What are carcinogens?

 
Carcinogens are substances that can cause or increase the risk of developing cancer. Below are a few examples of well-known carcinogens:
  • Smoking
    • In addition to lung cancer, tobacco consumption causes cancer of the larynx, pancreas, kidney, bladder in addition to other cancers.
    • Smoking in conjunction with alcohol drinking leads to a higher risk of cancer of the oral cavity and the esophagus.
    • In most developed countries, tobacco accounts for as much as 30% of all malignant tumors.
  • Heavy alcohol drinking
    • Drinking too much alcohol consistently over a long period of time can cause cancer of the oral cavity, pharynx, larynx, esophagus, and liver, and may increase the risk of breast and colorectal cancers.
  • Pollution
    • Environmental factors such as pollution of air, water or soil is estimated to account for 1-4% of cancers.
    • Indoor carcinogens include tobacco smoke.
    • High levels of arsenic and chlorination byproducts in some countries reach dangerous levels that may be associated with cancer.
  • Chronic infections
    • Hepatitis B infection is associated with liver cancer.
    • The human papillomavirus (HPV) is associated with cancer of the cervix and uterus.
  • Radiation
    • Exposure to high-levels of radiation alters cell activity, which can lead to cancer.
    • Sunlight contains ultraviolet (UV) radiation, which can lead to skin cancer if people are exposed to it too much, especially if it causes bad sunburns.