cancer with just a brief exposure.
• Exposure type: For example, were you exposed to a carcinogen one time or continually over a period of years?

Level 1 Carcinogen

[source: National Cancer Institute]

If all of these factors have a role in just how much a carcinogen is linked to cancer, you may be wondering how you can determine what to look out for in your daily life. Or maybe you just want to know what known carcinogens even exist and how we find out about their danger. Advance to the next page to learn how we determine which substances to keep at arm's length.

Advertisement

Imagine being on the team in charge of figuring out the known carcinogens around us. You wouldn't be able to wrap up your project all neat and tidy, filing it away marked complete. Instead, you would continue to research and refine your list, working on new revisions every couple of years. After all, your research would be linked to potentially preventing cancer, which is a matter of life and death.

In the last government report on carcinogens -- known as the '11th Report on Carcinogens (RoC)' -- 246 substances made it on the list. Of those substances, 58, such as alcoholic beverages, benzene, mustard gas and coal tars, were identified as known human carcinogens, while the other 188 were not as strongly labeled. Instead, they were referred to as 'reasonably anticipated' to be substances linked to cancer [source: National Toxicology Program].

Advertisement

Advertisement

What Are 4 Carcinogens Found In Tobacco

So just how does a substance make it on the list? Scientists rely on two different types of studies: lab and epidemiologic. In a laboratory environment, scientists are limited in what they can do, since they can't test on people. Therefore, they have to rely on cell cultures and animal testing. However, even that isn't enough because replicating exposures in people isn't possible, and it's impossible to say that a substance will act the same way in humans as it did in animals. Furthermore, to be able to use small sample groups, scientists must use doses markedly higher than human exposures when testing on animals. So scientists believe that positive carcinogen tests on animals are reasonable predictors of cancer risk and a justified reason to limit human exposure.

Group 1 Carcinogens List

In contrast to laboratory studies, epidemiologic studies, also known as population-based studies, take research outside of the lab. In an epidemiologic study, researchers look at a population of people and target potential causes of cancer. The challenge here is that outside of the lab, scientists lose a controlled environment, meaning it's difficult to determine what someone is exposed to and when. Therefore, scientists aim to use the best of both worlds -- lab and epidemiologic studies -- to determine the carcinogens that are potentially life threatening.

And they're certainly life threatening, indeed. In fact, it's believed that 75 to 80 percent of cancer deaths in the United States are due to exposure to carcinogens rather than hereditary links to cancer [source: American Cancer Society]. However, that doesn't mean that we should all hide under a rock; there might be a carcinogen under that rock anyway. Instead, we can take a role in our own protection by limiting our contacts to known carcinogens. For example, staying away from tobacco, limiting alcohol consumption and avoiding too much sun exposure are all wise steps toward prevention. Just remember, keep your wits about you, and there are things you can do to stop some of those carcinogens in their tracks.

Advertisement

Related Articles

Group 4 Carcinogen

Sources

• American Cancer Society. 'Cancer Facts & Figures 2010.' 2010. (Aug. 9, 2010) http://www.cancer.org/acs/groups/content/@nho/documents/document/acspc-024113.pdf
• American Cancer Society. 'Known and Probable Human Carcinogens.' (Aug. 9, 2010) http://www.cancer.org/Cancer/CancerCauses/OtherCarcinogens/GeneralInformationaboutCarcinogens/known-and-probable-human-carcinogens
• National Cancer Institute. 'Cancer and the Environment.' September 1, 2006. (Aug. 10, 2010)
• National Toxicology Program. '11^th Report on Carcinogens (RoC). (Aug. 31, 2010)http://ntp.niehs.nih.gov/index.cfm?objectid=E99AEB57-F1F6-975E-7BC5F9D939187D34
• World Health Organization. 'Cancer.' February 2009. (Aug. 9, 2010) http://www.who.int/mediacentre/factsheets/fs297/en/