Definition of Carcinogen and Information

Carcinogen substance is a substance that can cause cancer.

The most common carcinogen is cigarette smoke, which is implicated in nearly all types of cancer and most specifically lung cancerbreast cancerprostate cancer, pharyngeal cancer, stomach cancer, and colorectal cancer.

Other significant carcinogens include

  • Radon, a naturally occurring gas that results from the deterioration of naturally occurring uranium ubiquitously present in rocks and soil
  • Radiation, such as from overexposure to sunlight (ultraviolet) or ionizing radiation such as X-RAY and gamma-ray
  • Industrial chemicals such as benzene, vinyl chloride, and arsenic
  • Pharmaceutical agents such as hormones (oral contraceptives, estrogen supplements)

Some substances are beneficial in small amounts and carcinogenic in large amounts or in cumulative exposure over time, such as sunlight. Certain medications, notably immunosuppressive medications and estrogen-containing drugs, may cause cancer. Others are hazardous at nearly any exposure level.

Chemotherapy drugs, which effectively treat and cure many types of cancer, are themselves carcinogenic for certain types of leukemia and lymphomaradiation therapy as well increases the risk for subsequent cancers, depending on the site of irradiation. Pathogens such as viruses and bacteria cause certain kinds of cancer.

Limiting exposure to carcinogens reduces the likelihood that they will have adverse health effects. In the United States, federal and state regulations provide guidelines for occupational exposure to carcinogens. Other public health measures attempt to reduce carcinogen exposure through educational efforts.

Cancer Causing Substances

COMMON CARCINOGENS
aflatoxins arsenic
asbestos benzene
beryllium cadmium
chromium cigarette smoke
cyclosporine diethylstilbestrol (DES)
epstein-barr virus estrogens
ethylene oxide formaldehyde
helicobacter pylori hepatitis b virus
human papillomavirus (hpv) iodine-131
ionizing radiation methyl chloride
radon sunlight
tobacco vinyl chloride

See also ASBESTOSISBERYLLIOSISCANCER PREVENTIONCANCER RISK FACTORS; ENVIRONMENTAL CIGARETTE SMOKEENVIRONMENTAL HAZARD EXPOSURELIFESTYLE AND CANCER; OCCUPATIONAL HEALTH AND SAFETY; PATHOGEN; RADON EXPOSURE; SMOKING AND CANCER.

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