Toxic Carcinogens

A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis, the formation of cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substances are considered carcinogens, but their carcinogenic activity is attributed to the radiation, for example gamma rays and alpha particles, which they emit. Common examples of non-radioactive carcinogens are inhaled asbestos, certain dioxins, and tobacco smoke. Although the public generally associates carcinogenicity with synthetic chemicals, it is equally likely to arise in both natural and synthetic substances. Carcinogens are not necessarily immediately toxic; thus, their effect can be insidious.

Cancer is any disease in which normal cells are damaged and do not undergo programmed cell death as fast as they divide via mitosis. Carcinogens may increase the risk of cancer by altering cellular metabolism or damaging DNA directly in cells, which interferes with biological processes, and induces the uncontrolled, malignant division, ultimately leading to the formation of tumors.

Known and Probable Human Carcinogens

Many people worry that substances or exposures in their environment may cause cancer.

Cancer is caused by changes in a cell’s DNA – its genetic “blueprint.” Some of these changes may be inherited from our parents. Others may be caused by outside exposures, which are often referred to as environmental factors. Environmental factors can include a wide range of exposures, such as:

– Lifestyle factors (nutrition, tobacco use, physical activity, etc.)
– Naturally occurring exposures (ultraviolet light, radon gas, infectious agents, etc.)
– Medical treatments (radiation and medicines including chemotherapy, hormone drugs, drugs that suppress the immune system, etc.)
– Workplace exposures
– Household exposures
– Pollution

Substances and exposures that can lead to cancer are called carcinogens. Some carcinogens do not affect DNA directly, but lead to cancer in other ways. For example, they may cause cells to divide at a faster than normal rate, which could increase the chances that DNA changes will occur.

Carcinogens do not cause cancer in every case, all the time. Substances labeled as carcinogens may have different levels of cancer-causing potential. Some may cause cancer only after prolonged, high levels of exposure. And for any particular person, the risk of developing cancer depends on many factors, including how they are exposed to a carcinogen, the length and intensity of the exposure, and the person’s genetic makeup.

Known Human Carcinogens – International Agency for Research on Cancer

Group 1: Carcinogenic to Humans

– Acetaldehyde (from consuming alcoholic beverages)
– Acheson process, occupational exposure associated with
– Acid mists, strong inorganic
– Aflatoxins
– Alcoholic beverages
– Aluminum production
– 4-Aminobiphenyl
– Areca nut
– Aristolochic acid (and plants containing it)
– 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 chloromethyl methyl ether (technical-grade)
– Busulfan
– 1,3-Butadiene
– Cadmium and cadmium compounds
– Chlorambucil
– Chlornaphazine
– Chromium (VI) compounds
– Clonorchis sinensis (infection with), also known as the Chinese liver fluke
– Coal, indoor emissions from household combustion
– Coal gasification
– Coal-tar distillation
– Coal-tar pitch
– Coke production
– Cyclophosphamide
– Cyclosporine
– 1,2-Dichloropropane
– Diethylstilbestrol
– Engine exhaust, diesel
– Epstein-Barr virus (infection with)
– Erionite
– Estrogen postmenopausal therapy
– Estrogen-progestogen postmenopausal therapy (combined)
– Estrogen-progestogen oral contraceptives (combined) (Note: There is also convincing evidence in humans that -these agents confer a protective effect against cancer in the endometrium and ovary)
– Ethanol in alcoholic beverages
– Ethylene oxide
– Etoposide
– Etoposide in combination with cisplatin and bleomycin
– Fission products, including strontium-90
– Fluoro-edenite fibrous amphibole
– 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)
(Note: The HPV -types that have been classified as carcinogenic to humans can differ by an order of magnitude in risk for -cervical cancer)-
– 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
– Magenta production
– Melphalan
– Methoxsalen (8-methoxypsoralen) plus ultraviolet A radiation, also known as PUVA
– 4,4′-Methylenebis(chloroaniline) (MOCA)
– Mineral oils, untreated or mildly treated
– MOPP and other combined chemotherapy including alkylating agents
– 2-Naphthylamine
– Neutron radiation
– Nickel compounds
– N’-Nitrosonornicotine (NNN) and 4-(N-Nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK)
– Opisthorchis viverrini (infection with), also known as the Southeast Asian liver fluke
– Outdoor air pollution (and the particulate matter in it)
– Painter (workplace exposure as a)
– 3,4,5,3′,4′-Pentachlorobiphenyl (PCB-126)
– 2,3,4,7,8-Pentachlorodibenzofuran
– 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 (Note: Specific radionuclides for which there is -sufficient evidence for carcinogenicity to humans are also listed individually as Group 1 agents)-
– Radionuclides, beta-particle-emitting, internally deposited (Note: Specific radionuclides for whi-ch there is sufficient evidence for carcinogenicity to humans are also listed individually as Group 1 agents)
– 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 industry
– 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)
– Sulfur mustard
– Tamoxifen (Note: There is also conclusive evidence that tamoxifen reduces the risk of contralateral breast -cancer in breast cancer patients)
– 2,3,7,8-Tetrachlorodibenzo-para-dioxin
– Thiotepa
– Thorium-232 and its decay products
– Tobacco, smokeless
– Tobacco smoke, secondhand
– Tobacco smoking
– ortho-Toluidine
– Treosulfan
– Trichloroethylene
– Ultraviolet (UV) radiation, including UVA, UVB, and UVC rays
– Ultraviolet-emitting tanning devices
– Vinyl chloride
– Wood dust
– X- and Gamma-radiation
– National Toxicology Pro