Cancer and the Environment

Cancer is a disease with many risk factors; those factors can affect the illness in ways that are not fully understood. Most cancers take a long time to develop. Studies have shown that depending on the type of cancer, some cancers may take as long as 40 years to develop after exposure to some substances.

Through surveillance and tracking, scientists have observed a relationship between some cancers and the presence of certain environmental pollutants. This relationship does not rule out other causes but does suggest that there are factors in the environment that may increase the risk for some cancers. The cause of many cancer types is unknown and likely determined by many factors operating at different points in the lifespan.

Major risk factors for cancer include tobacco use, obesity, physical inactivity, and sun exposure. Genetic factors also seem to play a role in some types of cancer. Exposure to ionizing radiation may also be a risk factor in some instances. Several chemical exposures have been found to be associated with a higher risk of cancer.

Although environmental pollution has been a source of great public concern for decades, more research is needed about environmental exposures at the community level. Evidence is building to support a link between cancer and lower levels of exposures to environmental pollutants.