Causes of Breast Cancer: Environmental Factors

Patterns in the incidence of breast cancer indicate that it’s not just hereditary and that some routine environmental exposures as well as lifestyle may play a major role. This makes prevention a realistic goal in many cases. Based on large studies of twin, researchers estimate that factors other than inherited gens are involved in the vast majority of breast cancers.

Laboratory research shows that chemicals may contribute to breast cancer risk by damaging DNA, promoting tumor growth, or increasing susceptibility by altering how the mammary glands develop. Chemicals identified as causing breast cancer in animals or disrupting hormone systems are commonly found in people’s bodies and in the environment, including in homes.

Chemicals that have a suspected link to breast cancer:

Strong Link:

Smoking and Environmental Tobacco Smoke- whether you smoke yourself or exposed to passive smoking -combination of smoke emitted from the burning end of a cigarette, cigar, or pipe, and smoke exhaled by the smoker.

Radiation- Radiation therapy to the chest for the treatment of cancers increases the risk of breast cancer. The risk of developing breast cancer depends on the dose of radiation and the age at which it is given. The risk is highest if radiation treatment was used during puberty.

Alcohol- Drinking alcohol increases the risk of breast cancer. The level of risk rises as the amount of alcohol consumed rises.

Suspected Link:

Endocrine Disruptors- A number of natural and synthetic chemicals capable of mimicking the body’s natural hormones. People absorb and store them in small amounts for a long time in our daily life as in drinking water, plastic [Bisphenol-A (BPA)] used for water bottles, baby bottles, and liner for canned food products, pesticides, detergents and cosmetics. These chemicals are related to infertility and cancer.

Polycyclic aromatic hydrocarbon (PAHs)- Air pollution caused by cars, trucks, power plants and tobacco smoke.

Dioxin- They are usually created unintentionally as byproducts of industrial processes, such as the production of pesticides and paper products. Dioxins can even be created as a result of a forest fire. Dioxins enter the human body, through food, air or water. We are mostly exposed to dioxin from consuming meat, fish and milk because it accumulates in fats. It leads to extremely health hazards.

Non-ionizing Radiation- As microwaves and cell phones.

Your risk of getting cancer from a chemical depends on a number of factors, including:

  • The kind of chemical you were exposed to
  • How much of chemical you were in contact with
  • How long the contact lasted
  • How often you were exposed
  • The interaction between the chemical and your genes
  • Your general health

Sources: President's Cancer Panel, 2010; Silent Spring Institute, 2012; U.S. Department of Health and Human Services, Report on Carcinogens, 12th edition, 2011.