How we came to study the environment and its contribution to breast cancer

While many people believe that breast cancer is caused by the genetic makeup we inherit from our parents, researchers have long suspected that cancer is caused by many factors operating at once. In 1964, the World Health Organization stated that:

“The potential scope of cancer prevention is limited by the proportion of human cancers in which extrinsic factors are responsible. These [factors] include all environmental carcinogens (whether identified or not) as well as ‘modifying factors’ that favour neoplasia of apparently intrinsic origin (e.g., hormonal imbalances, dietary deficiencies and metabolic defects). The categories of cncer that are thus influenced, directly or indirectly, by extrinsic factors include many tumours of the skin and mouth, the respiratory, gastrointestinal and urinary tracts, hormone dependent organs (such as the breast, thyroid and uterus), haematopoietic and lymphopoietic systems, which, collectively account for more than three-quarters of human cancers. It would seem, therefore, that the majority of human cancer is potentially preventable.”

Two British researchers, Sir Richard Doll and Sir Richard Peto, in 1981 also concluded that “Genetic factors and age also affect cancer onset rates, of course, but this does not affect the conclusion that much human cancer is avoidable.”

While we cannot change our genes, we have some control over the environment to which we are exposed. Based on this premise, the National Institute of Environmental Health Sciences (NIEHS) and the National Cancer Institute (NCI) commissioned a national study on environmental health risks in breast cancer in 2003. The focus of this study was to examine the impact of prepubertal exposures that may affect pubertal development and predispose a woman to breast cancer.

In 2010, to complement the on-going study of puberty, NIEHS and NCI established the Breast Cancer and the Environment Research Program (BCERP) to expand research into the role of “windows” of exposure that may be important for breast cancer. A hallmark of these studies is the inclusion of the breast cancer community, including breast cancer advocates and community partners. At this time, researchers at the UW-Madison together with their community partners were awarded a five year grant and joined eight other national research groups to study how exposures to chemicals in our environment may contribute to a woman's risk of developing breast cancer.

The Wisconsin Partners include scientists, advocates, and communication educators who are studying how the genes we have inherited may interact with chemical agents in the environment. There is specific focus on key times (“windows”) of high growth and development in young girls.


Advocates working across the state in Milwaukee, Madison, and Door County have joined the effort to bring the concerns of the public to the scientists. The scientists, in turn, work to make public their research findings so that women can have the most up-to-date information to lessen their risks of developing breast cancer, both for themselves and their daughters.

Please join us! We will continue to publish the latest information from the national and state studies as they become available. This site contains more information on the team of researchers, what we know so far, what you can do to protect yourself and your daughters, and where to go for more information.