What substance is known to produce cancer?

Answer 1

Substances that are known to cause cancer are called "carcinogens".

The list of known carcinogens is rather extensive.

Several different organizations publish lists of known carcinogens including:

• International Agency for Research on Cancer (IARC)

• National Toxicology Program (NTP) - which includes parts of several different US government agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA). The NTP updates its Report on Carcinogens (RoC) every few years.
• US Environmental Protection Agency (EPA)
• US CDC's National Institute for Occupational Safety and Health (NIOSH)
• US Food and Drug Administration (FDA)
• National Cancer Institute (NCI)

As of November 2016 IARC lists the following as "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 which 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

The NTP 14th Report on Carcinogens "Known to be human carcinogens lists"

• Aflatoxins
• Alcoholic beverage consumption
• 4-Aminobiphenyl
• Analgesic mixtures containing phenacetin
• Aristolochic acids
• Arsenic and inorganic arsenic compounds
• Asbestos
• Azathioprine
• Benzene
• Benzidine
• Beryllium and beryllium compounds
• Bis(chloromethyl) ether and technical-grade chloromethyl methyl ether
• 1,3-Butadiene
• 1,4-Butanediol dimethylsulfonate (also known as busulfan)
• Cadmium and cadmium compounds
• Chlorambucil
• 1-(2-Chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU)
• Chromium hexavalent compounds
• Coal tar pitches
• Coal tars
• Coke oven emissions
• Cyclophosphamide
• Cyclosporin A
• Diethylstilbestrol (DES)
• Dyes metabolized to benzidine
• Epstein-Barr virus (EBV)
• Erionite
• Estrogens, steroidal
• Ethylene oxide
• Formaldehyde
• Hepatitis B virus
• Hepatitis C virus
• Human immunodeficiency virus type 1 (HIV-1)
• Human papilloma viruses: some genital-mucosal types
• Human T-cell lymphotropic virus type 1 (HTLV-1)
• Kaposi sarcoma-associated herpesvirus (KSHV) (also known as human herpesvirus 8, or HHV-8)
• Melphalan
• Merkel cell polyomavirus (MCV)
• Methoxsalen with ultraviolet A therapy (PUVA)
• Mineral oils (untreated and mildly treated)
• Mustard gas
• 2-Naphthylamine
• Neutrons
• Nickel compounds
• Oral tobacco products
• Radon
• Silica, crystalline (respirable size)
• Solar radiation
• Soots
• Strong inorganic acid mists containing sulfuric acid
• Sunlamps or sunbeds, exposure to
• Tamoxifen
• 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD); "dioxin"
• Thiotepa
• Thorium dioxide
• Tobacco smoke, environmental
• Tobacco, smokeless
• Tobacco smoking
• o‑Toluidine
• Trichloroethylene (TCE)
• Vinyl chloride
• Ultraviolet (UV) radiation, broad spectrum
• Wood dust
• X-radiation and gamma radiation

Note that there is extensive overlap between these two lists although in some cases the same thing is listed somewhat differently.

Answer 2

There are a few KNOWN human carcinogens. Among them are asbestos, benzene and radioactive materials such as radium, uranium, plutonium, radon, etc.