The importance of occupational origin for a number of cancers, including mesothelioma, sinonasal, lung, nasopharynx, breast, non-melanoma skin cancer, bladder, esophagus, soft tissue sarcoma and stomach, has been highlighted in high-income countries. The carcinogens involved are asbestos, mineral oils, silica, diesel engine exhaust, coal tars and pitches, dioxins, environmental tobacco smoke, radon, tetrachloroethylene, arsenic and strong inorganic mists, and occupational exposures, including shift work, painting or welding. An emerging problem that needs to be addressed is that high-risk professions are now commonly exported to low-income countries.
Obesity is a risk factor for breast (post-menopausal), colorectal, endometrial, kidney, esophageal and pancreatic cancers, though the burden of such diseases explained by diet, weight, and body fat is still uncertain. Alcohol use is clearly associated with liver, aero-digestive tract, breast and colorectal cancers. Dietary recommendations on dietary cancer prevention have been issued by the World Cancer Research Fund.
OTHER RISK FACTORS
Other known risk factors include reproductive factors, environmental pollutants, and ultraviolet (UV) exposure. The extent of exposure to environmental carcinogenic pollutants is unknown, particularly in low-income countries, though the burden adds up to several hundred thousand newly diagnosed cancers per year just for arsenic, air pollution, aflatoxin, polychlorinated biphenyls, and asbestos. Another environmental factor that is not man-made but is an important and preventable risk factor for skin cancer is excessive exposure to UV radiation, primarily from the sun, but also as a result of indoor tanning.