Agent | Volume† | Year† | Primary exposure routes‡ | Human cancers with sufficient evidence§ | Quantitative exposure- response data available | Included in Siemiatycki et al 9 | Included in Doll and Peto3 | Occupational exposure settings¶ | Class | ||
Ingestion | Inhalation | Dermal contact | |||||||||
1,2-Dichloropropane | 110 | 2017 | x | Biliary tract | Manufacture of plastic products, paints and other chemicals; printing; car painting | Chemicals | |||||
1,3-Butadiene | 97 | 2008 | x | Haematolymphatic organs | x | Manufacture of industrial chemicals, rubber products and plastic products; petroleum refining and petrochemical industries; building construction | Chemicals | ||||
2-Naphthylamine | 4 | 1973 | x | x | Urinary bladder | x | x | Manufacture of industrial chemicals and dyes | Chemicals | ||
2,3,7,8-Tetrachlorodibenzo-para-dioxin | 69 | 1997 | x | x | x | All cancers combined | x | x | Manufacture of chemicals; herbicide handling and spraying; waste incineration | Chemicals | |
4-Aminobiphenyl | 1 | 1972 | x | x | Urinary bladder | x | x | Manufacture of chemicals and rubber | Chemicals | ||
Acid mists, strong inorganic | 54 | 1992 | x | x | x | Larynx | x | Manufacture of soaps and detergents, phosphate fertilisers, lead batteries and other chemicals; electroplating and pickling | Airborne particles | ||
Arsenic and inorganic arsenic compounds† | 2 | 1973 | x | x | Lung, skin, bladder | x | x | x | Manufacture of glass, pesticides and other chemicals; agricultural settings; mining, smelting and refining of metals; medical and veterinary procedures | Metals and metal compounds | |
Asbestos (all forms, including actinolite, amosite, anthophyllite, chrysotile, crocidolite, tremolite) | 2 | 1973 | x | Lung, mesothelioma, larynx, ovary | x | x | x | Mining, processing, transportation and handling of asbestos; work in shipyards; manufacture and use of asbestos-containing products | Airborne particles | ||
Benzene | 7 | 1974 | x | x | Leukaemia (acute myeloid) | x | x | x | Manufacture and use of paints, rubber products, glues and other chemicals; distribution and handling of petrol; shoe manufacturing and repair | Chemicals | |
Benzidine | 1 | 1972 | x | x | Bladder | x | x | Manufacture of chemicals, dyes, rubbers and plastics | Chemicals | ||
Beryllium and beryllium compounds | 58 | 1993 | x | x | Lung | x | x | Beryllium extraction, processing and fabrication; manufacture of electrical equipment, electronic components, aerospace materials; dental laboratory procedures | Metals and metal compounds | ||
Bis(chloromethyl)ether; chloromethyl methyl ether (technical grade) | 4 | 1974 | x | Lung | x | Yes | Manufacture of chemicals; laboratory procedures | Chemicals | |||
Cadmium and cadmium compounds | 58 | 1993 | x | Lung | x | x | Production, refining, and processing of cadmium and its alloys; manufacture of batteries and pigments | Metals and metal compounds | |||
Chromium (VI) compounds | Sup 7 | 1987 | x | Lung | x | x | Yes | Production and use of chromate pigments and paints; chrome plating; work in chrome-alloy foundries | Metals and metal compounds | ||
Coal-tar pitch | 35 | 1985 | x | x | Lung, skin | x | Production of coal-tar products; roofing and surface coating activities | Chemical mixtures | |||
Engine exhaust, diesel | 105 | 2013 | x | Lung | x | Rail, truck, and bus operation and mechanical maintenance; mining; firefighting | Airborne complex mixtures | ||||
Formaldehyde | 88 | 2006 | x | x | Nasopharynx, leukaemia | x | Manufacture of formaldehyde and other chemicals; histopathology and anatomy dissections; hospital disinfection; embalming | Chemicals | |||
Ionising radiation (all types)** | 100D | 2012 | None specified | x | x | x | Outdoor work involving sun exposure; nuclear fuel production and use; air travel; mining; human and veterinary medicine | Radiation and radionuclides | |||
Leather dust | 25 | 1981 | x | Nasal cavity and paranasal sinus | Manufacture, processing and repair of leather, boots and shoes | Airborne particles | |||||
Lindane (see also hexachlorocyclohexanes) | 113 | 2015* | x | x | Non-Hodgkin’s lymphoma | x | Manufacture of lindane; treatment of wood and wooden structures; agricultural application on livestock and crops | Chemicals | |||
Mineral oils, untreated or mildly treated | 3 | 1973 | x | x | Skin | x | Paraffin processing; manufacture of metal products; metal working | Chemical mixtures | |||
Nickel compounds | 49 | 1990 | x | x | x | Lung, nasal cavity and paranasal sinuses | x | x | x | Mining, smelting and refining of nickel; production of nickel alloys, stainless steel and batteries; electroplating; paint production and use | Metals and metal compounds |
ortho-Toluidine | 99 | 2010 | x | x | Urinary bladder | Manufacture of ortho-toluidine and dyes, pigments, and some rubber chemicals; clinical and pathological laboratories | Chemicals | ||||
Outdoor air pollution** | 109 | 2016 | x | Lung | x | Where majority of working time is spent in polluted outdoor environments (eg, urban traffic police, professional drivers, street vendors) | Airborne particles | ||||
Particulate matter in outdoor air pollution | 109 | 2016 | x | Lung | x | Airborne particles | |||||
Pentachlorophenol | 117 | 2016* | x | x | Non-Hodgkin’s lymphoma | x | Manufacture of PCP and other chemicals; agricultural settings; treatment of wood products; waste incineration | Chemicals | |||
Plutonium | 78 | 2001 | Bone, liver, lung | x | Nuclear industry workers | Radiation and radionuclides | |||||
Polychlorinated biphenyls | 107 | 2016 | x | x | Malignant melanoma | x | Manufacture of PCB capacitors; manufacture and repair of transformers; waste incineration and recycling; firefighting | Chemical mixtures | |||
Radioiodines, including iodine-131†† | 78 | 2001 | Thyroid | x | Workers involved in nuclear accident clean-up | Radiation and radionuclides | |||||
Radionuclides, alpha-particle emitting, internally deposited** | 78 | 2001 | None specified | x | Mining and processing of uranium and other minerals; nuclear industry workers; human and veterinary medicine | Radiation and radionuclides | |||||
Radionuclides, beta-particle emitting, internally deposited** | 78 | 2001 | None specified | x | Radiation and radionuclides | ||||||
Radium-224 and its decay products§ | 78 | 2001 | Bone | Luminising industries | Radiation and radionuclides | ||||||
Radium-226 and its decay products | 78 | 2001 | Bone, mastoid process, paranasal sinus | Radiation and radionuclides | |||||||
Radium-228 and its decay products | 78 | 2001 | Bone, mastoid process, paranasal sinus | Radiation and radionuclides | |||||||
Radon-222 and its decay products | 43 | 1988 | Lung | x | Mining and other underground work; mineral processing | Radiation and radionuclides | |||||
Shale oils | 35 | 1985 | x | Skin | x | Mining and production of shale oils and products; manufacturing of cotton textiles | Chemical mixtures | ||||
Silica dust, crystalline, in the form of quartz or cristobalite | 68 | 1997 | x | Lung | x | x | Mining and quarrying operations; foundries; ceramics, cement and glass industries; construction activities | Airborne particles | |||
Solar radiation** | 55 | 1992 | Skin (basal cell carcinoma, squamous cell carcinoma, melanoma) | x | Outdoor work with sun exposure | Radiation and radionuclides | |||||
Soot | 3 | 1973 | x | x | Lung, skin | x | x | Industries and tasks with exposure to combustion products (eg, coke-making, chimney cleaning, incineration) | Airborne particles | ||
Sulfur mustard (see also mustard gas) | 9 | 1975 | x | Lung | x | x | Manufacture of mustard gas; military service in WWI | Chemicals | |||
Tobacco smoke, secondhand** | 83 | 2004 | x | Lung | Work in public settings where smoking occurs (eg, restaurants, bars, casinos, planes) | Airborne complex mixtures | |||||
Trichloroethylene | 106 | 2014 | x | x | Kidney | Manufacture of metals and plastic products; printing; textile furnishing; dry cleaning; construction | Chemicals | ||||
Ultraviolet radiation** | 118 | 2017* | Eye, skin | x | x | Various work environments where welding is performed | Radiation and radionuclides | ||||
Vinyl chloride | 7 | 1974 | x | Liver (angiosarcoma, hepatocellular carcinoma) | x | x | x | Manufacture of polyvinyl chloride | Chemicals | ||
Welding fumes | 118 | 2017* | x | Lung | x | Various work environments where welding is performed | Airborne particles | ||||
Wood dust | 62 | 1995 | x | Nasal cavity and paranasal sinus, nasopharynx | x | x | Forestry and logging; sawmilling; manufacture of wood products; carpentry; construction | Airborne particles | |||
X-radiation and gamma-radiation** | 75 | 2000 | Multiple, including: breast; leukaemia; thyroid; bone; brain and central nervous system; colon; kidney; lung; oesophagus; salivary gland; skin; stomach; bladder | x | Nuclear industry workers; human and veterinary medicine; workers involved in nuclear accident clean-up | Radiation and radionuclides |
*Monographs still in press.
†Volume and year of publication correspond to the first instance of a Group 1 classification for the agent.
‡Routes not listed for radiations and radionuclides
§The cancer sites listed reflect the most recent IARC evaluation of the agent.
¶Examples of potentially exposed industries, work locations and/or occupations described in the relevant monograph; do not represent exhaustive summaries of past and present exposure scenarios.
**Occupational and non-occupational data contributed to first Group 1 evaluation.
††Occupational data contributed to subsequent Group 1 evaluation.
IARC, International Agency for Research on Cancer; PCB, polychlorinated biphenyl; PCP, pentachlorophenol; WWI, First World War.