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ChemicalLink to CancerScientific Evidence of Link to CancerHow to Minimize Exposure
Outdoors
Environmental quality as a wholeModestly increased risks of getting some cancers or of cancer mortality among people living in areas with poorer Environmental Quality Index scoresEnvironmental Quality Index is a composite measure of air, water, land, built, and sociodemographic qualities. Groups with poorer EQI scores have higher breast cancer incidences, more advanced prostate cancer at diagnosis, worse colorectal cancer surgery outcomes, and higher cancer mortality.1Gearhart-Serna LM, Mills BA et al. Cumulative environmental quality is associated with breast cancer incidence differentially by summary stage and urbanicity. Scientific Reports. 2023 Nov 20;13(1):20301; Vigneswaran H, Jagai J et al. Association between environmental quality and prostate cancer stage at diagnosis. Prostate Cancer & Prostatic Diseases. 2021;24(4):1129-1136.2Jian Y, Messer L et al. Associations between environmental quality and mortality in the contiguous United States, 2000-2005. Environmental Health Perspectives. 2017;125(3):355-362; Shaikh C, Woldesenbet S et al. Association between the environmental quality index and textbook outcomes among Medicare beneficiaries undergoing surgery for colorectal cancer (CRC). Journal of Surgical Oncology. 2023;27(7):1143-1151. More information and supporting studies can be found on the Collaborative for Health & Environment environmental hazards exposure sources information page.If possible, choose to live in a community with strong environmental regulations, green spaces, and low pollutions indices. In addition, for air: use HEPA air purifiers, and seal drafts to prevent polluted outside air from entering the house.
Water: Filter tap water for heavy metals or pesticides (especially if using private wells).
Land: Avoid gardening or playing near known contamination sites. Use raised garden beds with clean soil.
Built environment: Ensure good ventilation and reduce indoor chemical use.
Air pollution: fine particulate matter or nitrogen dioxideSmall increases in mortality risk from several cancers, including lung, bladder, colorectal, and kidney. Increased risks of developing brain, breast, leukemia, and other cancers.In meta-analyses and large population studies, fine particulate matter—smaller than 2.5 micrometers in diameter—is linked to higher mortality rates from bladder, colorectal, kidney cancers, colorectal and cancer as a whole. PM2.5 also increases the incidence of lung, brain, breast, mouth and throat, nonmelanoma skin, colorectal, and prostate cancers, as well as leukemia.3Fu P, Li R et al. Associations between fine particulate matter and colorectal cancer: a systematic review and meta-analysis. Reviews on Environmental Health. 2023;39(3):447-457; Luo G, Zhang Y et al. Estimated worldwide variation and trends in incidence of lung cancer by histological subtype in 2022 and over time: a population-based study. Lancet Respiratory Medicine. 2025 Apr;13(4):348-363; Coleman NC, Burnett RT et al. Cancer mortality risk, fine particulate air pollution, and smoking in a large, representative cohort of US adults. Cancer Causes & Control. 2020 Aug;31(8):767-776; Turner MC, Krewski D et al. Ambient air pollution and cancer mortality in the Cancer Prevention Study II. Environmental Health Perspectives. 2017 Aug 21;125(8):087013; Zhang D, Xi Y, Boffa DJ, Liu Y, Nogueira LM. Association of wildfire exposure while recovering from lung cancer surgery with overall survival. JAMA Oncology. 2023 Jul 27:e232144; Stieb DM, Berjawi R et al. Systematic review and meta-analysis of cohort studies of long term outdoor nitrogen dioxide exposure and mortality. PLoS One. 2021 Feb 4;16(2):e0246451; Weichenthal S, Olaniyan T et al. Within-city spatial variations in ambient ultrafine particle concentrations and incident brain tumors in adults. Epidemiology. 2020 Mar;31(2):177-183; White AJ, Fisher JA et al. Ambient fine particulate matter and breast cancer incidence in a large prospective US cohort. Journal of the National Cancer Institute. 2024 Jan 10;116(1):53-60; Datzmann T, Markevych I et al. Outdoor air pollution, green space, and cancer incidence in Saxony: a semi-individual cohort study. BMC Public Health. 2018 Jun 8;18(1):715; Goldberg MS, Villeneuve PJ et al. Associations between incident breast cancer and ambient concentrations of nitrogen dioxide from a national land use regression model in the Canadian National Breast Screening Study. Environment International. 2019 Dec;133(Pt B):105182; Wei T, Jiao R et al. Exposure to outdoor air pollution at different periods and the risk of leukemia: a meta-analysis. Environmental Science and Pollution Research International. 2021 Jul;28(27):35376-35391; Jephcote C, Brown D, Verbeek T, Mah A. A systematic review and meta-analysis of haematological malignancies in residents living near petrochemical facilities. Environmental Health. 2020 May 19;19(1):53 People exposed to nitrogen dioxide, a marker of traffic-related air pollution, may have a higher risk of lung cancer mortality.4Stieb DM, Berjawi R et al. Systematic review and meta-analysis of cohort studies of long term outdoor nitrogen dioxide exposure and mortality. PLoS One. 2021 Feb 4;16(2):e0246451. More information and supporting studies can be found on the Collaborative for Health & Environment air pollution information page.Monitor air quality using websites/apps such as PurpleAir.com, and avoid going outdoors when Air Quality Index is above 100. On days when air quality is poor, use a HEPA air filter at home, and N95 or KN95 respirator masks if going outdoors is unavoidable. Use a range hood to ventilate air when cooking. Weatherproof doors and windows to prevent air particulates from entering the home.
BenzeneIncreased risk of leukemia, and possible increased risk of lung cancer, non-Hodgkins lymphoma, nervous system and stomach cancersClassified as a Group 1 carcinogen by IARC,* meaning there is sufficient evidence that this chemical causes cancer in humans.5International Agency for Research on Cancer Monograph Working Group. Benzene. A review of human carcinogens, volume 120. World Health Organization. 2018. Benzene has been shown to cause leukemia.6Smith MT. Advances in understanding benzene health effects and susceptibility. Annual Review of Public Health. 2010;31:133-148; Wei T, Jiao R et al. Exposure to outdoor air pollution at different periods and the risk of leukemia: a meta-analysis. Environmental Science and Pollution Research International. 2021 Jul;28(27):35376-35391. Benzene is also linked to increased risks of lung cancer, non-Hodgkins lymphoma, nervous system cancer and stomach cancer.7DeMoulin D, Cai H, Vermeulen R, et al. Occupational benzene exposure and cancer risk among Chinese Men: a report from the Shanghai Men’s Health Study. Cancer Epidemiology, Biomarkers & Prevention. 2024;33:1465-1474; Wan W, Peters S et al. Occupational benzene exposure and lung cancer in human studies: a systematic review and meta-analysis. Environmental Health Perspectives. 2024;132(12):126001; Mangiaterra S, Boffetta P, Seyyedsalehi M. Occupational benzene exposure and risk of nervous system cancers: A systematic review and meta-analysis. Cancer Epidemiology. 2025;95:102779; Chiavarini M, Rosignoli P, Sorbara B, et al. Benzene exposure and lung cancer risk: a systematic review and meta-analysis of human studies. International Journal of Environmental Research and Public Health. 2024;21:205; Rana I, Dahlberg S, Steinmaus C, Zhang L. Benzene exposure and non-Hodgkin lymphoma: a systematic review and meta-analysis of human studies. Lancet Planetary Health. 2021 Sep;5(9):e633-e643; Liu Y, Wang J. Benzene exposure increases the risk of non-Hodgkin’s lymphoma: a systematic review and meta-analysis of observational studies. Translational Cancer Research. 2022;11(6):1750-1761.For most people, the most likely source of benzene exposure is cigarette smoke, so not smoking and avoiding secondhand smoke limit benzene exposure. Limit exposure to car exhaust and gasoline–do not idle car engines in closed spaces; do not sit in traffic with windows open or with vents set to “outside air.” Do not use solvent-based glues, paints, or degreasers in poorly ventilated areas. When doing home repairs, ventilate well and use air purifiers with activated carbon.
Polycyclic aromatic hydrocarbons (PAHs)PAHs are linked to increased risks of cancer as whole, as well as increased risks of lung, bladder, and breast cancersPAHs are a group of chemicals formed when organic material is burned incompletely, and they are widespread in the environment. One of these PAHs, benzo[a]pyrene is classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans. Several other PAHs are classified as Group 2A (probably carcinogenic) or Group 2B (possibly carcinogenic).8Jameson CW. Polycyclic aromatic hydrocarbons and associated occupational exposures. In: Baan RA, Stewart BW, Straif K, editors. Tumour Site Concordance and Mechanisms of Carcinogenesis. Lyon, FR: International Agency for Research on Cancer; 2019. Chapter 7. Available from: https://www.ncbi.nlm.nih.gov/books/NBK570325/ PAH exposures most commonly occur through breathing contaminated air–including from tobacco smoke–or through diet. Occupational and population studies link PAH exposure through air to increased lung, bladder, and breast cancers, and cancer as a whole.9Huang F, Zhang Y et al. Characterization, sources and excessive cancer risk of pm2.5-bound polycyclic aromatic hydrocarbons in different green spaces in Lin’an, Hangzhou, China. Bulletin of Environmental Contamination and Toxicology. 2021 Sep;107(3):519-529; Rota M, Bosetti C, Boccia S, Boffetta P, La Vecchia C. Occupational exposures to polycyclic aromatic hydrocarbons and respiratory and urinary tract cancers: an updated systematic review and a meta-analysis to 2014. Archives of Toxicology. 2014 Aug;88(8):1479-90; Cumberbatch MG, Cox A, Teare D, Catto JW. Contemporary occupational carcinogen exposure and bladder cancer: a systematic review and meta-analysis. JAMA Oncology. 2015 Dec;1(9):1282-90; Gamboa-Loira B, López-Carrillo L, Mar-Sánchez Y, Stern D, Cebrián ME. Epidemiologic evidence of exposure to polycyclic aromatic hydrocarbons and breast cancer: a systematic review and meta-analysis. Chemosphere. 2022 Mar;290:133237; Wagner M, Bolm-Audorff U et al. Occupational polycyclic aromatic hydrocarbon exposure and risk of larynx cancer: a systematic review and meta-analysis. Occupational and Environmental Medicine. 2015 Mar;72(3):226-33; Paget-Bailly S, Cyr D, Luce D. Occupational exposures to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx: a quantitative literature review. International Archives of Occupational and Environmental Health. 2012 May;85(4):341-51; Singh A, Kamal R et al. PAH exposure-associated lung cancer: an updated meta-analysis. Occupational Medicine (Lond). 2018 May 23;68(4):255-261; Zhang Y, Meliefste K, et al. Expanded PAH analysis of household air pollution in a rural region of China with high lung cancer incidence. Environmental Pollution. 2024 Nov 15;361:124717; Arif I, Adams MD, Johnson MT. A meta-analysis of the carcinogenic effects of particulate matter and polycyclic aromatic hydrocarbons. Environmental Pollution. 2024 Jun 15;351:123941.Ventilate well when using a fireplace–ensure flue and chimney are properly maintained. Use stove hoods or open windows when cooking. Limit time on busy roads and around idling cars. Make sure all gas-burning appliances, such as heaters, stoves, dryers, and water heaters, are well-vented and maintained properly. Avoid smoking and secondhand smoke.
Vinyl chlorideIncreased risk of liver cancerClassified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans.10International Agency for Research on Cancer Monograph Working Group. Vinyl chloride. A review of human carcinogens, volume 97. World Health Organization. 2008. Vinyl chloride increases the risk of various liver cancers, including angiosarcoma, hepatocellular carcinoma, and cholangiocellular carcinoma.11IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Volume 97:1,3-Butadiene, Ethylene Oxide and Vinyl Halides (Vinyl Fluoride, Vinyl Chloride and Vinyl Bromide). World Health Organization. 2008; Edwards D, Voronina A, Attwood K, Grand’Maison A. Association between occupational exposures and sarcoma incidence and mortality: systematic review and meta-analysis. Systematic Reviews. 2021 Aug 13;10(1):231; Boffetta P, Matisane L et al. Meta-analysis of studies of occupational exposure to vinyl chloride in relation to cancer mortality. Scandinavian Journal of Work, Environment & Health. 2003;29(3):220-229; United States Environmental Protection Agency. Draft scope of the risk evaluation for vinyl chloride (Ethene, chloro-). CASRN 75-01-4. 2025 Jan;EPA Document# EPA-740-D-25-001.Vinyl chloride is used in making PVC (polyvinyl chloride) plastic, used widely in construction and in wire coatings, vehicle upholstery, and plastic kitchen wares. When PVC is burned, it can release vinyl chloride and other toxic chemicals. Do not burn plastics. Avoid packaging made with PVC when possible. Well water located near industrial areas should be tested for vinyl chloride. The greatest exposures to vinyl chloride are occupational, in places that produce PVC, plastics, resins, coatings, pipes, and flooring. People who work in these manufacturing plants should follow all OSHA guidelines, use proper personal protective equipment, work in areas with ventilation or fume extraction, and test liver function regularly.
ChemicalLink to CancerScientific Evidence of Link to CancerHow to Minimize Exposure
In food and drink
ArsenicIncreased risk of skin, lung, bladder, and liver cancersClassified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans.12International Agency for Research on Cancer Monograph Working Group. Arsenic, metals, fibres, and dusts. A review of human carcinogens, volume 100C. World Health Organization. 2012. Studies in populations chronically exposed to arsenic-contaminated water show higher cancer rates.13Smith AH, Marshall G et al. Mortality in young adults following in utero and childhood exposure to arsenic in drinking water. Environmental Health Perspectives. 2012; 120(11): 1527–1531. More information and supporting studies can be found on the Collaborative for Health & Environment arsenic information page.Avoid drinking water from private wells that have not been tested for water quality; use water filters certified for arsenic; avoid rice from high-arsenic areas.
Bisphenol APossible link to breast and prostate cancer after early-life exposureEvidence from animal studies and some human studies show hormone-disrupting effects and potential cancer risks.14Khan NG, Correia , et al. A comprehensive review on the carcinogenic potential of bisphenol A: clues and evidence. Environmental Science and Pollution Research International. 2021 Apr;28(16):19643-19663. More information and supporting studies can be found on the Collaborative for Health & Environment bisphenols information page.Use glass or stainless steel food and drink containers rather than plastic; avoid heating food in plastic containers; reduce consumption of canned foods with BPA-lined cans.
DioxinIncreased risks of lymphomas, soft tissue sarcomas, multiple myeloma, and prostate cancer.Classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans.15International Agency for Research on Cancer Monograph Working Group. Polychlorinated Dibenzo-para-dioxins and polychlorinated dibenzofurans. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans Volume 69. World Health Organization. 1997. Studies show dioxin is linked to higher risks of lymphomas, soft tissue sarcomes, multiple myeloma, prostate cancer, and cancers as a whole.16IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. Chemical Agents and Related Occupations, Volume 100 F: A Review of Human Carcinogens. World Health Organization. 2012; Xu J, Ye Y et al. Association between dioxin and cancer incidence and mortality: a meta-analysis. Scientific Reports. 2016 Nov 29;6:38012; Leng L, Chen X, Li CP, Luo XY, Tang NJ. 2,3,7,8-Tetrachlorodibezo-p-dioxin exposure and prostate cancer: a meta-analysis of cohort studies. Public Health. 2014 Mar;128(3):207-13; Steenland K, Bertazzi P, Baccarelli A, Kogevinas M. Dioxin revisited: Developments since the 1997 IARC classification of dioxin as a human carcinogen. Environmental Health Perspectives. 2004;112(13):1265-1268. More information and supporting studies can be found on the Collaborative for Health & Environment dioxin information page.Dioxin accumulates in the food chain, especially in animal fats, so limiting animal fat intake and eating lower on the food chain–vegetables, grains, small fish and animals instead of large animals–reduces dioxin exposure. Follow local advisories for fish and shellfish caught in rivers, lakes, or coastal waters known for contamination.
Endocrine-disrupting chemicalsPossible link to breast and testicular cancers, as well as osteosarcoma and lymphoma among childrenEndocrine-disrupting chemicals (EDCs) are any chemical that interferes with the body’s endocrine (hormone-producing) system. There are thousands of known or suspected EDCs, and some of the more well-studied ones include but are not limited to bisphenols, phthlates, dioxins, and diethylstilbestrol. They can cause many health effects, such as infertility and birth defects, and cancers related to the reproductive system, with links to breast and testicular cancers.17Rocha PRS, Oliviera VD, Vasques CI, Dos Reis PED, Amato AM. Exposure to endocrine disruptors and risk of breast cancer: a systematic review. Critical Reviews in Oncology/Hematology. 2021 May;161:103330; Sifakis S, Androutsopoulos V, Tsatsakis A, Spandidos D. Human exposure to endocrine disrupting chemicals: effects on the male and female reproductive systems. Environmental Toxicology and Pharmacology. 2017;51:56-70. Children exposed to phthlates in medications were found to have increased risks of osteosarcoma and Hodgkin and non-Hodgkin lymphomas.18Ahern TP, Spector LG et al. Medication-associated phthalate exposure and childhood cancer incidence. Journal of the National Cancer Institute. 2022 Feb 18:djac045. More information and supporting studies can be found on the Collaborative for Health & Environment endocrine-disrupting hormones information page.(Refer to entry below for how to avoid EDCs in cosmetics.) Never microwave or heat food in plastic, including plastic packaging labeled “microwave safe.” Limit use of Teflon and other nonstick cookware, and throw away pans that have damaged nonstick surfaces. Use cast iron, stainless steel, glass, and ceramic food containers when possible. Consuming organic produce can reduce exposure to synthetic pesticides, but does not guarantee no exposure to EDCs, so even organic produce should be thoroughly washed. Choose fresh, unpackaged food when possible.
Per- and polyfluoroalkyl substances (PFAS)Linked to increased risks of kidney and testicular cancers, and possibly other cancers such as lung and thyroid.PFAS exposure is linked to kidney and testicular cancers.19Seyyedsalehi M, Boffetta P. Per- and poly-fluorolkyl substances (PFAS) exposure and risk of kidney, liver, and testicular cancers: a systematic review and meta-analysis. La Medicina del Lavoro. 2023;114(5):e2023040. PFAS may possibly be linked to lung, thyroid, prostate and ovarian cancers, and non-Hodgkin lymphoma.20Sassano M, Zhang S, Kappil E et al. Exposure to per- and poly-fluoroalkyl substances and hematological cancer: a systematic review and meta-analysis. Cancer Epidemiology. 2025;97:102831; Sassano M, Seyyedsalehi M et al. Exposure to per- and poly-fluoroalkyl substances and lung, head and neck, and thyroid cancer: A systematic review and meta-analysis. Environmental Research. 2025;266:120606; van Gerwan M, Chung T et al. Per- and polyfluoroalkyl substances (PFAS) exposure and thyroid cancer: systematic review and meta-analysis. Toxicology Letters. 2024;399:52-58; Yang S, Dong H, Gou X, et al. Exposure to per‐ and polyfluoroalkyl substances and the risk of prostate and ovarian cancer: an epidemiologic meta‐analysis. American Journal of Industrial Medicine. 2025;68(5):399-412; Seyyedsalehi M, Kappil E et al. Per- and poly-fluoroalkyl substances (PFAS) exposure and risk of breast, and female genital cancers: a systematic review and meta-analysis. La Medicina del Lavoro. 2024;115(6):e2024043PFAS are used to make grease-, water-, and stain-resistant products. Limit use of grease-resistant food packaging such as fast food wrappers, microwave popcorn bags, and takeout containers. Use unbleached parchment paper instead of nonstick baking sheets. Avoid Teflon pans made before 2014, which may contain a type of PFAS called perfluorooctanoic acid, and throw out nonstick pans that have damaged coatings.
PesticidesThe chemicals used in pesticides can collectively cause a variety of cancers, including most commonly skin, lung, and nasal cancers.Chemicals commonly used in pesticides include maneb, nickel sulfate hexahydrate, hexavalent chromium, creosote, arsenic compounds, permethrin, and organophosphates. These chemicals are either known carcinogens or probable carcinogens which can cause skin, lung, nasal, bladder, liver, and kidney cancers as well as other cancers and diseases. More information and supporting studies can be found on the Collaborative for Health & Environment pesticide information page.Reduce pesticide use at home, and instead practice Integrated Pest Management for home and garden: prevent household pests by removing their sources of food, water, and shelter. Clean up or seal food sources such as food spills in the kitchen, pet foods, garbage. Repair broken windows, doors, or screens. Remove woodpiles from areas near the house. Leave shoes near the door to avoid tracking pesticide into the house.
Polycyclic aromatic hydrocarbons (PAHs)PAHs are linked to increased risks of cancer as whole, as well as increased risks of lung, bladder, and breast cancersPAHs are a group of chemicals formed when organic material is burned incompletely, and they are widespread in the environment. One of these PAHs, benzo[a]pyrene is classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans. Several other PAHs are classified as Group 2A (probably carcinogenic) or Group 2B (possibly carcinogenic).21Jameson CW. Polycyclic aromatic hydrocarbons and associated occupational exposures. In: Baan RA, Stewart BW, Straif K, editors. Tumour Site Concordance and Mechanisms of Carcinogenesis. Lyon, FR: International Agency for Research on Cancer; 2019. Chapter 7. Available from: https://www.ncbi.nlm.nih.gov/books/NBK570325/ PAH exposures most commonly occur through breathing contaminated air–including from tobacco smoke–or through diet. Occupational and population studies link PAH exposure through air to increased lung, bladder, and breast cancers, and cancer as a whole.22Huang F, Zhang Y et al. Characterization, sources and excessive cancer risk of pm2.5-bound polycyclic aromatic hydrocarbons in different green spaces in Lin’an, Hangzhou, China. Bulletin of Environmental Contamination and Toxicology. 2021 Sep;107(3):519-529; Rota M, Bosetti C, Boccia S, Boffetta P, La Vecchia C. Occupational exposures to polycyclic aromatic hydrocarbons and respiratory and urinary tract cancers: an updated systematic review and a meta-analysis to 2014. Archives of Toxicology. 2014 Aug;88(8):1479-90; Cumberbatch MG, Cox A, Teare D, Catto JW. Contemporary occupational carcinogen exposure and bladder cancer: a systematic review and meta-analysis. JAMA Oncology. 2015 Dec;1(9):1282-90; Gamboa-Loira B, López-Carrillo L, Mar-Sánchez Y, Stern D, Cebrián ME. Epidemiologic evidence of exposure to polycyclic aromatic hydrocarbons and breast cancer: a systematic review and meta-analysis. Chemosphere. 2022 Mar;290:133237; Wagner M, Bolm-Audorff U et al. Occupational polycyclic aromatic hydrocarbon exposure and risk of larynx cancer: a systematic review and meta-analysis. Occupational and Environmental Medicine. 2015 Mar;72(3):226-33; Paget-Bailly S, Cyr D, Luce D. Occupational exposures to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx: a quantitative literature review. International Archives of Occupational and Environmental Health. 2012 May;85(4):341-51; Singh A, Kamal R et al. PAH exposure-associated lung cancer: an updated meta-analysis. Occupational Medicine (Lond). 2018 May 23;68(4):255-261; Zhang Y, Meliefste K, et al. Expanded PAH analysis of household air pollution in a rural region of China with high lung cancer incidence. Environmental Pollution. 2024 Nov 15;361:124717; Arif I, Adams MD, Johnson MT. A meta-analysis of the carcinogenic effects of particulate matter and polycyclic aromatic hydrocarbons. Environmental Pollution. 2024 Jun 15;351:123941.Limit consumption of grilled, smoked, and charred foods, and remove blackened parts of cooked food. Avoid cooking at very high temperatures or directly on open flames–if cooking with open flame, broil with the flame above the food so that fat does not drip into the flame and send up smoke that may coat the food in PAHs. In general, it is better to cook food at lower temperatures for longer times.
ChemicalLink to CancerScientific Evidence of Link to CancerHow to Minimize Exposure
Indoors
AsbestosCauses mesothelioma and lung cancer; linked to increased risks of laryngeal, and ovarian cancersClassified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans. There is strong evidence from occupational studies linking asbestos exposure to mesothelioma and lung cancer.23Stayner L, Welch L, Lemen R. The worldwide pandemic of asbestos-related diseases. Annual Review of Public Health. 2013;34:205-216; Bianchi C and Bianchi T. Malignant mesothelioma: global incidence and relationship with asbestos. Industrial Health. 2007;45:379-387; LaDou J. The asbestos cancer epidemic. Environmental Health Perspectives. 2004;112(3):285-290. More information and supporting studies can be found on the Collaborative for Health & Environment asbestos information page.Avoid disturbing asbestos-containing materials in old buildings, and hire professionals for safe removal. Follow local regulations and safety guidelines during home renovations.
FormaldehydeIncreased risks of nasal cancers and myeloid leukemia.Classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans.24IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Volume 88: Formaldehyde, 2-Butoxyethanol and 1-tert-Butoxypropan-2-ol. World Health Organization. 2006. Formaldehyde inhalation is linked to nasopharyngeal and sinonasal cancers, as well as myeloid leukemia.25Torre G, Vitello T, Cocchiara R, Della Rocca C. Relationship between formaldehyde exposure, respiratory irritant effects and cancers: a review of reviews. Public Health. 2023;218:186-196; Environmental Protection Agency. IRIS toxicological review of formaldehyde (inhalation). CASRN 50-00-0. 2024 Aug;EPA/635/R-24/162cF.Off-gas new furniture, rugs, and curtains for several days in a well-ventilated area before use. Use air purifiers with activated carbon filters. Choose home products labeled “low VOCs” (Volatile Organic Compounds) or “formaldehyde-free.” Ensure wood stoves and fireplaces are properly maintained and well-ventilated.
SmokingWell-established cause of lung cancer, and also increases risks of other cancers including larynx, mouth, esophagus, pharynx.Classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans. Seminal studies by Doll and Hill in the 1950s first established strong link between smoking and lung cancer.26Doll R, Hill A. The mortality of doctors in relation to their smoking habits. British Medical Journal. 1954:ii;1451-1455. More information can be found on the American Cancer Society tobacco smoke page.Avoid smoking and secondhand smoke. The US Preventive Services Task Force recommends that smokers and those who have quit within the past 15 years get annual lung cancer screenings.
Wood dustIncreased risks of lung cancer, leukemia, and head, neck, and oral cancers.Classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans.27IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Wood Dust and Formaldehyde. World Health Organization. 1995. There is strong evidence from occupational studies linking wood dust exposure to lung cancer; nasal adenocarcinoma and nasopharyngeal cancer; and leukemia.28Alonso-Sardón M, Chamorro AJ et al. Association between occupational exposure to wood dust and cancer: a systematic review and meta-analysis. PLoS One. 2015 Jul 20;10(7):e0133024; Beigzadeh Z, Pourhassan B, Kalantary S, Golbabaei F. Occupational exposure to wood dust and risk of nasopharyngeal cancer: A systematic review and meta-analysis. Environmental Research. 2019 Apr;171:170-176; E M, Yin J et al. Wood dust exposure and risks of nasopharyngeal carcinoma: a meta-analysis. European Journal of Public Health. 2020 Aug 1;30(4):817-822; Binazzi A, Ferrante P, Marinaccio A. Occupational exposure and sinonasal cancer: a systematic review and meta-analysis. BMC Cancer. 2015 Feb 13;15:49; Hancock DG, Langley ME, Chia KL, Woodman RJ, Shanahan EM. Wood dust exposure and lung cancer risk: a meta-analysis. Occupational and Environmental Medicine. 2015 Dec;72(12):889-98; Curiel-Garcia T, Candal-Pedreira C et al. Wood dust exposure and small cell lung cancer: a systematic review and meta-analysis. Journal of Exposure Science and Environmental Epidemiology. 2024;24:457-464; Soleimani Y, Daraei M et al. Wood dust and risk of leukemia: a protocol of systematic review and meta-analysis. Asian Pacific Journal of Environment and Cancer. 2023;7(1):155-158; Mofidi A, Tompa E et al. Occupational exposure to wood dust and the burden of nasopharynx and sinonasal cancer in Canada. International Journal of Environmental Research and Public Health. 2022; Meng E, Xin Z, Dou J, Yin J. Meta-analysis of the relationship between occupational/environmental exposure to wood dust and laryngeal cancer. Cancer Medicine. 2024;13(20):p.e70330-n/a.Use HEPA filters, air scrubbers, and appropriate respirator masks when woodworking. Work in a well-ventilated area, and work wet when possible by dampening wood before cutting or sanding. Use low-speed tools or hand tools when possible, as these create less wood dust. Change clothes and shower as soon as possible after working with wood.
ChemicalLink to CancerScientific Evidence of Link to CancerHow to Minimize Exposure
Cosmetics
Endocrine-disrupting chemicalsPossible link to breast and testicular cancers, as well as osteosarcoma and lymphoma among childrenEndocrine-disrupting chemicals (EDCs) are any chemical that interferes with the body’s endocrine (hormone-producing) system. There are thousands of known or suspected EDCs, and some of the more well-studied ones include but are not limited to bisphenols, phthlates, dioxins, and diethylstilbestrol. They can cause many health effects, such as infertility and birth defects, and cancers related to the reproductive system, with links to breast and testicular cancers.29Rocha PRS, Oliviera VD, Vasques CI, Dos Reis PED, Amato AM. Exposure to endocrine disruptors and risk of breast cancer: a systematic review. Critical Reviews in Oncology/Hematology. 2021 May;161:103330; Sifakis S, Androutsopoulos V, Tsatsakis A, Spandidos D. Human exposure to endocrine disrupting chemicals: effects on the male and female reproductive systems. Environmental Toxicology and Pharmacology. 2017;51:56-70. Children exposed to phthlates in medications were found to have increased risks of osteosarcoma and Hodgkin and non-Hodgkin lymphomas.30Ahern TP, Spector LG et al. Medication-associated phthalate exposure and childhood cancer incidence. Journal of the National Cancer Institute. 2022 Feb 18:djac045. More information and supporting studies can be found on the Collaborative for Health & Environment endocrine-disrupting hormones information page.Some common suspected EDCs found in cosmetics include phthalates (used in synthetic fragrances), parabens (used as preservative), and triclosan (used in antibacterial personal products). Read labels and avoid using products with these ingredients. Sometimes phthlates are not explicitly listed as ingredients, so avoid added fragrances when possible.
Polycyclic aromatic hydrocarbons (PAHs)PAHs are linked to increased risks of cancer as whole, as well as increased risks of lung, bladder, and breast cancersPAHs are a group of chemicals formed when organic material is burned incompletely, and they are widespread in the environment. One of these PAHs, benzo[a]pyrene is classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans. Several other PAHs are classified as Group 2A (probably carcinogenic) or Group 2B (possibly carcinogenic).31Jameson CW. Polycyclic aromatic hydrocarbons and associated occupational exposures. In: Baan RA, Stewart BW, Straif K, editors. Tumour Site Concordance and Mechanisms of Carcinogenesis. Lyon, FR: International Agency for Research on Cancer; 2019. Chapter 7. Available from: https://www.ncbi.nlm.nih.gov/books/NBK570325/ PAH exposures most commonly occur through breathing contaminated air–including from tobacco smoke–or through diet. Occupational and population studies link PAH exposure through air to increased lung, bladder, and breast cancers, and cancer as a whole.32Huang F, Zhang Y et al. Characterization, sources and excessive cancer risk of pm2.5-bound polycyclic aromatic hydrocarbons in different green spaces in Lin’an, Hangzhou, China. Bulletin of Environmental Contamination and Toxicology. 2021 Sep;107(3):519-529; Rota M, Bosetti C, Boccia S, Boffetta P, La Vecchia C. Occupational exposures to polycyclic aromatic hydrocarbons and respiratory and urinary tract cancers: an updated systematic review and a meta-analysis to 2014. Archives of Toxicology. 2014 Aug;88(8):1479-90; Cumberbatch MG, Cox A, Teare D, Catto JW. Contemporary occupational carcinogen exposure and bladder cancer: a systematic review and meta-analysis. JAMA Oncology. 2015 Dec;1(9):1282-90; Gamboa-Loira B, López-Carrillo L, Mar-Sánchez Y, Stern D, Cebrián ME. Epidemiologic evidence of exposure to polycyclic aromatic hydrocarbons and breast cancer: a systematic review and meta-analysis. Chemosphere. 2022 Mar;290:133237; Wagner M, Bolm-Audorff U et al. Occupational polycyclic aromatic hydrocarbon exposure and risk of larynx cancer: a systematic review and meta-analysis. Occupational and Environmental Medicine. 2015 Mar;72(3):226-33; Paget-Bailly S, Cyr D, Luce D. Occupational exposures to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx: a quantitative literature review. International Archives of Occupational and Environmental Health. 2012 May;85(4):341-51; Singh A, Kamal R et al. PAH exposure-associated lung cancer: an updated meta-analysis. Occupational Medicine (Lond). 2018 May 23;68(4):255-261; Zhang Y, Meliefste K, et al. Expanded PAH analysis of household air pollution in a rural region of China with high lung cancer incidence. Environmental Pollution. 2024 Nov 15;361:124717; Arif I, Adams MD, Johnson MT. A meta-analysis of the carcinogenic effects of particulate matter and polycyclic aromatic hydrocarbons. Environmental Pollution. 2024 Jun 15;351:123941.PAHs are usually contaminants and not ingredients in cosmetics; they can be found in petroleum-derived products (such as lip balms and petroleum jelly) or black-colored products (such as eyeliner and mascara). Avoid products using coal tar, and look for pharmaceutical-grade/highly refined mineral oils and petroleum-based products.
Viruses and bacteriaInfections with specific viruses and bacteria can cause cancers including liver, cervical, stomach, head and neck, lymphoma, skin and colorectal.Infections with specific viruses—including hepatitis B and C, high-risk strains of HPV, and Epstein-Barr virus (EBV)—are established causes of cancers such as liver, cervical, stomach, head and neck, lymphoma, and skin. Likewise, the bacterium Helicobacter pylori is a well-established contributor to stomach cancer and may cause colorectal cancer. Other bacteria are also linked to various cancers; for example, Streptococcus bovis is regularly associated with colorectal cancers.33The American Cancer Society medical and editorial content team. Viruses that can lead to cancer. American Cancer Society. March 31, 2022. Viewed April 11, 2022; Blackburn K, Jones V. 8 viruses that cause cancer. MD Anderson Cancer Center. March 2025. Viewed July 20, 2025; Ford AC, Yuan Y, Moayyedi P. Helicobacter pylori eradication therapy to prevent gastric cancer: systematic review and meta-analysis. Gut. 2020 Dec;69(12):2113-2121; Zuo Y, Jing Z, Bie M, et al. Association between Helicobacter pylori infection and the risk of colorectal cancer: A systematic review and meta-analysis. Medicine (Baltimore). 2020 Sep 11;99(37):e21832; Krishnan S, Eslick G. Streptococcus bovis infection and colorectal neoplasia: a meta-analysis. Colorectal Disease. 2014 Sep; 16(9):672-680; Tavakoli A, Monavari SH et al. Association between Epstein-Barr virus infection and gastric cancer: a systematic review and meta-analysis. BMC Cancer. 2020 Jun 1;20(1):493; Tan R, Zhu X, Sun Y, et al. The association of HBV infection and head and neck cancer: a systematic review and meta-analysis. BMC Cancer. 2024 Feb 16;24:225; Wang H, Chen X, Liu K, et al. Associations between gastric cancer risk and virus infection other than Epstein-Barr virus: a systematic review and meta-analysis based on epidemiological studies. Clinical and Translational Gastroenterology. 2020;11(7):e00201.Some cancer-causing viruses can be vaccinated against, such as HPV and hepatitis B. Screen for H. pylori. Practice safe sex, ensure clean needle use, treat infections early. Support immune health through nutrition, sleep, and stress reduction.
Electromagnetic fieldsEvidence is conflicting and inconclusive on whether electromagnetic fields have any effect on health, including cancers.Researchers have studied whether EMFs are linked to various cancers, including brain cancers such as glioma and meningioma in adults and in children. They have found conflicting evidence, so at the moment, EMFs cannot be conclusively classified as a carcinogen.34Karipidis K, Baaken D et al. The effect of exposure to radiofrequency fields on cancer risk in the general and working population: a systematic review of human observational studies—Part I: most researched outcomes. Environment International. 2024 Sep;191:108983; IARC Monographs on the Identification of Carcinogenic Hazards to Humans. International Agency for Research on Cancer. Viewed April 8, 2023; Lewczuk B, Redlarski G et al. Influence of electric, magnetic, and electromagnetic fields on the circadian system: current stage of knowledge. BioMed Research International. 2014;2014:169459; Akerstedt T, Arnetz B, Ficca G, Paulsson LE, Kallner A. A 50-Hz electromagnetic field impairs sleep. Journal of Sleep Research. 1999 Mar;8(1):77-81; Morales-Suarez-Varela. Relationship between parental exposure to radiofrequency electromagnetic fields and primarily hematopoietic neoplasms (lymphoma, leukemia) and tumors in the central nervous system in children: a systematic review. Reviews on Environmental Health. 2024;39(3):499-510.All electrical devices and appliances give off EMFs. Though there is currently no scientific evidence that reducing EMF exposure will reduce cancer risks, if you would like to reduce exposure as a precaution, you can limit use of electrical devices such as cell phones, computers, microwaves, etc. For example, you can turn off devices when they’re not being used, keep devices away from your body, and reduce the time you use your cell phone and other devices.
Ionizing radiationIncreased risks of various cancers including skin, brain, bladder, breast, colorectal, kidney, and lung.Classified as a Group 1 carcinogen by IARC, meaning there is sufficient evidence that this chemical causes cancer in humans.35El Ghissassi F, Baan R et al. WHO International Agency for Research on Cancer Monograph Working Group. A review of human carcinogens—part D: radiation. Lancet Oncology. 2009 Aug;10(8):751-2. Some common exposures to ionizing radiation occur through sun exposure; radon, which emanates naturally from rocks and soil; and through X-rays, CT scans, and nuclear medicine scans as part of medical procedures. People who have higher exposures to the sun or to indoor tanning have increased risk of skin cancers.36El Ghissassi F, Baan R et al. WHO International Agency for Research on Cancer Monograph Working Group. A review of human carcinogens—part D: radiation. Lancet Oncology. 2009 Aug;10(8):751-2; Colantonio S, Bracken MB, Beecker J. The association of indoor tanning and melanoma in adults: systematic review and meta-analysis. Journal of the American Academy of Dermatology. 2014 May;70(5):847-57.e1-18; Wehner MR, Shive ML et al. Indoor tanning and non-melanoma skin cancer: systematic review and meta-analysis. BMJ. 2012 Oct 2;345:e5909; O’Sullivan DE, Brenner DR et al; ComPARe Study Group. Indoor tanning and skin cancer in Canada: a meta-analysis and attributable burden estimation. Cancer Epidemiology. 2019 Apr;59:1-7; Boniol M, Autier P, Boyle P, Gandini S. Cutaneous melanoma attributable to sunbed use: systematic review and meta-analysis. BMJ. 2012 Jul 24;345:e4757. People who are exposed to radiation from repeated doses of medical imaging and treatment (including x-rays) are also at increased risk of various cancers, including brain, bladder, breast, colorectal, kidney, and lung.37Wallis CJ, Mahar AL et al. Second malignancies after radiotherapy for prostate cancer: systematic review and meta-analysis. British Medical Journal. 2016 Mar 2;352:i851; Rombouts AJM, Hugen N et al. Does pelvic radiation increase rectal cancer incidence?—a systematic review and meta-analysis. Cancer Treatment Reviews. 2018 Jul;68:136-144; Grantzau T, Overgaard J. Risk of second non-breast cancer after radiotherapy for breast cancer: a systematic review and meta-analysis of 762,468 patients. Radiotherapy and Oncology. 2015 Jan;114(1):56-65; Grantzau T, Overgaard J. Risk of second non-breast cancer among patients treated with and without postoperative radiotherapy for primary breast cancer: a systematic review and meta-analysis of population-based studies including 522,739 patients. Radiotherapy and Oncology. 2016 Dec;121(3):402-413; Zhu Z, Zhao S et al. Risk of secondary rectal cancer and colon cancer after radiotherapy for prostate cancer: a meta-analysis. International Journal of Colorectal Disease. 2018 Sep;33(9):1149-1158; Doi K, Mieno MN, Shimada Y, Yonehara H, Yoshinaga S. Meta-analysis of second cancer risk after radiotherapy among childhood cancer survivors. Radiation Protection Dosimetry. 2011 Jul;146(1-3):263-7; Wu Y, Chong Y et al. Second primary malignancies associated with radiation therapy in cervical cancer patients diagnosed between 1975 and 2011: a population-based competing-risk study. Annals of Translational Medicine. 2021 Sep;9(17):1375; Rombouts AJM, Hugen N et al. Increased risk for second primary rectal cancer after pelvic radiation therapy. European Journal of Cancer. 2020 Jan;124:142-151; Mazonakis M, Kachris S, Damilakis J. Second cancer risk from radiation therapy for common solid tumors diagnosed in reproductive-aged females. Radiation Protection Dosimetry. 2018 Dec 1;182(2):208-214; Abalo KD, Rage E et al. Early life ionizing radiation exposure and cancer risks: systematic review and meta-analysis. Pediatric Radiology. 2021 Jan;51(1):45-56; Memon A, Rogers I, Paudyal P, Sundin J. Dental x-rays and the risk of thyroid cancer and meningioma: a systematic review and meta-analysis of current epidemiological evidence. Thyroid. 2019 Nov;29(11):1572-1593.Ionizing radiation is energy released by atoms, either as high-energy electromagnetic waves (like X-rays) or as energetic particles. This type of radiation has enough energy to remove electrons from atoms, which can damage biological tissue but also has many beneficial uses, including in medicine and agriculture. To minimize cancer risks, opt for non-ionizing alternatives–such as MRIs and ultrasounds–when clinically appropriate. In cancer treatments, radiotherapy is sometimes necessary; this therapy will be precisely targeted and carefully dosed, but may still have side effects such as fatigue and, in rare cases, later secondary cancers. Schedule regular follow-up appointments with your oncologist to monitor for later effects.

*IARC is the acronym for the International Agency for Research on Cancer. It is the specialized cancer agency of the World Health Organization, and its mission is cancer research for cancer prevention.

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