Breast Cancer and the Environment - a new report on Prevention

It’s Breast Cancer Awareness month. It seems everywhere I turn, there is a pink reminder of the disease that is the leading cause of death for women on the late 30s to early 50s.

With one in eight women diagnosed at some point in their lifetime, most everyone knows someone who has been diagnosed with this disease and doesn’t need to be reminded of the devastation this diagnosis leaves in its path.

Most of us already know about breast cancer and the importance of early detection, but what we are at a loss for is how to prevent this disease from happening in the first place.

Most breast cancer is not linked to a genetic cause, which suggests that environmental links are important. Lifetime estrogen exposure is a risk factor for the disease - so entering puberty early, delaying childbirth and going through menopause “late” are all risk factors. Women no longer routinely take hormone replacement therapy when they enter menopause and breast cancer rates have fallen – we have eliminated one risk factor. But that doesn’t explain the rising incidence of pre-menopausal breast cancers and it certainly doesn’t explain the cause of all breast cancers.

What about environmental chemicals that mimic estrogen, shouldn’t they be avoided too? What about other chemicals? What do we know about their links to breast cancer? The answer is that we really don’t know, because most chemicals have never been tested for the toxic effects, including breast cancer. In fact, even the relatively few chemicals that do undergone safety testing, are not routinely examined for their impacts on breast tissue.

Now there exists a way for our government to address this problem. The University of California, Berkeley School of Public Health and the Natural Resources Defense Council (NRDC) are pleased to present a new report, Pathways to Breast Cancer: A Case Study for Innovation in Chemical Safety Evaluation. The report is the product of the Breast Cancer and Chemicals Policy project, funded by the California Breast Cancer Research Program. An expert panel of 20 scientists and policy experts investigated the biological mechanisms associated with breast cancer and developed a testing strategy for screening and identifying chemicals that could increase the risk of the disease. I was a co-director of this project and have blogged before about the genesis of the report and our methodology.

Known and Possible Risk Factors for Breast Cancer

Some known or possible risk factors for breast cancer have been identified. They include:

Being a woman
Getting older
Family history of breast cancer
Benign breast problems
Early exposure to ionizing radiation