Carcinogen

A carcinogen is any substance capable of causing cancer.[1] Carcinogens do not always cause cancer. Risk factors include the length and intensity of exposure and the genetic makeup of the individual.[2]

## Contents

* 1 Identification
* 2 Classification
* 2.1 International Agency for Research on Cancer
* 2.2 National Toxicology Program
* 3 Specific carcinogens
* 3.1 Commonplace examples
* 3.1.1 Disputed examples
* 3.2 Known carcinogens
* 4 Probably carcinogens
* 5 References
* 6 External links

## Identification[edit]

Laboratory studies are the primary source for identifying carcinogens. In these studies, it is assumed that if a large dose (usually higher than common human exposure) of a substance causes cancer in cell cultures or animals it will also cause cancer in humans.[2]

Epidemiologic studies are another importance source of information about carcinogens. These focus on the interactions of human populations with the substances found in their environments. It is difficult to identify carcinogens through these studies because of their uncontrolled nature, but they aid scientists in making educated assessments of the cancer-causing ability of suspected carcinogens.[2]

## Classification[edit]

Carcinogens are classified by the International Agency for Research on Cancer and the National Toxicology Program.

### International Agency for Research on Cancer[edit]

The International Agency for Research on Cancer (IARC), of the World Health Organization, produces the most widely used system[2] for classifying carcinogens in its Monographs (published since 1971[3]). Substances are classified by IARC as to their carcinogenic hazard to humans: Established, Probable, Possible, Unclassifiable, and Not probable.[4] The group qualifiers probable and possible have no quantitative significance but are used as descriptors of different levels of evidence of human carcinogenicity.[5]

### National Toxicology Program[edit]

The National Toxicology Program (NTP), of the U.S. Department of Health and Human Services, classifies carcinogens in two categories: Known, and Reasonably anticipated.[6] Since 1978, it has produced a list of carcinogenic material along with federal regulations limiting exposure.[6]

## Specific carcinogens[edit]

### Commonplace examples[edit]

The following are common-place examples of carcinogens:

* Alcoholic beverages (forming acetaldehyde)
* Asbestos
* Asphalt fumes
* Chloroform
* Diesel exhaust
* Gasoline
* Nickel[7]
* Solar radiation
* Soot
* Tobacco products
* X-Radiation

#### Disputed examples[edit]

* Estrogen[8]
* Bisphenol A (BPA), Bisphenol S (BPS), and Bisphenol F (BPF) - some studies find BPA carcinogenic,[9] others do not.[10] BPS and BPF are very similar, and so are suspected by some to have similar health effects, if any.

### Known carcinogens[edit]

The following is a more exhaustive list of known carcinogens:[11]

* 1-(2-Chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU)
* 1,2-Dichloropropane
* 1,3-Butadiene
* 1,4-Butanediol dimethylsulfonate (also known as busulfan)
* 2-Naphthylamine
* 2,3,4,7,8-Pentachlorodibenzofuran
* 2,3,7,8-Tetrachlorodibenzo-para-dioxin (TCDD); "dioxin"
* 3,4,5,3',4'-Pentachlorobiphenyl (PCB-126)
* 4-Aminobiphenyl
* 4,4'-Methylenebis(chloroaniline) (MOCA)
* Acetaldehyde (from consuming alcoholic beverages)
* Acheson process, occupational exposure associated with
* Acid mists, strong inorganic
* Aflatoxins (from fungus sometimes found in improperly stored crops such as corn, peanuts, cottonseed, and tree nuts. The fungi Aspergillus flavus and Aspergillus parasiticus are the main sources of this toxin)
* Aluminum production
* Analgesic mixtures containing phenacetin
* Areca nut[12]
* Aristolochic acids
* Arsenic and inorganic arsenic compounds
* Asbestos (all forms) and mineral substances (such as talc or vermiculite) that contain asbestos
* Auramine production
* Azathioprine
* Benzene
* Benzidine and dyes metabolized to benzidine
* Benzo[a]pyrene
* Beryllium and beryllium compounds
* Betel quid, with or without tobacco
* Bis(chloromethyl) ether and technical-grade chloromethyl methyl ether
* Busulfan (drug used for treating leukemia, and destroying bone marrow prior to a transplant)
* Cadmium and cadmium compounds (used in batteries, alloys, coatings (electroplating), solar cells, plastic stabilizers, and pigments)[13][14]
* Chlorambucil (trademarked "Leukeran" and other names, this is a drug used for treating cancer)[15][16]
* Chlornaphazine (a nitrogen mustard, formerly a drug used to treat polycythemia and Hodgkin's disease)
* Chromium (VI) compounds
* Clonorchis sinensis (infection with), also known as the Chinese liver fluke
* Coal gasification
* Coal tars
* Coal-tar pitch
* Coal, indoor emissions from household combustion
* Coke oven emissions
* Coke production
* Cyclophosphamide
* Cyclosporin A
* Cyclosporine (ciclosporin)
* Diethylstilbestrol (DES)
* Dyes metabolized to benzidine
* Engine exhaust, diesel
* Epstein-Barr virus (EBV) (infection with)
* Erionite[17]
* Estrogen-only menopausal therapy
* Estrogen-progestogen (menopausal therapy, oral contraceptives)
* Estrogens, steroidal
* Ethanol in alcoholic beverages
* Ethylene oxide (i.e. oxirane, used in the production of solvents, antifreeze, textiles, detergents, adhesives, and polyurethane foam)[18]
* Etoposide (trademarked Etopophos, a medication sometimes used to treat neoplastic diseases)[19]
* Etoposide in combination with cisplatin and bleomycin
* Fission products, including strontium-90
* Fluoro-edenite fibrous amphibole (inhalation of dust, similar to asbestos)[20]
* Formaldehyde
* Haematite mining (underground)
* Helicobacter pylori (infection with)
* Hepatitis B virus (chronic infection with)
* Hepatitis C virus (chronic infection with)
* Human immunodeficiency virus type 1 (HIV-1) (infection with)
* Human papilloma virus (HPV) types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 (infection with)
* Human T-cell lymphotropic virus type I (HTLV-1) (infection with)
* Ionizing radiation (all types)
* Iron and steel founding (workplace exposure)
* Isopropyl alcohol manufacture using strong acids
* Kaposi sarcoma herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8) (infection with)
* Leather dust
* Lindane (i.e. gamma-hexachlorocyclohexane, gammaxene, or Gammallin; used for treating scabies and lice)[21][22]
* Magenta production
* Melphalan (an alkylating agent trademarked as Alkeran; treatment for multiple myeloma and a certain type of ovarian cancer)[23]
* Merkel cell polyomavirus (MCV)
* Methoxsalen (8-methoxypsoralen) plus ultraviolet A radiation, also known as PUVA
* Methyl-CCNU
* Mineral oils (untreated and mildly treated)
* MOPP and other combined chemotherapy including alkylating agents
* Mustard gas (i.e. sulfur mustard)
* N'-Nitrosonornicotine (NNN) and 4-(N-Nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK)
* Neutron radiation
* Nickel compounds
* o‑Toluidine
* Opisthorchis viverrini (infection with), also known as the Southeast Asian liver fluke
* ortho-Toluidine
* Outdoor air pollution (and the particulate matter in it)
* Painter (workplace exposure as a)
* Pentachlorophenol
* Phenacetin (and mixtures containing it)
* Phosphorus-32, as phosphate
* Plutonium
* Polychlorinated biphenyls (PCBs), dioxin-like, with a Toxicity Equivalency Factor according to WHO (PCBs 77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169, 189)
* Processed meat (consumption of)
* Radioiodines, including iodine-131
* Radionuclides, alpha-particle-emitting, internally deposited
* Radionuclides, beta-particle-emitting, internally deposited
* Radium-224 and its decay products
* Radium-226 and its decay products
* Radium-228 and its decay products
* Radon-222 and its decay products
* Rubber manufacturing
* Salted fish (Chinese-style)
* Schistosoma haematobium (infection with)
* Semustine (methyl-CCNU)
* Shale oils
* Silica dust, crystalline, in the form of quartz or cristobalite
* Solar radiation
* Soot (as found in workplace exposure of chimney sweeps)
* Strong inorganic acid mists containing sulfuric acid
* Sunlamps or sunbeds, exposure to
* Talc containing asbestiform fibres
* Tamoxifen (estrogen blocking drug, sometimes used to treat or prevent cancer)[24]
* Thiotepa (drug used for treating cancer)[25]
* Thorium dioxide (used in high-temperature ceramics, gas mantles, crucibles, non-silicia optical glass, catalysis, filaments in incandescent lamps, cathodes in electron tubes and arc-melting electrodes)[26]
* Thorium-232 and its decay products
* Tobacco smoke
* Tobacco, smokeless
* Treosulfan (cancer treatment)[27][28]
* Trichloroethylene (TCE) (grease solvent, also used in adhesives, paint removers, typewriter correction fluids, and spot removers)[29][30]
* Ultraviolet (UV) light, including UVA, UVB, and UVC rays
* Vinyl chloride (used in the production of PVC plastics)
* Welding fumes
* Wood dust
* X-radiation and gamma radiation

## Probably carcinogens[edit]

The following is a semi-exhaustive list of "probable" carcinogens:[31]

* Acrylamide
* Adriamycin (doxorubicin)
* Androgenic (anabolic) steroids
* Art glass, glass containers, and press ware (manufacture of)
* Azacitidine
* Biomass fuel (primarily wood), emissions from household combustion
* Bitumens, occupational exposure to oxidized bitumens and their emissions during roofing
* Bischloroethyl nitrosourea (BCNU), also known as carmustine
* Captafol (fungicide)[32]
* Carbon electrode manufacture
* Chloral
* Chloral hydrate
* Chloramphenicol
* alpha-Chlorinated toluenes (benzal chloride, benzotrichloride, benzyl chloride) and benzoyl chloride (combined exposures)
* 1-(2-Chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU)
* 4-Chloro-ortho-toluidine
* Chlorozotocin
* Cisplatin (chemotherapy medication used for treating certain kinds of cancer, also used to treat renal toxicity and renal failure)
* Cobalt metal with tungsten carbide
* Creosotes
* Cyclopenta[cd]pyrene
* DDT (4,4'-Dichlorodiphenyltrichloroethane)
* Diazinon (insecticide)[33]
* Dibenz[a,j]acridine
* Dibenz[a,h]anthracene
* Dibenzo[a,l]pyrene
* Dichloromethane (methylene chloride)
* Dieldrin, and aldrin metabolized to dieldrin
* Diethyl sulfate
* Dimethylcarbamoyl chloride
* N,N-Dimethylformamide
* 1,2-Dimethylhydrazine
* Dimethyl sulfate (an alkylating agent used in manufacture of many organic chemicals)[34]
* Epichlorohydrin
* Ethyl carbamate (urethane)
* Ethylene dibromide
* N-Ethyl-N-nitrosourea
* Frying, emissions from high-temperature
* Glycidol (used as a stabilizer for natural oils and vinyl polymers, as an alkylating agent, a sterilant, a demulsifier, and more)[35]
* Glyphosate (herbicide, the active ingredient in many weed killers including RoundUp, also used in farming, and thus found in many foods.[36])[37]
* Hairdresser or barber (workplace exposure as)
* Human papillomavirus (HPV) type 68 (infection with)
* Hydrazine (Small quantities occur naturally in plants; most are manufactured for use as rocket propellants and fuels, boiler water treatments, chemical reactants, medicines, and used in cancer research).[38]
* Indium phosphide (used in electronic semiconductors, injection lasers, and solar cells.)[39]
* IQ (2-Amino-3-methylimidazo[4,5-f]quinoline)
* Lead compounds, inorganic
* Malaria (caused by infection with Plasmodium falciparum)
* Malathion (insecticide)
* 2-Mercaptobenzothiazole
* Merkel cell polyomavirus (MCV)
* 5-Methoxypsoralen
* Methyl methanesulfonate (i.e. methyl mesylate)
* N-Methyl-N´-nitro-N-nitrosoguanidine (MNNG)
* N-Methyl-N-nitrosourea
* Nitrate or nitrite (ingested) under conditions that result in endogenous nitrosation
* 6-Nitrochrysene
* Nitrogen mustard
* 1-Nitropyrene
* N-Nitrosodiethylamine
* N-Nitrosodimethylamine
* 2-Nitrotoluene
* Non-arsenical insecticides (workplace exposures in spraying and application of)
* Petroleum refining (workplace exposures in)
* Pioglitazone
* Polybrominated biphenyls (PBBs)
* Procarbazine hydrochloride
* 1,3-Propane sultone
* Red meat (consumption of)
* Shiftwork that involves circadian disruption
* Silicon carbide whiskers
* Styrene
* Styrene-7,8-oxide
* Teniposide
* Tetrabromobisphenol A
* 3,3′,4,4′-Tetrachloroazobenzene
* Tetrachloroethylene (perchloroethylene)
* Tetrafluoroethylene (used in the production of polytetrafluoroethylene resins, and as a propellant for food product aerosols)[40]
* 1,2,3-Trichloropropane
* Tris(2,3-dibromopropyl) phosphate
* Very hot beverages (above 65 degrees Celsius)
* Vinyl bromide (Note: For practical purposes, vinyl bromide should be considered to act similarly to the human carcinogen vinyl chloride.)

## References[edit]

1. ↑ Compact Oxford English Dictionary.
2. ↑ 2.0 2.1 2.2 2.3 American Cancer Society: Known and Probable Carcinogens
3. ↑ http://monographs.iarc.fr/index.php
4. ↑ IARC: Classifications
5. ↑ Group definitions.
6. ↑ 6.0 6.1 National Toxicology Progam: Questions & Answers about the RoC.
7. ↑ Kasprzak KS, Sunderman FW Jr, Salnikow K. Nickel carcinogenesis
8. ↑ Feds label estrogen carcinogen
9. ↑ http://blogs.edf.org/health/2014/02/21/is-bpa-a-carcinogen/
10. ↑ https://toxnet.nlm.nih.gov/cpdb/chempages/BISPHENOL A.html
11. ↑ https://monographs.iarc.fr/cards_page/publications-monographs/
12. ↑ https://www.drugs.com/npc/betel-nut.html
13. ↑ https://www.osha.gov/SLTC/cadmium/
14. ↑ https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/cadmium
15. ↑ https://www.drugs.com/mtm/chlorambucil.html
16. ↑ https://www.webmd.com/drugs/2/drug-14006/chlorambucil-oral/details
17. ↑ https://www.mindat.org/min-1399.html
18. ↑ https://www.cdc.gov/niosh/topics/ethyleneoxide/default.html
19. ↑ https://www.drugs.com/pro/etoposide.html
20. ↑ https://www.mindat.org/min-6950.html
21. ↑ https://medlineplus.gov/druginfo/meds/a682651.html
22. ↑ https://www.drugs.com/pro/lindane.html
23. ↑ https://medlineplus.gov/druginfo/meds/a682220.html
24. ↑ https://www.drugs.com/tamoxifen.html
25. ↑ https://www.rxlist.com/thiotepa-drug.htm
26. ↑ https://pubchem.ncbi.nlm.nih.gov/compound/Thorium-dioxide
27. ↑ https://treosulfan.com/
28. ↑ https://www.cancerresearchuk.org/about-cancer/cancer-in-general/treatment/cancer-drugs/drugs/treosulfan
29. ↑ https://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=30
30. ↑ https://pubchem.ncbi.nlm.nih.gov/compound/trichloroethylene
31. ↑ https://www.cancer.org/cancer/cancer-causes/general-info/known-and-probable-human-carcinogens.html
32. ↑ https://pubchem.ncbi.nlm.nih.gov/compound/Captafol
33. ↑ http://npic.orst.edu/factsheets/Diazgen.html
34. ↑ https://ncit.nci.nih.gov/ncitbrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&ns=NCI_Thesaurus&code=C44377
35. ↑ https://ncit.nci.nih.gov/ncitbrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&ns=NCI_Thesaurus&code=C44387
36. ↑ https://www.healthyandnaturalworld.com/glyphosate-in-food-complete-list/
37. ↑ https://www.epa.gov/ingredients-used-pesticide-products/glyphosate
38. ↑ https://pubchem.ncbi.nlm.nih.gov/compound/hydrazine
39. ↑ https://pubchem.ncbi.nlm.nih.gov/compound/Indium-phosphide#section=Uses
40. ↑ https://www.britannica.com/science/tetrafluoroethylene

## External links[edit]

* National Institute for Occupational Safety and Health (part of the CDC): Carcinogen List
* Cancer.org list of carcinogens
* Full text to the Preamble to the IARC Monographs
* NTP: 11th Report on Carcinogens
* NTP: List of Known Carcinogens