We Won't Identify Breast Cancer Risks from Chemicals Until We Test for Them

Here we are at the end of October, with another Breast Cancer Awareness month coming to a close. As a breast cancer survivor, I welcome attention being brought to the disease.

But even as pink ribbons proliferate on ad campaigns, bumper stickers, and supermarket shelves, there is somewhere else in need of more breast cancer awareness: the laboratory.

Most of the 80,000 chemicals in circulation since World War II have not been tested for toxic impacts on humans. Yet even for the small portion that does get tested—including pharmaceuticals and pesticides—current protocols don’t call for examining what chemicals do to mammary glands.

Scientists examine cardiac birth defects, developmental delays, and cancer in the thyroid, liver, prostate, ovaries, and other major organs. But common procedures do not put mammary glands on the list of chemical testing end points.

Remember that only a fraction of breast cancer diagnoses can be attributed to genetic mutations. That means lifestyle choices—such as delaying child birth—are part of the equation, but so are environmental risk factors.

Breast cancer is a hormone sensitive disease, so something has to be triggering the disruptions in our endocrine systems. Toxic chemicals are a possible culprit, but we won’t know until we test them specifically for their links to mammary tumors.

A review done by the organization Silent Spring looked at the chemicals that have been studied intensively by the national and international authorities. They identified 216 chemicals that cause mammary tumors in animals, but only three are regulated based on danger to mammary glands—a sign that risks to breast tissue is not a high priority.

Considering that 1 in 8 women will be diagnosed with the disease in their lifetime, and that breast cancer is the leading cause of death among women in their late 30s to early 50s, this has to change.

Mammary glands must become a routine part of chemical testing, and I am proud to say that two of my NRDC colleagues are helping make this happen. Dr. Gina Solomon and Dr. Sarah Janssen have proposed a toxicity testing strategy that can prioritize and test chemicals for their links to breast cancer.

Gina and Sarah’s work comes out of a partnership between NRDC and the University of California, Berkley School of Public Health. Together with a group of 20 medical and policy experts, they released a new report called Pathways to Breast Cancer: A Case Study for Innovation in Chemical Safety Evaluation.

The report recommends that mammary tissue be routinely included in toxicity testing of any chemical. But it goes one step farther. Rather than waiting for a tumor develop, the report calls for identifying and testing for early indicators of disease. If a chemical is shown to mimic estrogen, for example, it could be considered an “upstream” indicator for increasing the risk of breast cancer.

This is groundbreaking work, but it is also timely. Since most chemical companies are multinational, an international body of experts is trying to create a streamlined testing protocol so that all companies are following similar steps.

Gina, Sarah, and their colleagues see this as an opportunity to finally get indicators of breast cancer risk included on the list of key things to examine during chemical testing.

This is the start of us getting answers about which hazardous chemicals we need to regulate and protect ourselves and our daughters from. It is the beginning of true breast cancer awareness.